Oil collecting around cylinder head bolt

Bike: 1982 XJ650 YICS

I just recently did a full top end rebuild, piston rings, valves, base and head gaskets replaced, carbs cleaned and rebuilt etc. While breaking in the motor I noticed steady oil collection on the 10mm bolts on the front of the motor and on the left hand side fins. Upon further inspection I found oil pooling around the cylinder acorn bolt on the 3rd in on the intake side (bolt #1 in the tightening sequence and #11 in the loosening sequence). I believe that this is also connected to oily fins on the front and the bolts and is possible traveling down the rod and out the front via the drain gunnels. The valve cover gasket was replaced 2 years ago.

Could this be anything other than a bad valve cover gasket? Could it be indicative of a poorly seated/failing head gasket or base gasket? Could the oil be forced up under the washer and bolt or is it only possible it is dripping down on top of it? Is it possible to buy new crush washers that go under the cylinder head acorn nuts?

thanks ARI

 

Did you replace the o-rings, crush washers, and special seals for the oil supply and return to the head?

Were the rubber dougnhuts for the valve cover bolts replaced when you replaced the valve cover gasket?

Has the engine gone through enough heat cycles to warrant re-torquing the head nuts? That should be done at least once after having the top-end apart.

 

Thank you for replying.

No to all of that! I replaced the cylinder jug O rings but I re-used the 2 rubber components in the oil supply chambers/tunnels of the motor. Is it odd that oil is on an inside bolt and the oil supply gunnels are on the outside of the motor? I will order new doughnuts and crush washers post-haste.

 

Is there a diagram showing the oilways throughout the XJ engines available thanks?

 

You made the same mistake I did regadring the special gaskets.

If those gaskets aren't sealing the oil will find its way all aroud the head gasket, and can show up anywhere.

 

The service manuals have that info. There is some variation depending on which engine you're looking at. I don't think the diagrams have been uploaded here, at least not for quite some time.

 

What do the crush washers do in engineering terms k-moe ? I have a lot to learn yet. Are they the copper washers on the right of the cylinder head? If so they surely are relevant to the oil feed to the cams? The oil feed is on the right side of the head because below and above the cylinders there are O rings around the cylinder studs ie the special seals you refer to I think. Are the O rings you refer to the YICS ones. I am still learning about these engines hence the questions thanks. You know a lot more than I do about engines k-moe.

 

I had one for an old Volvo car I owned I just like to see the oil flows through the engine schematics.

 

The crush washers are solid copper, and seal the oil galleries to the cams. They are used under the far right head nuts instead of the standard steel washers.
The o-rings I'm refering to are for the base of the cylinder block. The special o-rings/seals are used between the top of the cylinder block and the head.
That's all pretty standard for an internally oiled motorcycle engine (no external oil lines).

The YICS o-rings are located to the rear of the head and cylinder block, and never touch oil.
YIKES!: ALL ABOUT THE "YICS" SYSTEM.

 

So the YICS O rings if they fail would cause a vacuum leak albeit between the head and cylinder block.

 

Correct. I have never heard of a case of them failing though.
They are surrounded by the head gasket (there are individual cutouts in the head gasket for each YICS port), so even if they did fail a vacuum leak would be unlikely, and probably quite small.

 

What an engineer would call unintended backup or redundancy.

 

I looked online and couldn't find crush washers or the special o-rings/seals that go between the top of the cylinder block and the head. Is this something available through the XJ online store?

 

Yes, and that's about the only place you'll find them, My local Yamaha dealer couldn't get them.
Start a conversation with @chacal

 

Interesting the YICS what Yamaha called controlled turbulence an oxymoron like Dream Theater's title Systematic Chaos. Did Suzuki's TSCC use the same swirl methods of achieving efficient combustion?

 

One actually can control turbulance to a degree. The tornadoes made in atmospheric labs being one example. While the internal structure is not under (direct) control, the overall event is.

TSCC used features internal to the combustion chamber to achieve a similar effect.

 

Like the vortices round aircraft wing tips are drastically reduced by the small winglets although they are not enclosed like you refer to. It is all very intetesting.

 

Whats the protocol with replacing the gaskets and piston rings when I replace those oil seals...if the motor has been run for less than half an hour and never over 35 does all that still need to be fresh or could I get away with reusing the gaskets (in the very least)...thanks again K-moe for all your help.

 

If the gaskets come away cleanly you should be able to reuse them. I used the updated head gasket with the sticky ridge of sealant (integrated cam tunnel gasket), so had to get a new one, but I was able to reuse the base gasket. The rings and cylinders don't need to be reworked.