Idle mixture screw stuck

[Chris75]

I'm trying to adjust the idle mixture, the screw won't budge, I suspect it's a dissimilar metal corrosion issue. The engine stalls at times when going to idle, recently installed indigo PCV kit. Ran well before. Is there another solution other than a new carb?
Thanks Chris

[Al Schober]

I'd try a combination of penetrant (PB Blaster is good), time, and heat. As for the heat, I'd avoid direct flame - it's not too controlled. Rather, I'd use an oven. Heat will cause the housing to expand more than the screw and might just loosen the screw. You've got nothing to lose.
Alternate to a new carb is a used one. Keep an eye open on eBay - they show up now and then at reasonable prices.

[rickandlee]

Just looking around in my area at things and look what I found.

https://yuma.craigslist.org/bpo/d/yu...792043030.html

[Marty Levenson]

For sure fix the idle screw, but if it ran well before installing the PCV kit maybe there is a tiny air leak to find.

[tenders]

My advice would be to customize a high quality screwdriver with the thickest tip that will fit into the slot. That will be a fairly large screwdriver, so you'll need to cut down the edges with a Dremel. This will become your dedicated carb jet screwdriver. Insert it carefully, press hard, twist forcefully, and accept whatever happens.

I had a problem like that with one of the jets a couple of years ago and stripped the head with my screwdriver. Just could not get it out. C'est la vie, I scrapped the carb. Maybe I could have dug it out with a series of holes drilled into the center, and a tiny EZ-out...but maybe not, and I'd blame every bad thing that ever happened to the engine on that repair.

Not sure if a best practice to head this off would be to apply a dab of anti-seize compound to the threads, but I've been tempted to do that the next time the carb comes off.

Interestingly, we don't talk about rejetting the A4 carburetor like people do who have motorcycle carburetors. Jets cost less than $10. Are we comfortable that the stock jets are the best jets, aside from the possibility of the adjustable main jet that Don sells?

[romantic comedy]

Interestingly, we don't talk about rejetting the A4 carburetor like people do who have motorcycle carburetors. Jets cost less than $10. Are we comfortable that the stock jets are the best jets, aside from the possibility of the adjustable main jet that Don sells?[/QUOTE]

We rejet bike carbs when we modify them to change the air flow but with the Atomic Four we just want them to run stock. I dont see much need to rejet.