New Rocker Covers Saga

[plc]

Hi Guys,

Well I finally bit the bullet and bought two new rockers covers for my bike. Plain aluminium alloy ones with the standard shape. My old ones had been damaged by the PO and they had ground off the outside three fins, and then painted them all black. It always looked wrong.

So I get the new covers and bought a new centre stud for the RHS because that has an Allen bolt for some reason. Off comes the left cover no worries until I put on the new cap nut, tighten up and then turns and turns and turns. Off comes the cover, great the old stud has stripped the tread in the head. I figure I will address that after the right goes on.

I go to the right and take off the cover and then notice the centre bolt is going into a sleeve, and the bolt looks bigger than the M8 stud. So I now realise the left stud hole is stripped and the right one was stripped and repaired with a bigger thread. I try to put the cover on with the allen bolt, but the rocker cover hole is to small. Can't bring myself to scar the new covers, so I headed to the metalwork room and found an M10 threaded bar turned a composite M10/M8 stud  and tapped an M8 thread.

Then a mate helped me fit a helicoil in the left side so the stud would bite. Now in drilling out for the helicoil we went though, and now I wonder should I put silicon on the thread to stop any water seeping into that space?

Or do any of you guys loctite the stud in so the cap always comes off (not the whole stud) and the stud never turns on tightening?

Hope no one minds the lengthy intro.

Best to all,
Paul

[Rob Valdez 79 R65]

Those threads are notorious for stripping.  

I haven't looked at a head that close, but I have heard of some folks putting a thin nut on the backside, where the stud comes through.

Is there a high-temp silicone you can use in an application like this?  I would think the cyl. head temp would melt anything.

I finally gave up and quit using the center nut and stud.  My covers held on by the two small nuts on the ends.
No leaks.

It is called "pragmatism".

[montmil]

...Then a mate helped me fit a helicoil in the left side so the stud would bite. Now in drilling out for the helicoil we went though, and now I wonder should I put silicon on the thread to stop any water seeping into that space?

Or do any of you guys loctite the stud in so the cap always comes off (not the whole stud) and the stud never turns on tightening?...  Paul

Paul, If I'm understanding your question correctly, it would likely be OK to use some LocTite on the threads that anchor the stud to the cylinder head if you desire. Red Thread Locker would hold well and could be removed with some heat application if a need arose to replace the stud.

Water seepage should not be a concern as the gasket design will likely prevent water entry into the valve area/valve cover. Note the threaded center stud passes through the vertical "spine" of the valve cover gasket and there is a wide, solid machined surface for each face of the gasket to seat against.

Also, it's not uncommon for the heliCoil bit to pass through the head's stud location; there's an open area behind the stud; between the head and cylinder. I recall as my helper did the same drill through when he was helping me add a Helicoil.

Hope this aids you rather than muddy the waters.   Monte