Ok,
**All references to "Right" and "Left" are when sitting on bike**
8/10/13:
So the cam chain tensioner had a slight drip since I bought the bike.
Today I decided to swap the camchain tensioner gasket. I did so and put the chain tensioner back in. Typically I am super cautious but not today, like an idiot, I didnt head GSJacks advice in my own thread:
http://gstwins.com/gsboard/index.php?topic=65092.msg777778#msg777778
So heres what happened. The cam chain tensioner actually locked compressed when I tightened it down. So when I installed it I thought it released and it did not (headphones while working can have a downside). Instead of pulling the valve cover to verify all was good,I cranked for a split second and it sounded weird I STOPPED immediately. This was not even a full crank.
I then pulled the valve cover and removed the right side cover to check timing. While turning it by hand to line up the timing marks I heard a pop and the chain went slack. I stopped..
I then pulled the carbs and air box and removed the tensioner in the long shot hopes that its spring had broken and caused the slack.. no it was still compressed and never released..so here I am. I never even knew they would locked compressed.
What is the next step?????
I have not been into a bike motor past this point so please give me some insight while I go weep in a corner. I am really really pissed at myself.. I am wondering what damage may have been done or not done since I was cranking by hand.
Any advice you give will be great.
I am going to order the manual now from the link.
1998 GS500 just rolled 8800 miles. MINT condition in all respects until today.
**
8/11/13:
Ok valve cover off starting to remove cams:
(http://i1002.photobucket.com/albums/af147/Snake2715/IMAG1825_zpsdd761136.jpg)
So I pulled the carbs and see the intake valves they are there like they always were. I pulled the plugs and left side piston is down and I cant see that valve (got a light in the hole) and there is no valve laying in there. The right side plug the piston is up and I can see the valve there but not sure its broken.
Ok got the cams out and bagged. Pulled the exhaust off and both valves are there...
All buckets and shims spin freely. No valve shims are forced upward or out of their spot now that cams are out.
So the right piston is almost top dead center.. Out to check all valves.. the cams are out so the valves should all be seated correctly I figure..
Intakes look good ( a little sludged up, but thats been there when I bought it). The right valve is seated and looks good..
I check the left valve and its not seated.. its almost seated but there is a small gap..
I check again and I see the crack in the left valve guide..
THIS IS THE LEFT EXHAUST VALVE
(http://i1002.photobucket.com/albums/af147/Snake2715/IMAG1830_zps057f4fab.jpg)
(http://i1002.photobucket.com/albums/af147/Snake2715/IMAG1827_zpsc3af576a.jpg)
From looking down the spark plug hole I see literally no marks on the piston at all. I cant see the whole piston but I see no marks on what I can see.
Interesting enough the left exahust valve was the only one I had to adjust when doing my valve adjustment.. :
http://gstwins.com/gsboard/index.php?topic=63467.msg752485#msg752485
So my questions to this point:
8/21/13:
Head is off. Pic heavy. The left exhaust valve (whle on bike) is not seated as you can see the light shining through in the one pic. I took a few pictures and will post them all.
Notice the guide pin if thats the name is in the right side of the head for reference
(http://i1002.photobucket.com/albums/af147/Snake2715/IMAG1851_zpsce51afdd.jpg)
(http://i1002.photobucket.com/albums/af147/Snake2715/IMAG1852_zps4310d13f.jpg)
(http://i1002.photobucket.com/albums/af147/Snake2715/IMAG1853_zps10964d43.jpg)
Left exhaust valve:
(http://i1002.photobucket.com/albums/af147/Snake2715/IMAG1854_zps3ff135f4.jpg)
Right exhaust valve:
(http://i1002.photobucket.com/albums/af147/Snake2715/IMAG1855_zpsbb41f5c5.jpg)
Right Piston:
(http://i1002.photobucket.com/albums/af147/Snake2715/IMAG1856_zps436d3e4a.jpg)
(http://i1002.photobucket.com/albums/af147/Snake2715/IMAG1858_zps828da557.jpg)
Left Piston. I see no marks on this at all:
(http://i1002.photobucket.com/albums/af147/Snake2715/IMAG1857_zpsd52ddb86.jpg)
Right piston is the raised piston:
(http://i1002.photobucket.com/albums/af147/Snake2715/IMAG1859_zps2f9eb916.jpg)
(http://i1002.photobucket.com/albums/af147/Snake2715/IMAG1860_zps71eda183.jpg)
(http://i1002.photobucket.com/albums/af147/Snake2715/IMAG1861_zps2361e92a.jpg)
(http://i1002.photobucket.com/albums/af147/Snake2715/IMAG1862_zps5c7d7570.jpg)
(http://i1002.photobucket.com/albums/af147/Snake2715/IMAG1863_zps7f1c1891.jpg)
(http://i1002.photobucket.com/albums/af147/Snake2715/IMAG1863_zps7f1c1891.jpg)
(http://i1002.photobucket.com/albums/af147/Snake2715/IMAG1864_zps92fa0f61.jpg)
(http://i1002.photobucket.com/albums/af147/Snake2715/IMAG1862_zps5c7d7570.jpg)
What next?
Your about to learn how to remove cams and cyl head.....take your time.
I will do research as much as possible timing sucks we are about to move.
will I need a shop to do any head work?
New head gasket I presume...
If you are about to move, best wait till you can get to it. if you did break a valve, who knows what other damage is there. untill the head is removed you dont have another direction other then swap out another running engine or scrap the bike. worry about getting settled in a new place, setup your work area, then work on the bike. pull the head and we can go from there. make sure you have a decent camera for some of the step by step stuff, its good reference for reassembly and you can post the pics of your progress for those that can attempt to answer any questions that come up.
Ok well I have 30-45 days to move so I will tear into it soon.
It does not sound to me like you broke a valve. Did you actually see a broken valve? Cause I have a hard time believing you could brake a valve turning it by hand.
So all you did was remove the valve cover and then the cam chain tensioner and put it back in?
Sounds more like the chain was not on properly on the bottom and just felt tight, then when turning over it fell off and is now slack. Thats the best case scenario though.
+1
My thoughts exactly after reading Snake's post late last night and thought I'd wait till morning and I was awake before replying. :icon_lol: Did you actually see a broken valve Snake? When I broke off an exhaust valve while cranking to start on a freezing cold morning the engine stopped with a big bang. Removing the right cover and turning the crank with a wrench it would only go a bit in either direction before locking up. Removed the plugs and peeked in and saw the broken valve in there. If you haven't actually seen a broke valve you can investigate further before pulling the head.
I don't see a broken valve.. how do i investigate?
so I pulled the carbs and see the valves they are there like they always were. I pulled the plugs and left side piston is down and I cant see that valve (got a light in the hole) and there is no valve laying in there. The right side plug the piston is up and I can see the valve there but not sure its broken.
How can I check this? I know the timing is off how do I get that back on? lift the chain and spin the cam?
You need to get #2 to TDC to check timing. I'd pull the camshafts without turning any further with a loose cam chain. Hold the cam chain up while turning to #2 TDC so the chain doesn't get wedged in below the crank gear and don't drop it down the slot. After the piston is in correct timing position reinstall the cams and make sure you have a working tensioner holding the chain tight. Then you can turn the engine over a few turns with wrench to see if all is good to go and then cranking with starter for a compression check should confirm valve condition, thumb over the hole check should tell you if you don't have a gage. GS engine timing if you don't have manual yet:
(http://www.gs500.net/gallery/data/500/gs500signalgenerators.jpg)
Only timing I have ever done is with a timing light on my old bike. However, I think with the GS it is most likely a governor plate with tick marks that have to match up (never been into the gs motor) T for Top dead center, and 1F for retarded firing point, stuff like that. The manual should have a good description of it. I dont have one :(
Hmmm that sounds backwards. But that is probably just cause the timing is off. One more definite way to tell if your exhaust valves are good is to remove the exhaust and look through the exhaust like this:
(http://i1329.photobucket.com/albums/w549/Jaco20sikkness/IMG_20130727_110800_zps748259d9.jpg)
This valve is in the seated position. The other should just be sitting there as well.
Not at home now but if the tip of the valve broke would I be able to see that or would the funnel portion have broken right off and fell in?
If the cam chain tensioner is not in or is compressed, the chain will jump when you turn over the engine. It is very possible you did not hurt anything, you just need to remove the cams, reset the timing and install the tensioner correctly this time.
Ok got the cams out and bagged.
Pulled the exhaust off and both valves are there...
All buckets and shims spin freely. No valve shims are forced upward or out of their spot...
Now if I do as GSJack said there should be no pressure on the valve due to the cams being removed correct?
So the right piston is almost top dead center.. I made the post above and went back out to check all valves.. the cams are out so the valves should all be seated correctly I figure..
Intakes look good ( a little sludged up, but thats been there when I bought it).
The right valve is seated and looks good..
I check the left valve and its not seated.. its almost seated but there is a small gap..
I check again and I see the crack..
I am stopping here until more guidance.
I presume I need to pull the head at this point?
From looking down the spark plug hole I see literally no marks on the piston at all. I cant see the whole piston but I see no marks on what I can see.
Is it possible the valve either bent and caused this crack, that this crack was already there, or that the valve is indeed broke and I may need a new head and valves?
(http://i1002.photobucket.com/albums/af147/Snake2715/IMAG1830_zps057f4fab.jpg)
(http://i1002.photobucket.com/albums/af147/Snake2715/IMAG1827_zpsc3af576a.jpg)
So pull the head at this point?
the guide sure looks cracked to me. only my opinion but should be serviced. with cams removed, are all 4 valve buckets sitting same hight inside the head? meaning both exhaust valves appear to be same height and both intakes seem to be same height? either way, i would still get that guide replaced, perhaps freshen the valves with new seals and a good lapping as long as everything is straight.
Thank you so I should remove the head?
I did a once over earlier and all shims seemed to be sitting the same, but I can go back out tomorrow after work and give it a really good look and will post my findings.
This is so crazy the piston at TDC was the other side of this valve guide.
Should I put it back together in time to make sure i have compression or at this point pull the head and see what she looks like?
Mmmm, from memory without rereading, right cyl near tdc, right intake valve guide cracked but valve looks seated, no visible marks on rt piston, left intake valve looks to be not seated, but all buckets spin freely so not held open by stuck bucket.
Strange, maybe one more check before pulling head, pour some water in the valve ports to see if it leaks thru to piston to check valve seal; have not done this myself but others here have. Think I'd test the right ones as it sits and then slowly turn engine with wrench while holding cam chain up to get left piston up so you can see thru plug hole after pouring water into left ports.
It seems strange your right intake valve guide would be cracked while the left one where you think you see the open valve is not cracked. By the way, my exhaust guide where the valve broke had half the tip broken off and the piece was long gone thru the exhaust when I pulled the head so I never saw the piece. What was left was solid so I left it like that, it's common practice to grind off those valve guide tips to increase flow thru the ports when making performance mods to engines so I wasn't too concerned about it, 70k trouble free miles later I'm not concerned about it at all. :icon_lol:
Still wondering if it's common for GS valve guides to crack like that without any valve damage causing it, has anyone else seen this happen?
If your going to replace the cracked valve guide you are probably going to replace the seals and lap the valves. Hell you might as well replace your piston rings. If so, no need to do the water leak test, you can wait till after you do all that work.
Besides, your main problem looks to be the cracked guide, so a valve leak test wouldnt do anything for you at this point.
Wasn't thinking water test before pulling head, was thinking test instead of pulling it. Guess I don't look at the cracked valve guide as being the main problem, whether a valve is broken/bent or not is. Half of the tip of my guide was broken off when the valve broke and I let it go 8 years and 80k miles ago without a problem so far.
It could be a problem if the tip of the guide broke off later and caused some damage in the cylinder, mine was an exhaust guide so the piece disappeared without going thru the combustion chamber. That's why I asked if it's common for GS valve guides to just crack like that without any valve damage causing it, has anyone else seen this happen?
Anyone?
Quote from: gsJack on August 12, 2013, 08:27:14 AM
Mmmm, from memory without rereading, right cyl near tdc, right intake valve guide cracked but valve looks seated, no visible marks on rt piston, left intake valve looks to be not seated, but all buckets spin freely so not held open by stuck bucket.
To correct this:
The intake valves all appear seated. The right valve is seated or appears so, its guide is ok. The
left valve (piston is down as of now) is actually the one with the cracked guide and does not appear seated.
I did not touch a thing after the chain went slack. There is no way that the left piston hit that valve when I turned it by hand as its in the downward position and as soon as the chain went slack I stopped. I made no more rotation... now if the left piston smacked that valve when I cranked it for a split second.. that may be possible. I am not sure if this is a newly created problem or if I stumbled on it (the cracked guide)....
Updated first post, I will continue to do this as I progress so its easy to see my current status.
I cannot say enough how appreciative I am of all who are helping here. This is new to me, and I am glad to have the forum around. I will have no problem digging in and getting the work and parts needed. Just really like the idea of the members insight as I do this.
I presume the manual will be here in a few days time, but for the time I wil continue to make progress on it.
Of interesting note.. that is the exact and only shim I replaced when I did my valve adjustment... :
http://gstwins.com/gsboard/index.php?topic=63467.msg752485#msg752485
Quote from: Snake2715 on August 12, 2013, 11:32:08 AM................................The intake valves all appear seated. The right valve is seated or appears so, its guide is ok. The left valve (piston is down as of now) is actually the one with the cracked guide and does not appear seated........................
OK, good news I think, both intake valves appear seated, the right
exhaust valve appears seated, the left
exhaust valve is the one with the cracked valve guide and doesn't appear seated.
I'd proceed with the water valve check and if it looks good put in cams and tensioner and proceed with a compression test.
If that exahust valve is not seated what happens then? I presume low compression on that cylinder?
I would still need to replace that valve or guide I presume then? Possibly even that seal?
I will research the water test and perform that then.
if the cams are not in the engine and a valve does not appear to be seating, then as the Red Queen says " OFF WITH HER HEAD!" at least one valve needs servicing to run again. HOWEVER........................................... that is the quick dirty way. service the entire head at one time, Even if you chose to replace the head, i would still have the replacement head re worked... the valve seats dressed (as i dont own the tool i would have a shop do it) along with checking and replacing any valve guides seals and laping in the valves.
um jack, the liquid test is done with head off the engine mainly so it can be cleaned up and not find its way into the crank case via piston rings. often a liquid like petrol,acetone,paint thinner is used instead of water so it will completely evaporate
Quote from: Blueknyt on August 12, 2013, 06:28:57 PM
if the cams are not in the engine and a valve does not appear to be seating, then as the Red Queen says " OFF WITH HER HEAD!" at least one valve needs servicing to run again. HOWEVER........................................... that is the quick dirty way. service the entire head at one time, Even if you chose to replace the head, i would still have the replacement head re worked... the valve seats dressed (as i dont own the tool i would have a shop do it) along with checking and replacing any valve guides seals and laping in the valves.
um, thread title starts with
Broke a valve while.................but we have yet to see any indication of a broken valve. Now we have a valve that
does not appear seated but Snake still asks
If that exhaust valve is not seated.............If that were my engine I would now want to confirm whether or not that valve might be bent before pulling the head. I've looked at the two pics Snake posted looking into the port I can't tell whether or not it's seated. Can you? I would test the left exhaust valve seal with water and if it leaked " OFF WITH HER HEAD!"
If not I would turn the engine the small distance required to get the right cylinder on the timing mark, install cams properly timed, and make sure the chain tensioner was installed and functioning. Now the engine can be turned a couple turns to check it and then cranked for a compression test. If it passes button it up and go for a nice ride, if not " OFF WITH HER HEAD!"
There have been suggestions to lap or grind all the valves, replace all the valve seals, and even put in new rings while in there. The engine only has 8800 miles on it! I'd replace the bent valve lapping it in and be done with it. In fact that was what I did when my 02 had a broken exhaust valve caused by a tight bucket at 20k miles, I replaced the broken valve and it is about to turn 100k miles now with no further engine problems.
Quote from: Blueknyt on August 12, 2013, 06:33:41 PM
um jack, the liquid test is done with head off the engine mainly so it can be cleaned up and not find its way into the crank case via piston rings. often a liquid like petrol,acetone,paint thinner is used instead of water so it will completely evaporate
um, in this case I'd test it on the engine at least the suspect valve and maybe all. A little water won't hurt it, water is a natural byproduct of internal combustion and water in the oil is natural until oil is hot enough to burn it off. I'd change the oil after it's all done and buttoned up, preferably before start up.
My 02 may be the first GS I've pulled a head on but not the first bike and I started overhauling car engines 65 years ago. I could tell you stories about things like putting the wrong head gasket on a car engine and filling the crankcase with water but I won't bore you with that stuff. :icon_lol:
Jack, i love ya brother. we are just 2 diff schools of thinking on it. I wont leave a cracked valve guide to chance, the head comes off my bike toot sweet. its worth a gasket set to me to replace the valve guide and service the valve that sits in it. for giggles i will toss on fresh valve stem seals as a set and check the seating area of the other valves with some prussian blue. might re lap them all if im feeling anal about it. so, take it for what its worth. its my 2cents
Final decision is Snakes on which way to go, it's his bike and he has to live with it. We can only advise what we would do. :thumb:
love all the info. i will be back on this shortly.
I am most likely going back to old ways and will pull the head. I can see the gap around that valve so its not seated. I do know that.
I don't know which of this work I can do and which my local shop gets. That I will figure out when I pull the head.
the water/naptha/whatever test on bike is very good advice. you can use a drinking straw to only place a few drops directly on the valves, then look through the spark hole for evidence. if you use something like radiator coolant and a black light... bam, it can't hide. don't let it sit though, do it, then flush with fuel or oil, and dump the oil afterwords, before running the engine.
lots of bikes have cracked valve guides, for who knows how many miles.
if you do pull the head, flip it upside down and fill the depression of the head with a penetrant oil, then watch the runners for drips. any sign of leaks =bad valve faces and or seats. mark the leaky ones with paint pen, and check it again a few thousand miles later on the bike as described above. if there is a lean condition, it will do similar damage again quickly.
I know I am late to this thread but I think the valves in number two hit each other due to extreme cam chain slack. That could be the reason the guide is cracked. It would also explain the exhaust not seating, and the poping noise as they hit, and were forced past each other. Chances are the intake and the exhaust valves are both bent. If the valve hit the piston, the mark could be extremely tiny. The size of an ant or smaller. That's hard to see looking down a plug hole. You can do a compression test but you could also do further damage if that exhaust valve is bent and stuck open and/or, not moving correctly. If it were me, unfortunately, that head has to come off at a minimum. Good Luck
Engine was sitting with cams and tensioner removed and right piston near TDC and Snake was reporting both intakes and right exhaust seated but left exhaust questionable. I suggested the water test (best described by ohgood above) be done to check status of left exhaust valve before turning crank and assembling cams and tensioner for compression test, was still questioning removing head at that point until status of left exhaust was confirmed. Snake has now reported the left exhaust is open and all are now in agreement so "OFF WITH HER HEAD!"
"OFF WITH HER HEAD!" is a creation of Blueknyt but not copyrighted. :icon_lol:
off with her head..
So what do I do with cam chain exactly?
Back (carb side) cam chain guide stay in or remove the bolts and it before pulling head?
lastly...how do i separate the top and bottom of the head? it seems to want to come off together.. I have that front bolt off by the exhaust... pry it apart in a fin? tap on side with a rubber mallet?
"OFF WITH HER HEAD!" is a creation of Blueknyt but not copyrighted. :icon_lol:
just wanna state that i used a quote from a charactor in a story, i in no way take credit for the creation of said quote fictional or otherwise...
as to the chain and tensioner, remove the tensioner, I used a bit of wire coat hanger in the link of the cam chain the first time to make sure i could fish it out if it fell deep, but it doesnt go far into the valley if you let it drop and you can easely fish it back out. small bolt front of engine between exhaust ports , remember to remove that one? dont think there is one by carbs, not on this engine anyway. then book says use a rubber hammer gently on sides to bump the head and seporate from the cylinders :technical: . just be careful and take your time. you dont want to marr the head or break anything
ok good so I can let that chain drop, but need to be able to fish it out. soon we will see what lies beneath....just not tonight.
Pics galore in the updated first post...
So I take it I need to do a leak test now with the head off?
Hows it all look?
Somebody correct me if I am wrong but I think I can see a shiny spot on the intake valve where the exhaust valve nicked it. I don't think the piston is involved. But then, I never thought it was. :nono: I think this is a case where the valves hit each other due to excess cam chain slack.
Decision time now before proceeding. Blueknyt seems to feel strongly about replacing that cracked exhaust valve guide but I'd let it go as I did with my own and and then had another 80k trouble free miles with a piece of that guide tip missing. ohgood whose opinions I value in these matters offered:
Quote from: ohgood on August 14, 2013, 06:23:00 AM
lots of bikes have cracked valve guides, for who knows how many miles.
Also, you mentioned buying a new head gasket but didn't mention the cylinder base gasket which many feel should be replaced when it's disturbed by pulling the head. I didn't replace it when I replaced a leaking head gasket on my CM400 years ago but did replaced it when I repaired my GS500 broken valve and it leaked a wee bit on both which doesn't bother me as much as it might you.
Your bike, your choice now. Finally the Proof:
(http://i1002.photobucket.com/albums/af147/Snake2715/IMAG1854_zps3ff135f4.jpg)
If that were my engine I'd do it like I did mine, it has less than 10k miles on it, repair the damage an get riding again. Little need for a water test now, replace the bent valve and lap in all 4 of the valves to confirm good valve seal on all. You'll need a valve spring compressor to r&r the valves. Clean up the carbon as good as possible all around and put it back together.
I wouldn't bother to change the valve stem seals either, didn't replace them on my own bike and am at 99.5K miles now with no signs of a valve seal problems. The old, tired, worn, rings are a different story that I think I should report on soon. :icon_lol:
Others would disagree and recommend further work while you have it apart and I'd welcome their opinions.
Ok heres the questions:
For Tools I need:
Valve spring compressor:
http://www.amazon.com/motorcycle-valve-spring-compressor-tool/dp/B004NV21YA/ref=sr_1_11?ie=UTF8&qid=1377214142&sr=8-11&keywords=valve+spring+compressor
Valve Lapping Tool:
http://www.amazon.com/Lisle-21200-Small-Valve-Lapper/dp/B0009OR99C/ref=sr_1_1?ie=UTF8&qid=1377214173&sr=8-1&keywords=valve+lapping+tool
Prussian Blue:
http://www.amazon.com/Permatex-80038-Prussian-Blue-Tube/dp/B000HBM86Q/ref=sr_1_1?ie=UTF8&qid=1377214268&sr=8-1&keywords=prussian+blue
Valve Grinding compound:
http://www.amazon.com/Permatex-80036-Valve-Grinding-Compound/dp/B0002UEOMS/ref=sr_1_3?ie=UTF8&qid=1377214308&sr=8-3&keywords=valve+compound
For OEM Parts I need:
Cylinder Gasket 11241-01D00
Cylinder Head gasket 11141-01D11
VALVE, EXHAUST 12912-01D00
Valve Guide 11115-45740
Valve Guide Ring 09381-10003
Do I need to replace these parts?:
O RING, CYLINDER HEAD
Part# 11143-06B00
Copper washers between the head and bolts?
On "Bent" valve do I need to replace the seat, oil seal, springs retainer, cotter valve? Or wont I know until its off, or should these be ok?
What is recommended to clean the carbon off the pistons and head anything specific? I watched a guy use oven cleaner once on a car engine but have no idea if that was a good choice.
Also I presume I should remove the valves and inspect and post here before placing my oem parts order. Are the tools listed above what I need to do the job?
I have already given my advice in prev posts, jack and I are 2 diff schools on how to treat it. you are going to have to choose for yourself on what you should do. If you havent yet, get a repair manual as it can answer alot of questions. I will not get into a info tug of war with another twins member whom i respect. i will just agree to dissagree.
I'd order a head gasket including the four o-ring seals, the cylinder base gasket, and the exhaust valve. I didn't replace the copper washers under the bolt heads although some do. Should be all the parts you need, might as well get them on the way. If something turns up later you can get it later.
I borrowed a valve spring compressor from my son, got a tube of valve grind compound locally, and lapped in the valves turning them with my thumb.
I see you are ordering a valve guide, I've never tried changing one and would probably take it to a shop to be done if I had too but didn't feel it was necessary when I did mine. I wouldn't have the shop grind seats unless you find them really bad, you will loose valve adjustment range you might need later. Your valves/seats on your low mileage engine should be good as new with the lapping.
If you'd feel better putting in new valve stem seals do so, they only cost a few bucks and it will be easy to do while you're lapping the valves.
I used a scraper and a wire brush to clean carbon as good as possible in my current non electric garage. In the auto garage we used a wire brush in a drill motor to clean carbon out of the combustion chambers and brushed the valves clean with a big wire brush on a bench motor.
Final decisions can be made after you take the head apart and confirm the condition of the valve and seat faces. I agree with Blueknyt's suggestion to get a manual, it will answer most of these questions for you.
Yes, guides typically are best installed by a shop, they are pressed in much like the valve seats are. But mainly as they have the tools on hand to knurl or ream the guide to fit the valve should it malform any during installation and thus insuring proper fitment to the stem. its also alot easyer to let them remove the broken guide as they are less likely to damage the head doing so.
Replacing guides and seats is not something to try at home. Seats and their faces need to be machined true to the guide after fitment.
http://classicmotorcycles.about.com/od/technicaltips/ss/Replacing-Motorcycle-Valve-Guides.htm
http://www.enginebuildermag.com/Article/58992/valve_seats__machining_guide.aspx
And to not discount cheetahman maybe I should test the intake valve on that side for leaks?
Not sure how I can do that really given the exhaust is not seated and when i fill the depression with fluid it will leak out the exhaust valve...
If I pull the intake valve should I be able to tell if its bent? Or would the prussian blue on the valve and seat tell me if its bent?
Just some thoughts before I place my orders. I may also check if a valve tool is available locally for rent.
Lapping the valves will confirm they are not bent and are sealing. You can if you want turn the head with the port up and put water in the port to test seal. cheetahman is probably right on suggesting the valves clashed. My intake was knicked on the edge but not bent when the exhaust broke caused by exhaust being held open by stuck bucket and not due to loose chain as in your case.
Quote from: Snake2715 on August 23, 2013, 05:37:15 AM
If I pull the intake valve should I be able to tell if its bent?
Only if you can detect 0.01mm by eye :D
You need to check the stem (in several places), the face and the seat for run-out with a DTI
Decent shops use a jig like this one..... (http://www.ryanbrownracing.com/pics/Valve_Inspection1.gif)
If you want to do a leak test with a valve missing plug the exit with putty and DONT use water, use paraffin, it penetrates better than water, it doesn't cause rust and it wont cause any harm if it finds its way into the engine :thumb:
Soo.. should I just replace the intake and exhaust valves. I mean maybe thats easier than paying a shop to check that valve?
Quote from: gsJack on August 23, 2013, 06:15:43 AM
Lapping the valves will confirm they are not bent and are sealing. You can if you want turn the head with the port up and put water in the port to test seal. cheetahman is probably right on suggesting the valves clashed. My intake was knicked on the edge but not bent when the exhaust broke caused by exhaust being held open by stuck bucket and not due to loose chain as in your case.
Quote from: gsJack on August 23, 2013, 10:55:36 AM
Quote from: gsJack on August 23, 2013, 06:15:43 AM
Lapping the valves will confirm they are not bent and are sealing. You can if you want turn the head with the port up and put water in the port to test seal. cheetahman is probably right on suggesting the valves clashed. My intake was knicked on the edge but not bent when the exhaust broke caused by exhaust being held open by stuck bucket and not due to loose chain as in your case.
You cant effectively lap a bent valve Jack....... think about it.
Ask yourself a question.........what is going to happen as the valve rotates in its guide if the sealing face is not at exactly 90deg to the axis of the guide :dunno_black:
This is the procedure below, anything else is guesswork. Note the service limit is 0.03mm, or just over 0.001"
http://www.motorcycleinstitute.info/suzuki-gsx400f/valve-stem-runout.html
Shops use the jig/DTI method for good reasons, its quick its simple and it removes all doubts
I wouldn't be happy with a cracked guide, cracks have a nasty habit of spreading!
O/P??
Used GS5 heads are not exactly thin on the ground.....personally I would find a good one, clean it up, lap the valves, fit 4 new seals and set the clearances BEFORE fitting it to the engine but hey.......its your bike,time, money etc etc
Quote from: sledge on August 23, 2013, 12:00:46 PM
Quote from: gsJack on August 23, 2013, 10:55:36 AM
Quote from: gsJack on August 23, 2013, 06:15:43 AM
Lapping the valves will confirm they are not bent and are sealing. You can if you want turn the head with the port up and put water in the port to test seal. cheetahman is probably right on suggesting the valves clashed. My intake was knicked on the edge but not bent when the exhaust broke caused by exhaust being held open by stuck bucket and not due to loose chain as in your case.
You cant effectively lap a bent valve Jack....... think about it.
Yea bent = cant be lapped ... therefore lapping a valve = not bent ...
However I dont like lapping @ all ... 3 angle cut is far better and around here pretty cheap, car engine shops will gladly do it for you on a bike head.
Cool.
Buddha.
"Jack....... think about it"
:icon_lol: :icon_lol: :icon_lol: :dunno_black: :cookoo:
" 3 angle cut is far better"
The valve still gets lapped, the extra angles is to smooth the flow from port to chamber and vice versa past the narrowest contact point of the valve face and seat.
Quote from: gsJack on August 23, 2013, 01:16:16 PM
"Jack....... think about it"
:icon_lol: :icon_lol: :icon_lol: :dunno_black: :cookoo:
I am sorry old son.......but `guesswork` and the `if it looks ok it is ok` way of diagnosing faults and identifying issues are not methods I generally follow and certainly and more importantly not methods I would recommend to others.
However.......... I appreciate you dont share my way of thinking :dunno_black:
I'm not guessing at anything. Lapping in all valves will prove them to be straight and to have good seal, if they won't lap in a bent one will be obvious and will be replaced. You should be able to comprehend that! Buddha tried to point that out to you above:
Quote from: The Buddha on August 23, 2013, 12:04:21 PM
Yea bent = cant be lapped ... therefore lapping a valve = not bent ...
Cool.
Buddha.
errr... way i read it ...you both mean the same thing... just different approaches/descriptions to how/what process to identify and correct..
bend/s at any point mean they cant/shouldnt be used... ??!
lapping with a machine/lathe/whatever the heck is the name for the thing .. should show if its bent? .. if it is able to be lapped then it cant be bent!?
its a self identifying process to me...
like having any less than perfectly centred item on a lathe .. the eccentric rotation will show itself ..
:dunno_black:
Jacks version has the lapping showing the eccentric motion ... Sledges version has the Jig testing showing it ...
then again ive not done either... and have the temerity to say something about the process... so :icon_rolleyes:
Post deleted. Personal attacks against Moderators will not tolerated.
Quote from: gsJack on August 23, 2013, 10:04:38 PM
I'm not guessing at anything. Lapping in all valves will prove them to be straight and to have good seal, if they won't lap in a bent one will be obvious and will be replaced.
But Jack?.......take it a stage further, what will a bent valve do to a sound seat when you try to lap it?
Have you ever actually seen the outcome?.......Here is an example for you or for that matter anyone else that is interested :thumb:
(http://i44.tinypic.com/znaaes.jpg)
Notice the wall and face thicknesses at the indicated points.
I don't know if the person concerned actually managed to get a seal but what is obvious and cannot be denied is that the seat was ruined in the process
Care to comment, or do you believe off-centre seats are acceptable? Maybe it wasn't an issue back in your day, I dunno, like you say I wasn't around back then :dunno_black:
So lets summarise, do it the quick easy and recognised way using a DTI, or do it your way and take the seat out in the process.
For the benefit of the younger and less experienced amongst us I suggest somewhere back there you add a disclaimer, something along the lines of this should do.....
**WARNING**...Following my methods may result in you having to replace an otherwise sound seat, following manufacturers and professional engine rebuilders recommended methods wont.......its your call :thumb:
:D
I have related to the OP how I repaired my then 02 low mileage GS head by replacing it's broken exhaust valve, lapping the mating intake valve to confirm it's seal, and putting it back together with new head and base gaskets. It's run like new for another 80k miles since the repairs so I'm satisfied with them.
If the OP choses to believe your distorted off center picture as the possible result of a quick lap to check seal then I think his choice might be to just get a new intake valve for left cylinder with the bent exhaust valve as he has suggested himself and be done with the problem. His bike, his choice.
In the meantime I have wasted more than enough time on this thread and on you and am done with both. If anyone else cares to offer their opinions to the OP on this repair please do so. I'm going to go put some more miles on my nicely running 02 GS to get it over the 100k mile mark only a few hundred miles away. It's rings are getting quite tired but it's valves are still ready to go! :thumb:
I agree jack.
Let the people decide.
Coming up next week.........How to bore a straight hole with a bent drill bit :D
Sorry I have been not been reporting here and thanks all for the input. Life gets crazy sometimes and I didn't get back to this as soon as I had originally planned.
OK so the intake is also leaking with the liquid test. I filled the port and let it sit on its side and it did slowly leak. I think at this point I should just replace it and be done. So both left valves get replaced. The right intake actually was fine as I filled it with liquid while I was at it, no leaks.
I will call a shop I am familiar with in the morning and get the guide price quoted and the parts on their way. I can rent a valve removal tool and will do so. The valve seals I may replace as well I will decide when putting my OEM order together depending on totals.
I am going to order:
Base Gasket
Base Gasket orings x4
Head Gasket
Intake Valve
Exhaust Valve
Valve Guide
Guide Ring (do idea if this is reusable so will get new)
Valve Seals X 4
I assume that once I get this done I will have to re assemble then check clearances and then once again potentially replace shims, such is life.
"I assume that once I get this done I will have to re assemble then check clearances and then once again potentially replace shims, such is life."
yes you will, and check all 4 on clearences once the head is installed and torqued to spec
OEM replacement valve guides come with a slightly increased outside diameter. This is to compensate for the now slightly increased pilot hole diameter and the reduction in interference caused by knocking the old one out so in theory they shouldn't need knurling before fitting.
Its not been mentioned yet but you may as well check the spring lengths while they are off, especially if you have racked up the mles or are `rev-happy` I cant remember the service limit figures but they will be in the manual. I think its around 35mm for the inner and 40mm for the outer. Anything less means they have gone soft and must be replaced.
Note how the valve springs come off, there is a right way and a wrong way to fit them. The closer pitched turns must go towards the head. You may find a dab of paint on the upper (cam) side that's serves as an indicator.
Again its not been mentioned but its usual to coat the replacement valve with molybdenum or high temp grease before fitting it into the new guide, this helps it bed in.
Quote from: Blueknyt on August 23, 2013, 05:54:05 PM
" 3 angle cut is far better"
The valve still gets lapped, the extra angles is to smooth the flow from port to chamber and vice versa past the narrowest contact point of the valve face and seat.
They never truly lapped it, I saw them do iy a few times. No operation with valve in the seat.
They cut the seats.
They cut the valves.
They put some marker compound in the thing and put the valve in the seat and press it with their thumb, and look for contact ring.
Then, repeat the cutting if its not right.
They get machined to match - :D
Cool.
Buddha.
Quote from: The Buddha on August 26, 2013, 06:29:36 AM
Quote from: Blueknyt on August 23, 2013, 05:54:05 PM
" 3 angle cut is far better"
The valve still gets lapped, the extra angles is to smooth the flow from port to chamber and vice versa past the narrowest contact point of the valve face and seat.
They never truly lapped it, I saw them do iy a few times. No operation with valve in the seat.
They cut the seats.
They cut the valves.
They put some marker compound in the thing and put the valve in the seat and press it with their thumb, and look for contact ring.
Then, repeat the cutting if its not right.
They get machined to match - :D
Cool.
Buddha.
(http://www.gs500.net/gallery/data/500/ValveSeatFinish.jpg)
Parts all ordered from RockymountainATV.com last Sunday 8/25, most shipped and were here on Wednesday and today...
Parts on backorder are until October!:
:cry:
Exhaust valve
Cylinder Head Gasket
Head Gasket Orings
Cylinder Gasket
I called Bike Bandit as well and they are on backorde there.. I know ronayers doesnt stock OEM..
So looks like I am on standstill unless someone else knows of an online supplier that stocks OEM?
Nobody "stocks" OEM except for high turn-over parts. Oh, unless you count Adidasguy. He might have gaskets. And maybe a used valve.
i've shopped at www.partspitstop.com for a couple of oem parts for my 01. here is even a 5% off code LDSAVINGS
being that your from central mi they have a store front in plainfield(village motorsports) that you could pick it up from them.
People give up too easily :D Try typing the part # into google :thumb:
http://www.motosport.com/motorcycle/oem-parts/SUZUKI/1995/GS500E/CAM-SHAFT-_-VALVE/VALVE,EXHAUST/12912-01D00
Or.....if you are desperate enough try overseas :dunno_black:
http://www.cmsnl.com/suzuki-motorcycle_model13053/?gclid=CN2Z8ZnHp7kCFQTMtAodNWEABg
http://www.robinsonsfoundry.co.uk/content/pages/shop/parts.htm
http://www.wemoto.com/bikes/Suzuki/
http://www.bike-parts-suz.com/suzuki-recherche-bike-pieces_nn.php?compteur=918&PartsListID=487408
I may have got too late to this point ...
But get valves from kibblewhite if yo ucan ... they are generally made of better material than the stock suzi junk ...
Of course, suzu is a lot better than kawi. With a kawi, you had to have it ...
Cool.
Buddha.
looks like rockymountain is coming through. first it said backordered until 9/3 then I got an email that it was backordered until 10/4 by their customer.service team.
looks like the remainder of my order was shipped out yesterday.