another odd oil pressure issue

calispec · June 18, 2006, 12:50:24 PM

ok, i was having an issue with my oil pressure light kicking on at idle and then flicking off with a any touch to the throttle. So i replace the easy stuff. I changed the oil (to retellla
T 15w-40), replaced the oil filter and the oil pressure sensor). I got it up and running tody with no oil pressure light at all. Then after like 15 minutes of riding the oil light started to flicker on at idle, just barely blinking, and would shut off again with a touch of throttle.

Any ideas?

again, the bike had a new oil pump installed about 60 miles ago too.

What might it be?

sledge · June 18, 2006, 01:56:08 PM

Well like you say, you have replaced all the easy stuff. You have to now start to consider the fact that there may well be a bearing somewhere in the engine that has just about worn out. Whats the history of the bike and for what reason was the pump replaced?

GeeP · June 18, 2006, 06:26:03 PM

Test the oil pressure per the instructions in the Clymer manual. Check to see what the actual pressure is with a gauge. The test port is on the bottom Left?? side of the crankcase. It sounds like you either have a faulty oil pump, or a gasket failure.

calispec · June 18, 2006, 08:45:42 PM

I bought the bike from Jake D, he was having the same oil light issue i was and they tested the pressure and said it was low so they replaced the oil pump and the shop said the pressure came back to where it was suppose to be.

He had the engine rebuilt like 60 miles or so ago and according to the shop that did the work it was all spec'ed out from crank to valve cover.

I guess my next thing to do is to check the oil pressure with a gauge.

GeeP · June 18, 2006, 08:50:07 PM

Ahh, now I remember... Have you resolved this problem?

http://gstwins.com/gsboard/index.php?topic=27408.msg289829#msg289829

Oil pumps don't like chunks of metal!

Let's hear what the oil pressure is up to. If we keep our fingers crossed it might just be a bad pressure switch.

calispec · June 18, 2006, 11:30:37 PM

Quote from: GeeP on June 18, 2006, 08:50:07 PM
Ahh, now I remember... Have you resolved this problem?

http://gstwins.com/gsboard/index.php?topic=27408.msg289829#msg289829

Oil pumps don't like chunks of metal!

Let's hear what the oil pressure is up to. If we keep our fingers crossed it might just be a bad pressure switch.

I replaced the pressure switch this last go around and still got the same results as before i replaced it.

MarkusN · June 19, 2006, 02:28:00 AM

Could be an electrical issue. The oil pressure switch connects the lamp to ground. So if the wire from the light to the switch is chafed and makes contact to the frame you might get a false indication. Vibration from the revving engine or even the movement of the throttle cable might break that contact and give you the wrong idea that it's really an oil pressure issue.

sledge · June 19, 2006, 03:00:58 AM

After reading the comments I would be taking the bike back to the people who did the work. Obviously something has not been done correctly.

calispec · June 19, 2006, 07:41:59 AM

ok, the more i think and look into this the less sense it makes. Jake D had been having the problem for a while, here are a couple posts he had about the problem

http://gstwins.com/gsboard/index.php?topic=14298.0

http://gstwins.com/gsboard/index.php?topic=16250.0

and

http://gstwins.com/gsboard/index.php?topic=25437.0

the wierd part is between the first two topics he'd had the motor torn down and rebuilt with new rods, pistons, rings, etc, and the same problem still kept happening. And between the second and third he'd replaced the oil pump and the problem still persists.

WTF mate!?!?!

Kasumi · June 19, 2006, 07:45:37 AM

Well electrics, and piping then would be the thing i would check.

calispec · June 19, 2006, 09:31:33 AM

Quote from: Kasumi on June 19, 2006, 07:45:37 AM
Well electrics, and piping then would be the thing i would check.

what do you mean specifically? What piping?

Mandres · June 19, 2006, 10:52:37 AM

I agree that the next step is to hook up a gauge and test the pressure. That way you know whether you really have an oil delivery problem or if the switch/light is just malfunctioning.

-M

Kasumi · June 19, 2006, 11:09:54 AM

Well there must be tubing from the oil pump to the engine to the cooler or whatever to let the oil flow. The other thing would be to check the electrics of the oil pump and the oil pressure sensor.

MarkusN · June 19, 2006, 11:41:36 AM

Actually, as far as I know, it's all drilled holes and ducts in the carter, and the pump is driven mechanically.

rangerbrown · June 19, 2006, 12:50:00 PM

well, i hate to say this, reading all of his post i found these few things.

befor the work was done,

lots of smoke, rings toast, most likey engine bearings worn out of spec.

rebuild, only left side done, to the tune of 1700$ WTF i could have goten 3 used engines off ebay for that price.

still low oil pressure befor and after.

oil pump replaced, then after a while the light cam back on.

the regulator was never replaced, ( I feal that this was the problem to start with, and it is now too late to do any thing.)

he only put 50 miles on the rebuilt engine so he said, a engine need at least 500 miles to be broken in right.

the new owner said he found metal in the pan, there should be none. if the shop did the job then i am sure they would have flushed the parts befor the install ect... now thasts not to say there should be some but it should be berrly visable. it at all AT 500 MILES. that would give it time to get a little on the pan.

I am going to tell you the truth, and sad sad truth, take as you wish. the engine is toast. there is a major problem with, not just the oil.

got to a junk yard and get another one that runs or ebay. i have seen them for as low as 400$.

if you dont think i am right then just drop the engine and pull all the covers off it and see were the metal is coming from. post pictures i can help you better, i work on engines and have rebuilt several air cooled engines

the thing that kills them is no oil, its there only way to cool other than air.

calispec · June 19, 2006, 02:47:05 PM

i guess i don't follow a couple things here:

1) why, if the the oil regultor was the problem, is it too late now?

2) if you are saying the bearings are gone, and i think that is what you are getting at, wouldn't there be an indication beyond the oil light? I spun a bearing in my car about a year ago, and i had about 500 miles of gentle (though growing louder) ticking to let me know it was coming to prepare and get parts for the rebuild. And at no point up untill i spun it did my oil light ever move. Apart from the oil pressure light flicking on at idle after about 30-40 minutes of running the engine is great, no ticking, pulls and purrs great, the oil light just flicks on.

3) Other than the dust in the oil which may or may not be expected following a rebuild what are the indications that there is something sinster at work here?

Thanks everyone for your time and explainations

GeeP · June 19, 2006, 05:43:41 PM

Oh boy, here we go. The bike is dead, the engine is toast! Let's all wear black and bury the poor thing because it's damned to never run again. I'll bring the booze.

Actually, let's get systematic.

1) Why is there crap in the oil? Are there chunks? How many? What do the sludge holes in the base of the oil filter housing look like? If they aren't spotless then the machine shop didn't clean up after themselves. That could explain the "chunks". Are the chunks magnetic? Let's see photos of the chunks! What does the oil filter look like?

2) What does the oil pressure read NOW? Jake D says that he had 22 PSI at 2000 RPM before replacing the oil pump. After replacing the pump the oil pressure presumably went up. Now it's back down. Why? The GS does not have a pressure relief valve in the oil pump, therefore there is no excess capacity available at idle. That means the bearings are too big, there's a severe gasket leak, or the pump is bad.

You're never going to figure it out and we can't help you figure it out unless you start knocking these problems down. We need a baseline. What do we have on the spacecraft that's good?

I've maintained / modified / overhauled / repaired engines from 2HP to 200,000HP since I was 5. In that time I have seen only a handful of engines that had to be scrapped. Most hit the ground in excess of 500MPH. The rest were in lots of little pieces, or a few big pieces.

You have oil pressure. THAT'S GOOD! It's very likely that your engine has not been damaged. I suspect that you have an oil pump problem, possibly due to a faulty mounting gasket. Another possibility is that the main bearings were sized too big.

Let's start checking off possibilities!

calispec · June 19, 2006, 08:12:16 PM

i'lll let you know what my oil pressure reading is as soon as i can. Rght now my bike is my parents garage in a different town and i go visit it on the weekends, so i try to do all my question asking now so i can do all my wrenching then.

The chunks I saw in my oil turned out to be littler pieces of gasket sealer and imperfection in the bottom of the oil pan (tiny metal mountians) not actually chunks of metal deslodged from the engine. I just saw these things and freaked out initially. The "sludge holes" did have some of the same metal dust in them that i found among the fins in the bottom of the oil pan. Unfortunately i don't have pics. I did pull the old oil filter apart and there were teeny tiny speck of metal barely larger than the dust in the creases but nothing remarkable.

This is really all i know untill i can get a pressure gauge hooked up but no one seems to know what is needed to do that exactly. What is the size of the hole, what if any fitting are needed, so i guess i'll just have to fake it. If anyone knows what it take to do that, please let me know.

calispec · June 21, 2006, 07:36:44 AM

easy question this time,

1) (the easy one first) is there oil setting behind the oil pressure sensor with the engine off? I know i have to pull this to hook up an oil gauge, but when i do that is oil going to come rushing out at me??

GeeP · June 21, 2006, 11:11:57 PM

There will be some, but it shouldn't drain the whole sump out. Have the fitting you intend to install handy and switch them out quickly.

News:

another odd oil pressure issue