Moparnocar
Well-Known Member
Got a AFB I'd like to use, decent shape, but secondaries are stuck. Been using pb blaster, no luck. Any old school tricks? Thinking heat next, but have to be careful of aluminum/rubber
Disassemble it and you can try the soak in transmission fluid mixed with acetone. But it really does depend how abused it was. Do not put a wrench or pliers to the ends of the shaft. The steel is soft and will deform and twist, at which point the shaft is useless.
Sometimes your lucky and it is minor corrosion and the shaft has not bonded to the aluminum and you can get some motion.
But I have had other so bad, that to save the body, you have to cut the shaft out starting by slots at the blade hole to get sections of the shaft out through the venturi, followed by bending the blades to remove them. All while not damaging the bore of the carb. Really involved and you have to file any burs on shaft off to finish pressing out. So no damage to the body bores.
I would inspect the shaft closer, is it heavily pitted, does venturi have pitting. If so, may want to move to different carb. If it is a numbers thing, at least it is the secondary shaft which is pretty common between AFB.
I have even cut open the body of the carb that was no good anyway to see what and why it was bonded so bad and you would be surprised how corroded the steel gets along with swelling of the aluminum that lock the shaft to the body. It normally is on the inside (at the blades) where the body bore is necked down to fit shaft and prevent air leak that the shaft gets stuck. Good luck.
Why not try some EvapoRust and see if that helps. Penetrating lube doesn’t really dissolve rust does it? I’ve had stuff come apart from soaking in the EvapoRust before. Worth a shot if the oils don’t work.
Interesting... How do you heat the oil? Stove top?I have had good luck with hot engine oil and just letting the carb set in it for a week or more. I have never had to reheat the oil or have a carb shaft not loosen up doing it this way. The oil is too hot for my hand. I hope some way works for you.
Not important carb, just saving a buck. Just needs to lot drive . If I can't get it, I have a Holley for it, double pumper single feed, really odd carbIf it was mine and important, I would send it out to be professionally rebuilt. They have the proper tools, chemicals AD experience to do it correctly. A sign that I posted in my shop said "Do what you do, Don't do what you don't do" Follow that advice and your life will be better for it.