Jota 180 cam cover

PeteK

PeteK

New member
Location
Milton Keynes
Hi,

Investigating an oil leak from the cam cover on my Jota 180 and it seems that the cover is warped.  If I hold a straight edge across the two short legs of the H it?s nice and flat, although if I do the same on the long legs, I can rock the straight edge. It looks like the rearmost leg is slightly twisted. This is also confirmed by fitting the cover with a new seal and I can get a 0.7mm feeler under the front corner of the rearmost leg. Needless to say, that?s where the leak is. It had previously been fitted with silicone, which I am doing again, but wonder if anyone has any ideas how I could straighten it or find someone?s to do for me.? Looking inside there? are some fairly heavy witness marks from the head studs, so I think these will be the cause. The head is all torqued down and has never been off as far as I know, so probably need to remove nuts one at a time and try to wind the studs in a bit if possible.
 
Sounds like the head studs have been put in the wrong way round if they are hitting the cam cover. The long thread goes in the crankcase first, owners often  fit them in reverse which sounds like what's happened with yours then the cam cover won't fit.
 
Look at what Alan mentions.
I should think that the cam cover is quite pliable and even if deformed, tightening it down should flatten it.
It may even have left the factory warped.

Paul
 
The warp doesn?t sound good. Apart from that, the cam cover is well known for leaks, especially when parked on sidestand.
Rather than silicone, I use a liberal coat of grease on both sides of the seal. I?ve seen blobs of silicone migrate through engines too many times...
 
If it was my cam cover I'd have a go at straightening it. 0.7mm isn't much of a bend so it would probably straighten OK without heating.

I'd scrounge a piece of thick steel plate that's nice and flat to use as a kind of gauge plate. Then I'd use clamps, shim material and/or wedges to massage the cover into shape. What could possibly go wrong?

Alternatively, swap your bent cover for the one that sitting on the gate post in Western Australia (https://www.laverdaforum.com/forum/index.php/topic,100495.0.html). His might be flatter than yours, and the gate post bloke isn't going to care whether his engine is oil tight or not.  :D
 
I can say that the gate post motor is assembled from past used by date components.
0.7 is fuck all. Would have thought  there would be enough flex to have it sitting flat once it's screwed down.
I wouldn't use silicone, that shit is for bathrooms not motors
 
Thanks for all the advice. I think I will order another new seal, then try to straighten the cover . We have a surface plate at work, so I can use that with sash clamps to try to ease it straight. I can then check the heights of the studs on the cam block to see if they are causing the issue and if so either screw them down more into the crank case or file off the top. I am pretty sure the studs will be the right way around as I know the two previous owners of the bike. Might stay with the silicon short term though if it holds, then investigate over winter
 
Just check in any stud or studs is (are) taller than the rest and if that bears any relation to where the cover is bent.
 
Check your cam cover screws are not too long (and/or the washers underneath the screw head are not missing). In such a case, the screw will bottom out in the cam bearing block and not apply force to seal the cover. You can also cause serious damage to the cam blocks that way.

HTH, Haggis
 
Fingers crossed, all good now. New seal sent super quick by Giovanni (thanks), spent some time measuring the studs through the cam blocks and all have ample clearance. Also checked fixing screws as per Haggis suggestion. Some were very close to bottoming out, so all reduced by around 1mm. Then my wife, suggested using the granite worktop in the kitchen to check for flatness and try to straighten if need be. Blimey, she gets ?wife of the week? award for that one! Anyway, able to manoeuvre by hand, so nice and flat now. Refitted to the bike and looks much more even. We?ll see tomorrow when I head off for the club meet. Thanks everyone for your help.
 
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