Cam cover oil leak - newbie

[xrdv8]

Hey guys (and gals I'd guess),

I'm a CBX newbie who just bought a '79 with 25k miles on it. Nice overall condition. When I bought it the seller said the cam cover weeped a bit. Well more like a steady stream of oil that finds its way to your legs making it no fun to ride....

So I read in the forum that the first step is to replace the little chrome cam cover bolt seals with new ones. I did that today. As i loosened the cover bolts the cover would "pop" as if it were torqued down wrong initially or not seated properly previously. Before I finally removed the cover I noticed that little arm that goes between the front and rear cover had cracked right at the back of the front cover. The cover did not really want to come off but I persuaded it to.....

So I eagerly started it up and it leaked. I tightened up the bolts a little tighter until they bottomed but it still leaks from from the front corners. The larger cam cover seal still looked soft and pliable to me so i did not replace that initially.

My question is (if you have read this far) if should I just replace the larger seal now or have you guys seen the cam covers warp and I need to replace the cover itself? I put on the smaller cam cover end caps after i put on the new bolt seals if that matters.

Last note is that the bike may have been down on the right side as the fins appear to have been ground down a bit and perhaps tweaked the cam cover???...

All help appreciated!!

Maury

Several vintage motocross, street and flattrack bikes
H2
Norton 850
Triumph Hurricane
etc...

[bobber01]

If the gasket is in good shape remove it and clean up any residual adhesive from both it and the cover recess where the gasket resides into. Apply some sealant in the cover recess and on the head, particularly at the corners and where the recess are at the end. Don't be offended by this next question, I've done worse LOL. Are the valve cover bolts placed in proper location? The (4) four longer in the center and (4) four shorter bolts on the ends.
Can you place the cover on a relatively flat surface to check for any warpage?
Bob

[Jeff Bennetts]

And since your a noobie I'm going to say it even if you already know, do not over tighten the bolts or you will bust a cam holder.

I clean the cover completely where the gasket sits, use a small brush and apply 3M weatherstripping cement to the gasket and cover then put the gasket on and press it in and make sure it's seated.

Then clean the head sealing surface and appy Holymor gasket sealer on the head and wipe off any excess that may get on the inside of the heads lip, torque it down.

The great thing about Holymor is it won't harden and the cam cover will come off the next time you need in there.

[NobleHops]

Yes, be very careful about which bolts go where, you can get into Big Pain if you mix them up. Also, those bolts are shouldered. They are only tightened till they are snug, you dare not try to seal it by tightening it more, you will only snap expensive things in the cylinder head if you do. When I thrashed with this the culprit was an old shriveled gasket - see my photo below with old and new. Also, there are two styles of sealing gaskets for those bolts - smaller thinner ones that work with the 79, and larger thicker ones for teh 80, 81, and 82. That's another gotcha that gotme.

Once you verify that the cover is flat, clean that channel within an inch of its life, smear some threebond in it and set the gasket. Put a pea-sized dab of three bond at the corners where the cam end caps are - the round end bits on the gasket that have a nearly 90-degree bend. Then put the correct bolts in the correct spots and only tighten till they are snug, and no more. If it leaks after that, your problem is elsewhere.

Also - remove the tach drive when you do this. Breaking that is also expensive and painful.

You really really need the FSM.

Welcome, by the way!

The two styles of cover grommets:


Old v new gasket:


Swapping the grommets for new using sockets as anvil/hammer:





N.

[xrdv8]

Thanks so far guys.

Yea the bolts are in the correct order. They were only tightened until then bottomed out.

I'll check the warpage and also clean out the sealing surface and apply some sealant - and try it again!

Just to be sure I'll put the smaller cam covers on first on the next go around!

thanks again - maury

[steve murdoch icoa #5322]

I hope i have gotten lucky with the valve cover leak on my '79.
Thinking i had a couple stripped threads i took the cover off today, chased the threads and they all seemed secure with minimal debris. The threads on the bolts were also undamaged but i did notice two different size rubbers on the bolts.
The four longer bolts on the inside spots appear to have the shorter, squater rubbers from the later years?

[Goss]

Welcome,

I use sliver Hondabond and make sure that the head and cam cover to gasket surfaces (and gasket) are clean by wiping over with a slovent just prior to painting on the Hondabond. I then fix the gasket to the camcover then place it on the head. It does not really matter which sealant you use as long as it is flexible and remember that cleaning it off the next time you remove the cover is a consideration, personal taste I guess. The key is not to put too much on as you do not want any surplus circulating in your engine! Once secured I leave the bike overnight so everything cures and start it up the following morning, to date only had minor issues with the seals on the cam cover but never had drips.

Good luck.

Regards

Goss

[steve murdoch icoa #5322]

Just a little follow-up on the rubber grommets.
My local Honda shop wants $8.95 each and they are back ordered with no availability date. Add tax and $10.00 in gas to drive to the shop and i am at around $92.00.
Delivered to my door from Bob at Performanceintl it will total out at $19.00.
Granted K&L brand versus OEM...i am willing to take the chance on aftermarket.

[xrdv8]

new gasket ordered - I used the K&L grommets as well - they seemed to work fine - the leak was around the edges!

[1979cbxman]

Hi! Another newbie here. I hope that I'm not hi-jacking your thread here. You guys talk about changing out those cover gaskets and seals like they're easy to do. Are they that easy with the engine bolted into the bike or are you guys working on uninstalled engines? The reason I ask is because I tried to change the 8 original cover bolt seals on my '79 with the engine in the bike last week and it was a tough job and I didn't get it all done. I only managed to get the inner 4 changed as the outer 4 bolts wouldn't come out of the cover. The factory service manual doesn't say anything about these 4 outer bolts having clips on them or something like that. I pryed on them to the point I was afraid that I was going to do damage so I stopped. I can't imagine removing the valve cover with the engine in the bike. Too much stuff in the way! Can it be done? I'd like to replace the gasket myself without having to drop the engine out of the bike. Help?

[EMS]

It will definitely be easier to remove the valve cover when the engine is tilted. It is probably possible to do this with the engine in the fully installed position, but I have never done that.
Make sure, you remove the tachometer drive, before you attempt to remove the cover, otherwise you will break the cam cap.
The bolts should come out of the cover relatively easy. You may have to fight the fact that they were never out before and that they enjoy the position they had for the last 30 years too much.

[spencer]

You can replace the gasket without removing the engine, but you do have to tilt it forward. You really should have a shop manual. The procedure for tilting the engine is in the shop manual. Follow the instructions, including removing the tach drive, as suggested by EMS above.

[1979cbxman]

Thanks all. I guess I'm going to pay the pros to do the job as I'm just not set up for it. I'll keep you posted!

[spencer]

You can replace the gasket without removing the engine, but you do have to tilt it forward. You really should have a shop manual. The procedure for tilting the engine is in the shop manual. Follow the instructions, including removing the tach drive, as suggested by EMS above.

Just to correct myself, you can remove the valve cover without tilting the engine. It is pretty tight, but you can do it. If the engine is tilted, it is a lot easier. I was confusing the valve cover removal with carburetor removal. You only need to remove the engine brackets to the top of the engine in order to be able to get the valve cover off. But do remember to remove the tach drive first. Sorry if I gave some bad advice above.

[Rick Pope]

Spencer is correct. You can slip the cover out with the engine still in it's mounts, except the large front mount.

The cover gasket works fine with no sealants at all. In fact, I believe that's the way the "Factory trained" guys do it (Mike Nixon?). I've done it, but it's a heck of a lot easier to use a tiny bit of some type adhesive in the corners, to hold the gasket to the cover while you install it.