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XR 400 valve cover leak

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Just got my XR 400 back from the shop, after a top end rebuild.  Bikes runs great, but the joint between the new head and the vale cover is leaking.   If I pull the valve cover off, to clean, seal and reinstall, will i have to re adjust my valves.  The rocker arms are mounted to the underside of the cover? The mechanic said it should not be a issue, but i am a little unsure.  I believe there is no gasket for this joint, you just apply some "gasket maker" to it.    I would just load it up and take it back to the mechanic to fix, but that might be more trouble then its worth, as long as I don't screw up the valve settings or have to re adjust them, it will be easier/ faster to do my self.    Any tips on getting the joint to seal the first time.

 

thanks

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It came from the factory with a gasket.   They are generally reuseable, metal,  and about 35.00 each.   One of the few ones I reuse,  and use some non hardening sealant on.  Your valves probably won't need to be reset, but those are the simplest ones in the entire industry to adjust.  Something you should learn to do at the very least.  if they left out that gasket,  you are certainly going to need to readjust them.  Your "shouldn't be an issue" mechanic scares me,  btw.

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Double check all the 8mm head bolts are torqued down properly..the valve lash shouldn't be affected if you have to pull the cover but check them with a feeler gauge if you're worried when you put it back on.  If I remember right it's a metal gasket 

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It is metal. And reusable for ten years if properly torqued.
So was it properly torqued? A question for the mechanic that should be fixing it by putting in a brand new gasket and re torquing to be sure.
But the quick way to do it, is take it off, put all bolts in a can of gasoline, clean everything. And squigee Hondabond to coat both sides of the gasket. Put cover on. Dip the bolts into motor oil. Install.
Torque specs
Ive been doing 17 ft lbs.
If you didnt even tighten the bolts and the gasket had hondabond, it still wouldnt leak! But a metal gasket...one bolt not tightened, it will leak.
Your leak is probably that. One bolt not tightened or not torqued. And no silicone. Dont trip. Just dont drip all out and run dry

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As has been said, there IS a gasket that is supposed to be in that position. The head cover also functions as the top clamping surfaces for the cam. Those clearances can be improper when the cover is installed without the proper gasket.

Here's a good video series for working on the XR400 engine. Parts 1 and 3 show removal and install of the head cover.

 

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hummm,  i will have to look into this, he told me that they did not come with a gasket, now i am going to be pissed if he screwed that up.  I have never heard or had a bad experience with this guy or his shop.  Thanks for the input.  I will double check the bolt torque as a first  step.

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IMG_3495.PNGGASKET, HEAD COVER
12391-KCY-671 $25.52
If its not BENT or comPLETEly flattened. You can use this gasket for ten years, espECially with a film of Honda bond.
And start cleaning all your bolts in a cup of gas, take them out with a magnet stick, and cover them with oil before install, and USE TORQUE SPECS.
20ft lbs.
I do 17 all day, erry day, for more than ten years
But buy a new gasket

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