Evo rocker cover sealing

[hardtail84]

I just regascketed my old evo because it was leaking pretty good around the rocker covers and lifter blocks, etc. The first time I put aviation formagascket on the rubber seal. When I snugged them down, the center spacers slid right out to sides. Seeing that wouldn't work I took it back apart and cleaned the gasckets and surfaces with laquer thinner. I reinstalled them dry, lining everything up perfectly. All looked good. I started the bike and warmed it up completely in the driveway, it was around thirty degrees here. No leaks ,all good. I put the bike back in the garage and was admiring it when I noticed the center spacers were not lined up evenly anymore. They were both shifted a little to the left, W.T.H. Nothing is leaking but do you think they will move some more when I start riding the bike? Is this movement normal? Thanks for any info, Mike.

[ceduby]

My rule of thumb is nothing on rubber gaskets. Anything that will make them slippery, they will move once you start torqueing. They need to be clean and dry as well as the surface.  I suspect sooner or later it will start to leak.

[hardtail84]

I did clean and install them dry. They still moved a little, that's what concerns me.

[dave_9113]

You using Harley rocker gasket?  My middle one didn't fit right either and my rocker covers weren't warped, but I pinched it at the higher end (slope) of the rocker box to ensure less chance of leak.  Once torqued down properly, they worked OK.  You should heat cycle the engine a few more times and let them settle.  Easy enough fix if they do leak though.  And definitely no dressing on rubber gaskets. 

dave

[ceduby]

It seems to me that once anything gets on the rubber gaskets, pressure applied as in torquing, then removed to correct an issue,(especially since engine heat has been applied) they're not the same. It's a coin toss weather they'll leak or not, but if it has moved like you said, the odds are not in your favor. Being as it's winter and sounds like it's cold where you are, I think, (and have in the past) just bite the bullet and install new gaskets and call it lesson learned.

FYI, I installed new rocker cover gaskets, dry and clean, after about 200 miles or so I pulled the covers again, ( I was chasing a noise ), The gaskets had swelled just a bit, so I cleaned them and the surface, the gaskets didn't seem to fit very well anymore so I put them in the freezer hopeing to freeze them back down to size. The seals swell once in contact with oil.  Well it sort of worked, one set sealed up with no leaks, but I ended up with just a small leak on the other. It wasn't a bad leak so and the season was just about over so I just ran with it and wiped it off after each ride. When I pulled apart over this winter, I saw where I pinched a spot and that was where the leak was.

So from then/now on, the gaskets/seals get replaced  no matter how much or little time is on them. It's not worth the aggrevation, especially if it's nice riding day, to take it apart again.

[hardtail84]

Ya I suppose you're right about them not being the same after being installed then removed and flattened again, although they were not heat cycled as I removed them as soon as they slid around when I tightened them. I was just wondering if this movement is something that happens now and then or if it's going to cause a problem. I supose I'll have to do it again. "Potty mouth".

[fxr4mikey]

bummer .... but better to do it now, take your medicine and then enjoy the riding season when it gets here ... ya don't really wanna be messing around with an oil leak when the good weather gets there .... now do ya .

[dpb-RK]

I tried twice a few years ago to get those rubber jobbies to seal.  I found that once the correct torque is acheived the two surfaces touch in the corners, because those surfaces are not machined flat the corner 'high spots' slip to the side once the engine starts to fire (vibrate).

My solution, right or wrong, was to put the torque wrench back in it's box and 'eyeball' the join. I tightened down till there was a very thin black line all around the joins. Since then I have had no leaks ( wish I hadn't said that ). It seemed to me that the torque figure was so low that an even joint would be better than a 'technically correct' joint and it has been 

[tinkerman]

Right on dpb,

A little injection of common sense overcomes blind engineering. I have always believed that a little bit of intuition and experience can improve upon some shop manual methods....shoip manual is still a must......just not the be all end all for every process.

Tink

[rdkng]

I've had them move and not leak on both new gaskets and reused ones.
When I tighten them down in small increments and following the torque
pattern many times, they seem to move less and seal fine.
I also think the HD 'rubbers' are the best.
rdkng 

[hardtail84]

That is what I wanted to hear. I've been wrenching for 45 years on everything under the sun, but this old boy is my first evo. I have a twin cam hot rod bagger that I have built up in the normal Hippo fashion but I don't mind having a little guidance on unfamiliar teritory. I guess I'll ride it and see what happens. Thanks a million for all the responces.

[JohnS_Rosamond]

I breezed through the responses for forgive me if I repeat what someone else already said.  If you were very careful putting the tiers back together again and they moved that quickly, I'd suggest that you have a tier that's warped pretty bad.  I had this happen to me on the rear cylinder of my Evo.  It would stay put for a while, but eventually would move so far over that oil would shoot out of the now-unaligned rockers.  I tried a bunch of stuff, but eventually I replaced all three tiers.  No more problem.  The front rocker never did it to me.

[hardtail84]

I was thinking about warpage too. What I don't get is why didn't they put some alignment lugs around the edges of the bottom tier. Oh well...