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Engine Baffling

Louavul

Well Known Member
Gents: Began installing my engine baffles and ran across this issue right away.
Seems the flange on the rocker cover is interfering with the baffle screws.
Just courious if anyone else has had this and how did you deal with it?
I figure notching the rocker cover is the way. Thanks!

o4a.jpg
 
Screws

Stainless allen head screws (aircraft spruce) work great and wont interfere with cover. Flat washer and star lock washer under the screws same as most other Lycoming fasteners.
 
Consider replacing or adding thickness to the half moon piece until it is thicker than the valve cover interference.

This would avoid the need for different or custom screws or washers.
 
close

Steven,
Before doing anything rash............
The relationship of the threaded hole and the valve cover has little to do with the baffeling. From the picture it appears the cover flange is bent over, possibly from the screw pressing on it. You may be able to massage the fit by rebending the flange back up. You might also try another brand of valve covers, etc.
IIRC the pusher guys have to safety wire these screws and use a different size head (smaller) that is drilled. That might help as well.
For the record, what brand cylinder is it?
Good luck.
 
I agree with Bob Martin - the amount of interference looks almost like the amount that the flange on the valve cover appears to be bent outward. I'd roll that back in somehow and see if it fits then. I've never had one that didn't fit, but they are always very close.
 
Space out the screw head with washers if need be, but don't grind the V/Cover flange, you will cause uneven gasket tension & leaks will result. Plus, your nice chromed V/C will rust there...
 
My two cents

I agree with the previous poster that the valve cover looks bent at that point. They are a close fit and if the cover is bent it would prevent the screw from going home.

However, the other poster made a good point, all bending must not compromise the sealing pressure of the nearby ridge on the valve cover or you will have leaks.

I would take a small hammer and gently bang on the ridge till it moves back enough to allow the bolt while doing so i would put a straight edge on the bottom of the valve cover and ensuring it does not go out of true.

Dave
 
IIRC the hole tolerances are rather loose on the valve cover.

Try loosening all of the screws and seeing if the cover will shift over a bit and remove the interference. :)
 
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