My brother and I are having a bit of a tough time getting his 66 corvair turbo to idle right. It was bought as a project, and we have gotten it to run, but seems to be way lean, as you either need to have the choke butterfly closed or your hand over the throat to make it idle smooth. Vacuum is about 15 in, fuel pressure 4 lbs. It is a Carter YH carb, supposedly the same as used on some tripower vettes. When you look down the throat with the engine running, it sure seems like it is getting way to much fuel out of the booster venturi. Should I even be seeing fuel out of the booster venturi at idle? It seems like it is getting plenty of fuel, maybe too much, however, it has me stumped because it runs better with the throat choked down. We have had the carb apart and everything appears to be clean and in order, but I'm uncertain how one ensures the metering rod is held down in the main jet properly by the dual purpose accelerator pump diaphragm.
hi, the only help i can do is pull up the corvair with all the hits.. these guys are more than likely subscribed to it so if you post there you may get some help.. here is the link to it in case you do not see it tonight. http://www.jalopyjournal.com/forum/showthread.php?t=189811&page=15&highlight=corvairs chris.
I was thinking a vacuum leak also, I made sure the turbo outlet to manifold seal was good. I will check the throttle shaft, thanks for the tip. What are the chances of air being drawn in the turbo shaft seals?
had a turbo covair in a dune buggy for pismo....... put a holly 2bbl on it & it came alive also ran engine oil thru the carb adapter to keep carb icing away.............
There were six different YH carbs used on the various turbo Corvairs. While the parts from all will physically interchange, they won't necessarily work. Initial throttle shaft to throttle body clearance from the factory was 0.004~0.006 inch. Measure with a dial indicator. If the clearance does not exceed 0.009 you are OK. Check the unloader adjustment of the flat hook-shaped rod passing through the auto choke housing. These are infamous for bending at the hook, and changing the functional position of the choke butterfly valve. Check the fuel valve. It SHOULD be spring-loaded; but the spring-loaded valves are more costly, and not found in the economy kits. And like others have mentioned, check for a vacuum leak. You should have more than 15 inches at idle. These are really great carburetors, but need to be right. Jon.
modeleh, please feel free to check out the latest Group here on the HAMB, " TURBOCHARGING & NITROUS OXIDE" . Hope to see you there, TR
Jon gave you good advice on the carb and yes there is a better than good chance that the seals are bad on the turbo. They do wear out and on a Turbo Vair unless it has been gone through the chances are better than not that you are leaking. Even if it has been gone though you stand a good chance of it being dry around the shafts and not sealing well. Try oiling the seals and see what happens.
Check the ignition wires for resistance. The original radio resistance core wires have a very short life. I had a '65 Corvair Turbo with engine running (ignition) problems that were cured by installing solid metal core wires.
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