Been trying valiantly to restore proper operation of the automatic choke in my 1964 327/300. I finally freed up the stuck choke piston and replaced all the choke tubes in the clean air system, the deterioration of which caused the choke piston to freeze up in the first place (replacing these tubes is not much fun in a factory a/c car by the way).
A prior owner removed the choke plate(valve?)as well as the thermostatic spring in the choke housing probably to restore "normal" engine operation after the choke froze up. I purchased replacement parts and attempted to set things right, but the choke is not operating properly, likely due to ignorance on my part. Just a few questions:
How was the original choke plate/valve attached to the choke rod? Rivets or bolts? My rod had two holes which I expected to be threaded, but were in fact smooth. I tapped the holes to accept small bolts. Seemed to do the trick, but I'm still curious.
Which position should the thermostatic spring be installed in the choke assembly? The position I have the spring installed in now will hold the choke valve closed, but I cannot figure out what will make the choke valve open after the spring "contracts" when heated. Could this be vacuum? If so, any way to test if vacuum pressure is adequate to move the choke valve (e.g. remove the spring)? How tight should the piston be in the bore? Slight resistance? No resistance?
What should the clearance between the choke valve and air horn be for a cold engine? The shop manual says .070", but that's when a special .026" feeler gauge is inserted in a slot in the piston and the choke held shut with rubber bands--jeez! Right now the clearance with a cold engine is just about .000" I know this cannot be right, because the engine would not start at all with the choke valve closed (it flooded). I removed the choke valve/plate and the engine started but would not free from fast idle after warming up.
Other than the spring and valve plate, I'm fairly compfortable that I have all the other parts/linkages in the proper places based on illustrations in the shop manual. Still, I am still "flying blind" without another unit to compare to.
As always, thanks so much for your advice and help!
A prior owner removed the choke plate(valve?)as well as the thermostatic spring in the choke housing probably to restore "normal" engine operation after the choke froze up. I purchased replacement parts and attempted to set things right, but the choke is not operating properly, likely due to ignorance on my part. Just a few questions:
How was the original choke plate/valve attached to the choke rod? Rivets or bolts? My rod had two holes which I expected to be threaded, but were in fact smooth. I tapped the holes to accept small bolts. Seemed to do the trick, but I'm still curious.
Which position should the thermostatic spring be installed in the choke assembly? The position I have the spring installed in now will hold the choke valve closed, but I cannot figure out what will make the choke valve open after the spring "contracts" when heated. Could this be vacuum? If so, any way to test if vacuum pressure is adequate to move the choke valve (e.g. remove the spring)? How tight should the piston be in the bore? Slight resistance? No resistance?
What should the clearance between the choke valve and air horn be for a cold engine? The shop manual says .070", but that's when a special .026" feeler gauge is inserted in a slot in the piston and the choke held shut with rubber bands--jeez! Right now the clearance with a cold engine is just about .000" I know this cannot be right, because the engine would not start at all with the choke valve closed (it flooded). I removed the choke valve/plate and the engine started but would not free from fast idle after warming up.
Other than the spring and valve plate, I'm fairly compfortable that I have all the other parts/linkages in the proper places based on illustrations in the shop manual. Still, I am still "flying blind" without another unit to compare to.
As always, thanks so much for your advice and help!
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