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Binding choke and piston - it was the front jet!

NutmegCT

Great Pumpkin
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You likely remember my saga of having a choke that was impossible to use. Cable required two hands on the knob and one foot on the floor just to pull out an inch. Weeks of tweaking, tightening, lubing, etc. made it marginally but noticeably better - but still not easy to pull.

Today I got the new carb jets (after getting two new SM needles a few days ago - to replace the unmatched and bent set on the car). When I pulled the original front jet out (really tough to pull out) and slid in the new jet, I was amazed at how easily the new jet slid up into the jet assembly.

The old front jet (as well as needle) was bent. Would actually rock back and forth when balanced on a straight edge.

And now the choke works better than ever. So much easier to pull out.

I'll do the carb rebalancing and mixture adjustment tomorrow. But wanted to reveal the final answer to a question that had bugged me since February - figured it might help somebody eventually.

That slight bend in the carb jet and needle was causing the binding of both the vacuum piston and the choke mechanism.

Onward through the fog! And thanks again to all of you who made the many suggestions.

Tom
 
Sorry I wasn't paying attention Tom ... I hope you bought new springs as well. Both the jet return spring on the side of the carb, and the sealing spring around the jet (inside the jet housing) can cause choke problems.

I'm also fond of the "high tech" jet seals that Moss sells (which in reality are just standard O-rings). They seem to last much longer without leaking than the cork seals do.
 
HOW in the world would a jet get bent?!?! PO musta been a gorilla!!! sheesh!

amazing.
 
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