No oil in one cam shim bucket - 82 gs850g

[dtgordon]

I hope someone has heard of this and can help. Bike is an '82 gs850g. Had cam cover off and noticed number 2 intake cam shim bucket is nearly dry, all 7 others had a good ammount of oil (nice and wet which is good). Why is this one dryer (almost no oil) than the rest? Suspected a clogged oil passage. Removed cam caps and intake cam. Inspected oil port (hole) in bottom of cam journal, it's clean, could see through it, no sign of sludge at least from this view. Re-installed and re-tourqed bolts. No change. Next, cleaned oil pan and oil pan screen. No sign of sludge in screen. Somewhat surprised at how clean it was (previous owner must have kept it clean). Next, checked oil pressure with guage. Pressure is within spec. ran about 3.5 PSI at 3K RPM. Ran about 5 PSI when above 6 K RPM. Book says anything over 1.6 PSI (I think) at 3K RPM is OK. Next, flushed engine twice using Gunk engine cleaner (thinking sludge might be a problem), and changed oil and filter, and now driving for a while to see if it helped. BTW, all cam shims are within spec. Is it possible the cam cap is a bit too tight around the camshaft and doesn't let enough oil to slip through and flow into the shim bucket? Should I install a super- thin gasket (like .001 -.002") between the cam cap and head to give a little more clearance for the camshaft, which could allow the oil to pass through a little more easily, or is this a bad idea? I'm thinking a small gasket would essentially work as a "shim" if you will. Also, one other telltale sign of this dry bucket is that around 4000 RPM i get a distinctive "buzz" which I believe is the sound of the shim and cam slapping together with the approximately .002" clearance (almost sounds like a bee buzzing). I've eliminated this sound temporarily by pouring oil into the bucket (while cam cover off, of course) and driving for a bit. It sounds nice and smoothe, but eventually the oil splashes out and I have this dry condition once again. Has anyone heard of this? Has anyone solved it? What about my gasket/shim idea? Thank you for your help!!

[rapidray]

Please tell me that before you removed & re-installed the intake cam, you removed the cam chain tensioner first? Ray.

[dtgordon]

Yes, for sure Ray. And then correctly retensioned after re-install. Although I'm fairly new at this, I do have a factory service manual, a Haynes and a Clymer and I usually consult all 3 before turning a wrench. Any idea on my particular problem?

[chef1366]

Any heat stress or marking on that cam lobe to lead you to think that it's oil starved? If you weren't getting oil there you'd know right away.
If you don't mind a bit of a mess start the bike with the valve cover off and see if you have oil flow there.

[dtgordon]

There appears to be a little heat stress. slightly darker color compared to rest. The way I know it's starved is after a ride, I get off the bike, put it on center stand so no oil remaining in the buckets will spill out, let it cool, open the cover and right away can see the bucket is dry while the others are wet. Also, as I mentioned in original post, the buzzing (metal on metal) sound at 4K RPM is a telltale sign. Read below how I proved that.

[chef1366]

Isn't there an oil journal in the cam bearings for it to flow? This should suffice for the oil flow.
If you're sure the oil ports are clear this is surely weird with the oil volume being up to par.
I would try racing oil pump gears and a new pump.

[BassCliff]

Greetings and Salutations!

Hi Mr. dtgordon,

Hopefully I won't make anybody mad at suggesting this; Some members of this forum have used Sea Foam in their crankcase oil to help clear passages and clean out sludge. Use the recommended amount (maybe even a little more) in a new batch of engine oil and ride for 50 to 100 miles or so. Then change the oil and filter again. Don't leave it in your motor for any length of time. Drain the oil while it's hot, or as hot as you can work with it. Hot oil will carry out more gunky stuff. (Forgive me if I state the obvious.)

Now let me roll out the welcome mat for you...

Please click here for your mega-welcome, chock full of tips, suggestions, links to vendors, and other information. Then feel free to visit my little BikeCliff website where I've been collecting the wisdom of this generous community. Don't forget, we like pictures! Not you, your bike!

Thanks for joining us. Keep us informed.

Thank you for your indulgence,

BassCliff

[Nessism]

I've noticed that my '82 850 also has at least one valve pocket that is dry when the valve cover is pulled. Have to admit that I haven't given this matter a whole lot of thought though.

Good thing is that the valve train is one of the strong suits for the 8v engines; it doesn't take a whole lot of oil to meet the engines needs.

Question: did you check the cam journal clearance when you pulled the cams?

[dtgordon]

Thanks Ray, Chef, BassCliff, and ed for the quick replies. This is really good stuff here!

I'll answer Chef: your question, isn't there an oil journal in the cam bearings? Yes there is. The hole is on the bottom side. The camashaft appears wet with oil, but not enough to spill the exces into the bucket. Hence my concern. Thanks for the pump gear suggestion.

BassCliff, I'll consider the Ssea Foam idea.

Ed, I like your question. I did not measure the cam journal clearance. Maybe we're on to something. Excuse my ignornace. How should I measure my cam journal clearance? I have a caliper, but not a mic. Do I need a mic? Is it possible the clearance is too tight, thus restricting flow out of the cam journal and into the pocket (or bucket, if you will)?

Dave

[Nessism]

The service manual details how to use plastigauge to check the journal clearance. Cheap and reliable way to check.

[Big T]

Also, as I mentioned in original post, the buzzing (metal on metal) sound at 4K RPM is a telltale sign. Read below how I proved that.

A buzz at 4K is often the horn mounts moving in sympathetic vibration. You can check this by looking at them while you rev the motor.

[propflux01]

I fail to understand how cam clearance would suddenly be an issue. I mean, how would it suddenly get smaller?

[Dave8338]

I fail to understand how cam clearance would suddenly be an issue. I mean, how would it suddenly get smaller?

They don't get smaller over time, they increase. The increase causes lower oil pressure in the cam bearing and thus allows for a greater chance of a "hot spot" as a result. Plastigauge works VERY well and is as good as you need on most any engine.

[tkent02]

They don't get smaller over time, they increase. The increase causes lower oil pressure in the cam bearing and thus allows for a greater chance of a "hot spot" as a result. Plastigauge works VERY well and is as good as you need on most any engine.

Unless someone swapped cam caps from another engine.

[Dave8338]

Unless someone swapped cam caps from another engine.

GOOD POINT!

Should always be done as a set (head and cams) IMHO...