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Valve cover gasket an absolute necessity? Is it messed up for good?

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    Recently did a top end on a `99 XR4 and after putting everything back together I noticed a leak at the valve cover to head joint. I used Hondabond on that joint and thought I was possibly sloppy ,so took it apart again ,cleaned with acetone and reapplied the sealant making sure it was good  only to find out that it wasn't. 

     Took the head cover off again to find gouge marks in the cover like maybe the cam is keeping  the head cover from clamping tightly. The point of contact is at the midway point between the roller bearings. My guess is that I NEED an actual gasket on the cover and not just Hondabond to get the proper clearance. 

    My question to you guys is this. Am I correct or do I need to find another culprit and will having these gouges in the cover be detrimental to the cams clearances.? I guess what I mean is does the cam ride in that journal between the two ball bearings? Thanks in advance.

 

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Yes there should be a coated metal gasket between the heed and valve cover.

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Yes there should be a coated metal gasket between the heed and valve cover.

Yes I saw it on the micro fiche on BikeBandit. That is a pricey gasket for sure, but found a old stock one on E bay(OEM) for 25 at least. Wondering if after I get the gasket on my head cover that it is ruined because the tolerance may be to great.

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Here's the pic...Photo207.jpgclick on it. Does the cam need to ride in this area or are the bearings the only place it rides?

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I'd probably find a good used head cover, but you might be able to clean it up.

The center race is to constrain camshaft flex while the engine is running.

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I'd probably find a good used head cover, but you might be able to clean it up.

The center race is to constrain camshaft flex while the engine is running.

Thanks

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I bought a whole gasket set with seals and every gasket for my 1995 XR 250R for $40 on ebay.

 

If you have the old metal gasket if it is bent or even used previously then you can anneal it to give it the ductility it needs to seal all the way around when it is compressed.

 

I have a nasty leak from the gasket on my 650L because I bent it a bunch trying to get it on. Need to take it off and anneal it.

 

Heat it up with a torch or anything that gets it a reddish color. Let it quench in air (do not dump it in water) so it is as ductile as possible.

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That gasket needs to be exactly oem thickness.  If it's thinner, the rocker cover will clamp down on the bearings and bind the cam.  If it's thicker, the cam bearings will jump up and down with the cam.  I would not use anything other than an oem  steel gasket there.  No sealer is required and it can be re-used several times.  In fact, sealer with the oem gasket will cause the bearings to jump around in the journals.  Sealer has thickness.  Cheapskates and goopers have ruined a lot of motors.   

 

You're probably OK on your center journal.  The only thing I see happening there is if you have worn too much clearance, less oil will reach beyond that point to the left cam lobes.  That's not good. 

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X2 baha. Makes me wonder why the PO on my 650 got away with liquid gasket on the clutch side engine cover. Even those gaskets you have to keep in mind the oil pass which goes in to the oil filter. Too thick of a gasket and that joint could leak and you lose oil and pressure. Not sure where I would even use the liquid gasket stuff

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Center journal on the valve cover needs to be repaired or the valve cover replaced. XR's only will charge you about $175 to do the repair, or you can find oem replacement valve covers online (used or new)

I have a head for the XR250 that I am replacing, versus repairing. Need to buy the valve cover as well as both have decent galling.

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You can use plastigage to measure the clearance between the center journal and the cam.  Mine was .003" on the bottom and .006" on top after the previous owner installed a paper gasket.  He never got it running.  The paper gasket measured .007" and was binding the cam due to the pressure on the ball bearings.  I checked the cam at 4,000 miles and everything looks good.

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