Clogged Oil passageway??

[TheNose]

I took my camshaft cover off and noticed that all the cam lobes are sitting in a pool of oil except for the intake on number two cylinder. Does anyone know how the oil flows to each lobe? I looked for an oil passageway, but can't find one. Please help.

Terry

[TheNose]

Is it possible that the oil comes up under the cap that holds the camshaft down? I can turn the engine over with the starter motor, and oil flows to the other cams, but not this one. I don't want to put it back together until I find the problem. Has anyone had any experience working on a eight valve GS engine that might be able to give me a clue? Any guesses?

Terry

[saaz]

I will post some details whe I get home. My factory manual has a diagram of the oil paths. The cams don't need a high pressure oil supply, just enough oil volume going up the top end before it falls back to the sump. The GS oil system is high volume/low pressure. It is normal for oil pooling around some of the valve buckets (unless it goes down your valve guides!!)

[TheNose]

Thanks, saaz. I can see the oil is coming in and pooling around all the other cam lobes. This one, the intake on #2, stays empty.

On the others, it appears that the oil is coming up from around the tappets, but I can't tell for sure. I'm thinking about pulling the cam shaft out and lifting the tappet to see if there is a hole inside there for the oil to come out of. I'd rather not do that unless I have to though.

Terry

[Anonymous]

The oil is supplied via the cam bearings, i.e. under the cam cap as you guessed. You should have oil coming out of all 4 cam bearings and pooling in all the valve pockets.
If you have no oil supply to the cam bearings, the bearing will nip up in not time flat, usually less than 5 miles riding.(I know, its happened to me.)
Don't expect too much oil flow, but you should get some to all 4 cam bearings.

The full path is up the rear cylinder head studs and into drillings in the head which you can see the plugged ends of, then to the cam bearings. Can't remember if there is also a supply to the buckets or whether oil just drains into the pockets.

Like you, I'd want to see oil coming out before I continued.

[TheNose]

Thanks, Brit. I am very anxious to ride again. Today is a holiday in the US and I'd rather be riding. I do question as to how the oil gets into the pockets. I don't see any holes in them. Could it be possible that the oil comes in under the tappets and then is "pumped" up by the cam action? Or, does it just seep from around the cam shaft and into the pocket?

Terry

[Anonymous]

I think the latter.

[TheNose]

Ok, Brit, you solved it. I took the cam shaft out and the hole for the oil is under the cap. I took an air hose and blew through the hole, air came out the other hole for the #1 intake cam. I then squirted new oil in the hole and blew it out again. I re-installed the cam shaft and spun the engine (no spark plugs) and oil came out from under the cap ad ran down the side of the wall. Success, oil flow again.

There was minor scouring under the cap on the engine side of the cradle that holds the cam. I don't think it was bad enough to cause further damage to the camshaft. I think I caught it just in time.

Thanks to both of you, Brit and saaz! It took an multi-national effort, but I think we saved my bike.

Terry

[Anonymous]

Sorted!

Score one for the good guys.

[Anonymous]

Sorted!

Score one for the good guys.

I am guessing that you are saying that the problem and details are sorted out--SEEEE i can learn to speak english(((a bit ))

[earlfor]

What is puzzling me is I perceive the engine had no damage (broken bits, skirts, metal pieces) in the oil, was used with a working oil filter and the oil was changed with a normal frequency and hence was normally clean. What would be the reason for blocked oil passages? I dont see why that should happen, so I must be missing something here.

Earl

Ok, Brit, you solved it. I took the cam shaft out and the hole for the oil is under the cap.

Thanks to both of you, Brit and saaz! It took an multi-national effort, but I think we saved my bike.

Terry

[TheNose]

What is puzzling me is I perceive the engine had no damage (broken bits, skirts, metal pieces) in the oil, was used with a working oil filter and the oil was changed with a normal frequency and hence was normally clean. What would be the reason for blocked oil passages? I dont see why that should happen, so I must be missing something here.

Earl

Ok, Brit, you solved it. I took the cam shaft out and the hole for the oil is under the cap.

Thanks to both of you, Brit and saaz! It took an multi-national effort, but I think we saved my bike.

Terry

I wish I knew the answer Earl. I think I may just have been lucky to catch it when I did. My original intentions were to check the valve clearances and I happened to notice that there was no oil pooling around one of the cams. I have only had this bike since June 2002 and I think the previous owner was a mechanical retard. I changed the oil when I got it, but don't know what frequency, if any, the previous owner used. If the GS's weren't bullet proof, this bike might not have survived him. I have repaired almost every major component on the bike. I think all he did was ride it. It's in good hands now. My first bike and I love working on it and riding it. More so riding, but if it breaks, now I know how to fix it thanks to all the people on this board.

Terry

[saaz]

I have not been home yet..so will post something tonight! I will check for any other oil passages.

From memory the cam cap holes are a bit smaller to supply a little bit of pressure to the plain beraing of the cams. If someone has been careless a bit of rubber sealant, gasket etc may drop into the oil while doing the valves. It sounds like another early oil change may be a good idea to get anything else out that may be in the oil

We also speak a bit of English downunder, mates!

[Anonymous]

We also speak a bit of English downunder, mates!

Thats funny, cos we're all learning Oz up here! What with "Neighbours" and "Home and Away". My kids are all totally "rapt" by them.

Not to mention Fred Gassit in the bike mags. Pulled any horn mono's recently? My favourite phrase is " Get a big black dog up ya!"

[saaz]

Gassit is a legend, not at all politically correct.

Anyway, oil passages. My factory manual for a 78 GS1000 indicates that the top end is oiled as follows:

under pressure to the camshaft journal., then
splashes out to the cam face, then
splashes out to the tappets, then
splshes onto the camchain, then
falls into the oil pan to start all over

The factory manual has a few good diagrams of the engine and lubrucation syste. I should scan then oneday to put on the site under the tech section