Well, I'm getting the good ol' GS back on the streets after ~3 months of inactivity. She's running well, except for a very annoying rattling noiose coming from the lower part of the engine it seems. The noise is there with the engine idling, and is loudest when I'm accelerating from a stop. It seems to disappear above ~3-4000 rpm, but it's possible that it just changes frequency and I can't hear it. Here are three short videos I took today while trying to identify the origin of the noise:
Right side of the engine (http://www.stanford.edu/~dchavez/rside.wmv)
Left side of the engine (http://www.stanford.edu/~dchavez/lside.wmv)
Riding around the parking lot (http://www.stanford.edu/~dchavez/riding.wmv)
Am I in urgent need of a valve adjustment? btw, I'm at 12,400 miles (had it for the past ~3000 miles).
Thanks for the help! :icon_confused:
OMG, that doesn't sound good. I wish I knew what you needed. :dunno_white:
Are the exhaust header bolts tight? (Where the exhaust pipes connect to the engine.)
Kerry, I saw your comments/picture on another thread regarding the exhaust header bolts, so I checked before I took that video. They seem fine, at least I couldn't move the headers with my hand, but I'll double check with a wrench tomorrow.
Come to think of it the noise does seem to be coming from the lower part of the engine, so it probably wouldn't be the valves would it? :icon_confused:
Quote from: WildBlue on June 19, 2006, 10:58:28 PMCome to think of it the noise does seem to be coming from the lower part of the engine, so it probably wouldn't be the valves would it? :icon_confused:
It's driving me nuts, because the noise sounds so familiar and yet I can't put my finger on it. (Insert memory disclaimer here for being over 40. :oops:)
But no, tight valves give more of a "tick" or "tap" sound. This is a distinct "ping". We need someone with engine and tranny tear-down experience.
Quote from: Kerry on June 19, 2006, 11:20:34 PM
This is a distinct "ping". We need someone with engine and tranny tear-down experience.
Uh oh, this is already sounding like it might be major... She's not about to fall apart is she? :o
Don't get me wrong! I'm not declaring it to be a serious problem. I'm just trying to identify the sound. :dunno_white:
You sure the soundtrack is not of a tractor?
Does not sound good. Pinging from the lower end almost certainly means major overhaul. My bet is on the plain bearings of the rods.
Other plain beraings that like to crap out are those of the balancer shaft, but that's is usually the result of an installation mistake when taking off the clutch cover.
You didn't happen to run her low on oil once? The GS engine is almost indestructible, but she's vindictive: run her low on oil once and she'll never forgive you.
hey, mmm thats a familia noise, i can't place it though, does the noise lessen if you put more oil in it?
you best bet might be http://cgi.ebay.co.uk/suzuki-gs500-engine-frame-and-swingarm-and-exhaust_W0QQitemZ8076052233QQcategoryZ10534QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
£55 whats that in euros 80euros. or are you guys not on euros, your not are you??
it almost soulnds like piston slap like you have a bent connecting rod
good luck with it
Quote from: MarkusN on June 20, 2006, 12:33:45 AM
You didn't happen to run her low on oil once? The GS engine is almost indestructible, but she's vindictive: run her low on oil once and she'll never forgive you.
Nah, I've always been careful about that. There was some time when I actually ran her a little high on oil (not for long), but I doubt that'd hurt...? I did switch to synthetic on my last oil change though, but I read that the GS is cool with that.
Quote from: hmmmnz on June 20, 2006, 01:54:10 AM
hey, mmm thats a familia noise, i can't place it though, does the noise lessen if you put more oil in it?
you best bet might be http://cgi.ebay.co.uk/suzuki-gs500-engine-frame-and-swingarm-and-exhaust_W0QQitemZ8076052233QQcategoryZ10534QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
£55 whats that in euros 80euros. or are you guys not on euros, your not are you??
it almost soulnds like piston slap like you have a bent connecting rod
good luck with it
:o Are you suggesting I might need to buy a new engine??? Or wait, you mean if it turns out to be a connecting rod right? I'm not sure if more oil would lessen the noise, I checked the oil level this morning and it's just slightly under Full. What would cause a rod to bend, other than lack of lubrication? :dunno_white:
Here's another bit of information that I just remembered. Shortly before I injured my knee and stopped riding, I would hear a CLUNK when I went to start it first thing in the morning. The clunk definitely came as I recall from the lower part of the engine, around where the black Suzuki cover is, and it only happened the first time I started it in the morning (engine cold). My tachometer actually stopped working after one of these clunks - I've verified that the cable is in fact connected tightly at both ends, though I still need to check that it's not broken. Now this tachometer thing could be a coincidence, but then again it might be related.
The clunk has been replaced by this pinging/rattling noise, which is more noticeable now than the last time I rode it, so it definitely seems to be getting worse. Actually if I place my hand on the black cover I can feel a small vibration that seems to coincide with the pinging; I'll repeat this tomorrow just to be sure.
This is giving me a headache... :mad: :cry:
Clunk from which side, left or right? Goats syndrome (disintegrating alternator wheel, left) or something loose in the impulse generator (right)?
If it's on the right, take off the small cover; no oil behind that, so that's easily checked.
I'm not familiar with the newer tachs. Does the 02 already have the electrical tach? If so, something might be wrong with your impulse generator.
Thinking aloud here: Ignition generator wheel off, causing extreme early ignition? that would explain the tractor-like sound and it going away at higher revs.
Quote from: WildBlue on June 20, 2006, 02:32:38 AM
Quote from: MarkusN on June 20, 2006, 12:33:45 AM
You didn't happen to run her low on oil once? The GS engine is almost indestructible, but she's vindictive: run her low on oil once and she'll never forgive you.
Nah, I've always been careful about that. There was some time when I actually ran her a little high on oil (not for long), but I doubt that'd hurt...? I did switch to synthetic on my last oil change though, but I read that the GS is cool with that.
Quote from: hmmmnz on June 20, 2006, 01:54:10 AM
hey, mmm thats a familia noise, i can't place it though, does the noise lessen if you put more oil in it?
you best bet might be http://cgi.ebay.co.uk/suzuki-gs500-engine-frame-and-swingarm-and-exhaust_W0QQitemZ8076052233QQcategoryZ10534QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
£55 whats that in euros 80euros. or are you guys not on euros, your not are you??
it almost soulnds like piston slap like you have a bent connecting rod
good luck with it
:o Are you suggesting I might need to buy a new engine??? Or wait, you mean if it turns out to be a connecting rod right? I'm not sure if more oil would lessen the noise, I checked the oil level this morning and it's just slightly under Full. What would cause a rod to bend, other than lack of lubrication? :dunno_white:
Here's another bit of information that I just remembered. Shortly before I injured my knee and stopped riding, I would hear a CLUNK when I went to start it first thing in the morning. The clunk definitely came as I recall from the lower part of the engine, around where the black Suzuki cover is, and it only happened the first time I started it in the morning (engine cold). My tachometer actually stopped working after one of these clunks - I've verified that the cable is in fact connected tightly at both ends, though I still need to check that it's not broken. Now this tachometer thing could be a coincidence, but then again it might be related.
The clunk has been replaced by this pinging/rattling noise, which is more noticeable now than the last time I rode it, so it definitely seems to be getting worse. Actually if I place my hand on the black cover I can feel a small vibration that seems to coincide with the pinging; I'll repeat this tomorrow just to be sure.
This is giving me a headache... :mad: :cry:
That is very interesting. The clunk you describe sounds like a hydro lock, or water in the cylinder. It reminds you of a bad starter, it starts to crank and then "clunk" .This would make perfect sense if you had a liquid cooled engine, but obviously that is not the case. Is there anyway you got water or another liquid in your engine? Usually a hydro lock will bend the conecting rod and give the exact sound that you are now having. My guess would be either bent conecting rod or bad main/conecting rod bearing(s). When you rev it slighlty the noise should kind of go away and then when you let off the gas it should get louder until the revs come down. Does this sound familiar? :dunno_white:
Well, hydrolock is possible in the GS if the carbs overflow and she's standing slightly pitched to the front. It's not exactly "hydro"-lock then, it's fuel-lock.
Quote from: Jason on June 20, 2006, 06:40:51 AM
That is very interesting. The clunk you describe sounds like a hydro lock, or water in the cylinder. It reminds you of a bad starter, it starts to crank and then "clunk" .This would make perfect sense if you had a liquid cooled engine, but obviously that is not the case. Is there anyway you got water or another liquid in your engine? Usually a hydro lock will bend the conecting rod and give the exact sound that you are now having. My guess would be either bent conecting rod or bad main/conecting rod bearing(s). When you rev it slighlty the noise should kind of go away and then when you let off the gas it should get louder until the revs come down. Does this sound familiar? :dunno_white:
Hey Jason, that does sound familiar. You can actually hear it on the third video where I rode it around the parking lot. As I accelerate from a stop it gets louder until I come up to speed, then it sort of disappears, then as I slow down it gets louder again until the revs come down, then it's still there at idle as you can tell from the other two videos, but not as loud.
Hmmm... so could someone explain what hydro lock is exactly? How does water cause the *clunk* and subsequently the bending of a rod? I'm trying to think but I can't recall ever getting water into the engine. I mean, when I wash her I do hose the outside of the engine, avoiding the spark plugs, but that's about it.
Quote from: MarkusN on June 20, 2006, 06:50:38 AM
Well, hydrolock is possible in the GS if the carbs overflow and she's standing slightly pitched to the front. It's not exactly "hydro"-lock then, it's fuel-lock.
I see... I still don't understand, how would this fuel-lock work? What is getting locked? Sorry for the noob questions, I guess I'm not familiar enough with the engine of the GS. :icon_rolleyes:
Oh, one other thing. During the time when I was hearing the *clunks* there was white (or maybe light blue) smoke coming out of the exhaust after the first start of the day, until the engine warmed up. I always assumed this was a sign that I overfilled with oil, and it was in fact a little over the F marking for a while, but I corrected that at my last oil change and the smoke went away.
So here's another question, is it possible that running the engine with a little too much oil could've caused this hydrolock that you speak of? It's the only fluid that I can think of that could've gotten into the cylinders.
Hydro lock is liquid (usually antifreeze in liquid cooled engines ) that gets into the cylinder and lays on top of the piston. If there is enough that it has no where to go and it fills the combustion chamber it is basically trapped and when you crank the engine over the piston comes up and the liquid won't compress. So basically lets say you have a 4 inch stroke and you have 1/8 of liquid lying on top of your piston(s) now as your piston comes to top dead center the liquid will not allow the piston all the way to the top of its stroke. Something has to give and since liquid won't compress it is the conecting rod that usally gives and bend slightly. Then you get a knocking sound because the conecting rod is no longer traveling up and down straight. It basically causes the piston to "slap" off the side of the cylinder. I am not saying 100% this is what happened, but it makes sense in what you are describing happened. It would have to be torn down and checked over real good. It sounds as though you may have been getting excess oil laying on top of your pistons. How I'm not sure. I would have a good repitable mechanic listen to it as the internet doesn't always do sounds justice.
Jason beat me to it, but here's my version anyway....
As
MarkusN said, you can actually get fuel in the cylinder(s) if your carbs overflow and your bike is tilted down in the front. (Usually the fuel will overflow into the airbox and out the airbox drain hose -- see
this diagram (http://www.bbburma.net/Scans/www_gs500_de_HoseRouting.jpg) for the relative positions of things. See the downward slope of the intake boot between the carb and the engine?)
Let's suppose that fuel HAS drained into the cylinder(s). Whether or not hydrolock occurs depends on where the pistons are at in their 4-stroke cycle. For discussion purposes, I will refer to the animation in the middle of
this HowStuffWorks page (http://auto.howstuffworks.com/engine1.htm). By right-clicking on the animation you can stop or start it, go forward or backward, etc.
1) After watching the animation for a while, stop it in the middle of the EXHAUST stroke (stroke 4 - the green one).
2) Imagine that fuel has seeped into the cylinder above the piston.
3) Restart the animation and "watch" as the liquid fuel gets shoved out of the exhaust port and into the exhaust pipe. No problem! The fuel will be ejected out the back as "white smoke" or will burn right in the pipe. ("POW!")
4) Now, stop the animation in the middle of the COMPRESSION stroke (stroke 2 - the purple one).
5) Again, imagine that fuel has seeped into the cylinder above the piston. Notice that both valves are CLOSED at this point, so nothing can enter or exit the cylinder.
6) Restart the animation and "watch" as the liquid fuel prevents the piston from moving upward. ("CLUNK!") With the starter motor trying to force the piston up, and the fuel preventing it from moving up, something has to give. That something is usually the connecting rod. :cry:
Hope this helps.
Here's a trick to see if the rod is bent: Take both sparkplugs out.
Find a straight rod of some sort (shish-ka-bob comes to mind (it's almost lunch...)).
Put the rod into one of the holes.
Rotate the crank by hand and measure how far up OR down that piston goes.
Then do the same for the other piston/cylinder.
If the measurements are different = you have a bent rod.
unless you're fortunate enough to have connecting rods that have been bent by exaclty the same amount :)
Quote from: Kerry on June 20, 2006, 12:05:07 AM
Don't get me wrong! I'm not declaring it to be a serous problem. I'm just trying to identify the sound. :dunno_white:
Sounds like your bike from the video when you left the test shim in. O0
Thanks for all the advice and explanations so far! The animation did help visualize hydrolock, just thinking about it is :o. Poor engine.
I went out and tried Scratch's trick, and here are the results: there does not seem to be a difference between the left and right sides. The stroke seems to be almost exactly 3" (plus or minus 1/16"), as shown in the following 2 pictures. I repeated the measurements twice, the first time was with me sitting on the bike and rolling it back and forth in 6th gear, the second was with the bike on the centerstand and rotating the rear wheel manually:
White background:
(http://www.stanford.edu/~dchavez/GS500/ruler1.jpg)
Black background:
(http://www.stanford.edu/~dchavez/GS500/ruler2.jpg)
Here's how I did it (other newbies might find this helpful). I used wooden skewers from the local grocery store, and made marks with a Sharpie at the top and bottom of the stroke:
(http://www.stanford.edu/~dchavez/GS500/skewer.jpg)
(http://www.stanford.edu/~dchavez/GS500/howto.jpg)
Left spark plug:
(http://www.stanford.edu/~dchavez/GS500/lspark1.jpg)
(http://www.stanford.edu/~dchavez/GS500/lspark3.jpg)
Left spark plug comparison with a new spark plug:
(http://www.stanford.edu/~dchavez/GS500/lnew.jpg)
Right spark plug:
(http://www.stanford.edu/~dchavez/GS500/rspark1.jpg)
(http://www.stanford.edu/~dchavez/GS500/rspark3.jpg)
Right spark plug comparison with a new spark plug:
(http://www.stanford.edu/~dchavez/GS500/rnew.jpg)
One other thing I noticed is that my chain is too loose and needs to be adjusted. I don't think this would cause noise with the bike stationary though... (?)
Sooooooo, these results suggest that it might not be a bent rod? What do you guys think? :dunno_white:
Scratch, I just sent ya a PM... :thumb:
i had a simular sound on my cbr, the stator bolts had backed out after 11 years, and = bad things. new stator, flywheel and cover. i would pull both side covers off and check. if nothing wrong all you need is a new gasket for the left engine cover.
The clunk you heard when you started your bike cold has to do with the sprag gear that drives the pump. Starwalt has more experience in its function, but when its cold and the gear is worn then it jumps out to engage the gear train combo that the pump is on, but the force of the thick viscous oil makes it really hard to engage and it slips of the teeth and goes back in, that is the clunk, at least that is what someone here described a while back. Let me do a search
How is your chain Tensioner?
Does the sound disapear after getting up to higher speeds?
Here is a link to pictures of what is under your LH crankcase cover, something might have come loose in there
http://home.bellsouth.net/p/s/community.dll?ep=331&folderid=180855&groupid=41309&folderview=thumbs&ck=
sounds like a harley :laugh:
Quote from: mike_mike on June 20, 2006, 07:55:23 PM
sounds like a harley :laugh:
Hey. Stop picking on my GS. :nono: :icon_razz:
Quote from: Catcams on June 20, 2006, 06:48:59 PM
How is your chain Tensioner?
Does the sound disapear after getting up to higher speeds?
The chain is a bit loose and needs tightening, I verified this yesterday while checking for a bent rod. I need to fix it, but that wouldn't cause any noise when the bike isn't moving would it? :dunno_white:
Quote from: rangerbrown on June 20, 2006, 04:25:26 PM
i had a simular sound on my cbr, the stator bolts had backed out after 11 years, and = bad things. new stator, flywheel and cover. i would pull both side covers off and check. if nothing wrong all you need is a new gasket for the left engine cover.
Quote from: coll0412 on June 20, 2006, 06:53:19 PM
Here is a link to pictures of what is under your LH crankcase cover, something might have come loose in there
http://home.bellsouth.net/p/s/community.dll?ep=331&folderid=180855&groupid=41309&folderview=thumbs&ck=
Hmmm, I see... so it seems like I might be able to have a look if I remove the crankcase covers, starting with the left one then? Stoopid noob question: do I need to empty the oil from my engine before I do that? I do, don't I... Actually I should look it up on my Clymer (I have a Haynes coming in real soon btw, it's been highly recommended).
tough problem! i have a question for the experienced engine gurus: if a connecting rod is bent, how much of a difference between the cylinders would be observed? would the kabob skewers as shown in the pictures be able to detect the difference, if it was small enough? i mean, if you're trying to find a difference of 1/32" with sharpies and rulers it may not work out so well. can the the depth-gauge part of a dial caliper fit into the spark plug holes? this may give you a measurement accurate to within 0.005-0.010" or so.
i guess you'd have to be careful not to scratch the pistons with the metal caliper. how bad would it be if you did scratch the piston?
i would drain the oil, but save it and check of any thing that shouldn't be there. (metal)
the rod's, if they were bent it would show in as little as 1/16 in or more, till it snaps any way.
but remeber, there could be corbon build up that is in dif thickness that could throw it off. but if it were bent you would know it very, very shortl after happening, as it throws the balance off.
Quote from: che mike on June 21, 2006, 12:04:59 PMi guess you'd have to be careful not to scratch the pistons with the metal caliper. how bad would it be if you did scratch the piston?
i wouldn't matter at all if you scratched the piston, chances are that covered in a layer of carbon any way.
the chain being loose wouldn't matter when your not moving, it defently wouldn't make the noice your sick bike is making.
the stator side is dry so you could check that side first and check that none of the bolts have come undone and are getting knocked around by it,
good luck
Okay, so just to be sure, if I remove the left-hand crankcase cover where the stator is there should be no oil in there? So I can do it without draining the oil from the engine, correct?
EDIT: btw, my friend and I seem to have narrowed it down to the left crankcase cover region. If you put your hand on it you can actually feel a tapping of sorts that coincides with the noise. Also when I heard the *clunk* at startup it was coming from the bottom left, I'm pretty sure. Weird stuff though, because if you get your ear close to the engine on the left side, you can hear it coming from the bottom, but if you do it on the right side, it would seem to be coming from the top. But I guess that's just the way the engine resonates or something. :icon_confused:
left engine cover will have oil in it, right engine cover should not.
Okay that makes sense. Why else would it have a gasket on it right? duh. :icon_rolleyes:
So the alternator is actually submerged in oil then? Huh, I never realized that.
yep as it is the starter gear on it as well.+ it keeps it cool or cooler thatn free air.
Well, I listened to it last night, and first I rotated it over cold, just listening and feeling as I turned the crank. As I turned it. with the plugs out, I still got resistance (from the cams no doubt), but in certain areas of the rotation it felt like grinding.
Then we started it, ooohhh, did it not sound good. It started great, started right up, but at low rpm it made a loud rotating deep clunk-a-clunk sound; definitely from the left side. Now, looking at the oil on the dipstick it looked fine, there didn't seem to be any particles in the oil, so I didn't think that it was bearings, but the sound does. When it's revved up, the clunking goes away---oil pressure must be floating whatever bearing (be it the crank or balancer).
I suggested the oil drained and the left cover removed for further investigation.
I will be calling shops in the area.
Thanks again for stopping by scratch! :thumb: :bowdown:
When he heard the low-rpm noise I thought scratch was going to have a heart attack right there. :o He was like "OOOOHHH OOOOOOHHHH, THAT DOESN'T SOUND GOOD. KILL IT! KILL IT!" *gets exorcism started* :laugh: (well, maybe I exaggerate a little, but you get the point).
So as much as I'd like to get my hopes up, everything seems to point to a bad bearing. Still, I'll take out the left cover this weekend and have a peek in there. :cry:
Quote from: WildBlue on June 19, 2006, 09:34:11 PM
Well, I'm getting the good ol' GS back on the streets after ~3 months of inactivity. She's running well, except for a very annoying rattling noiose coming from the lower part of the engine it seems. The noise is there with the engine idling, and is loudest when I'm accelerating from a stop. It seems to disappear above ~3-4000 rpm, but it's possible that it just changes frequency and I can't hear it. Here are three short videos I took today while trying to identify the origin of the noise:
Right side of the engine (http://www.stanford.edu/~dchavez/rside.wmv)
Left side of the engine (http://www.stanford.edu/~dchavez/lside.wmv)
Riding around the parking lot (http://www.stanford.edu/~dchavez/riding.wmv)
Am I in urgent need of a valve adjustment? btw, I'm at 12,400 miles (had it for the past ~3000 miles).
Thanks for the help! :icon_confused:
This is a classic example of a question you shouldn't be asking ... the answer always is ... yes ... its easy and bloody well eliminates so much guesswork.
So it does need it ... BTW I didn't click your links ...
Cool.
Srinath.
A valve adjustment is the least of his worries at this point.
I talked to Greg @ Santa Clara Cycle Accessories, they don't do engine teardowns, and he suggested Double R Cycles. Ph# 241-9850 We conjectured that maybe the generator is coming loose off the end of the crank and is wobbling around. :dunno_white:
I'll be looking up where RR Cycles is located (or I'll call).
Edit: Although, twice now has two people stated that it might be valves (valve adjustment)...I'm just thinking if it is at all possible for mal-adjusted valves to allow, or make that noise? Srinath?
your videos made me curl into a ball and cry.
I feel your pain buddy... my old gs has made that noise for months now.... btw it no longer runs on the left cylinder.... I'm sad for you!
Austin
Clunk from the left bottom end: Goats syndrome?
That's what I am thinking ... after reading more ... I replied just reading the title the first time ...
Cool.
Srinath.
Goat's syndrome is essentially an alternator tearing itself to pieces, correct? I'm planning on removing the left crankcase cover this weekend, I'll have an update then.
Quote from: KYGS500E on June 29, 2006, 05:26:17 AM
I feel your pain buddy... my old gs has made that noise for months now.... btw it no longer runs on the left cylinder.... I'm sad for you!
Austin
Hey Austin, have you figured out what's wrong with your bike?
scratch -- thanks for the info!
Quote from: WildBlue on June 30, 2006, 11:55:15 AM
Goat's syndrome is essentially an alternator tearing itself to pieces, correct? I'm planning on removing the left crankcase cover this weekend, I'll have an update then.
Quote from: KYGS500E on June 29, 2006, 05:26:17 AM
I feel your pain buddy... my old gs has made that noise for months now.... btw it no longer runs on the left cylinder.... I'm sad for you!
Austin
Hey Austin, have you figured out what's wrong with your bike?
scratch -- thanks for the info!
Right ... that's the gist of it.
Cool.
Srinath.
Well, on Saturday I decided to remove the left crankcase cover as suggested here. Everything in there looked pretty good actually, with no signs of the alternator wanting to fall apart.
The stator:
(http://www.stanford.edu/~dchavez/GS500/Picture%20082.jpg)
The rotor assembly (notice a small nick on the bottom magnet):
(http://www.stanford.edu/~dchavez/GS500/Picture%20094.jpg)
A closer look at that small damage on the bottom magnet:
(http://www.stanford.edu/~dchavez/GS500/Picture%20078.jpg)
So it seems like it isn't the alternator after all and she doesn't have goat's syndrome. That small nick on the one magnet might need some patching, but I don't think it'd cause any of the symptoms that I have.
Checked all the bolts too, and they were solid on there. I then grabbed the rotor with my hands and tried to shake it up and down to see if there was any play (potentially confirming a busted crankshaft bearing) and it didn't move at all. There was some tiny play along the axis of rotation of the rotor (probably less than 1mm), but nothing that suggested any damage. I couldn't really check the crankshaft balancer from there.
So even though there was no play in the crankshaft I suppose it could still be a bad bearing, or something wrong with the crankshaft balancer. Anything else I can check before I have the shop tear down the engine? :icon_confused: