Nut selection for carburetor repair

[Quickstep192]

I’m getting ready to replace the covers and diaphragms on the accelerator pumps on my Weber 40 IDA 3Cs. These things are fussy because the cover is pot metal and tends to warp if the attaching nuts are over tightened. If not tightened enough, they leak gas. The usual process is to tighten just enough to compress the lock washer, but then they tend to loosen over time.

I suppose the nut/lockwasher solution might have been an economical decision by Weber.

Economics are not a concern for me when buying 8 nuts, and I have options.

I can use lock washers and regular nuts as Weber did, or I can use nuts with nylon inserts or I can use nuts with nylon inserts and serrated flange.

What do you think is the ideal solution?

 

[Codyboy]

Some guys have luck with flattening out the cover.
http://forums.pelicanparts.com/pors...e-buy-parts-leaky-accelerator-pump-cover.html

 

[Skyman]

Perhaps a little blue Loctite?

 

[BurtEggley]

I would avoid nylocks. If the nuts grab the studs you may start having issues with the studs backing out instead of the nuts. The issue is that no one making these type carbs ever thought that people would still be using them for 30 -40 years on some model sportcars.

 

[four.cycle]

After trashing a perfectly good pair of 28mm Solex one-barrel downdrafts on my Opel 1.1L attempting to do something along this line, I would advise against making ANY deviation from the original set-up, but that's just my lousy opinion.

photo is not my engine.

 

[Quickstep192]

I just got turned on to Nord-Lock. They seem like a better lockwasher solution than a split washer.

 

[RoninB4]

-For carbs I try to use the low strength (222 purple) Loctite, it's made for small diameter fasteners that don't require much torque but still prevent the fastener from backing off. Been using for years of motorcycle carbs, no problems.