On my '39 P-8 I can't get the idle down. It idles high. I have tightened the vacuum connections and have backed out the accelerator linkage as far as I can go.
My amp meter gauge on the dash indicated a '-30' almost all the way over to the left, it occasionally went to almost center- but stayed mostly 'left' in the negative range.
I drove it about 20 miles today-first time in a long time. So, once again, I need your help.
Just a question on the negative amp reading - is the battery hooked up properly? Positive ground?
Does your carb have a fast idle cam attaced to the linkage coming down from the choke butterfly pivot. If it does, chack to see that is is fulley releasing to allow the idle adjustment screw to rest on the thinest part of the cam. It is basically a tapered thickness piece of metal making a moveable ramp with the thicker part associated with a fully closed choke. If it does not fully release to the thinest portion, the carb will not idle down properly. If your car is equiped with a hand throttle is it fully releasing the in the off position
Does your engine idle smoothly and provide a wiithin spec reading for manifold vacuum.
with all accesories off, which direction does the amp gauge move when you turn the key to the swith position??? If wired properly assuming you have the battery wired polarity correct it should move slightly to the negative side.
Oh by the way did you ever get your timing sorted??? Did you ever decide what oil you were going to run???
Nice to hear back from folks if and when some help is tendered. Probably will be loathe to provide guidence on future queries without feedback.
Update and Reply on my '39 P-8
I stand corrected- Thank you Jim- I know better on the battery cables- you're right I had them wrong.
Oil- I decided to go with 15-40 Shell Rotella-T with the ZDDP additive. Out here in Az. just about no winters and the summers are very hot. I feel that this will be my best coverage.
Carb/idle- I am working on the cause and am checking the linkage suggestion by Ply46.
...not sure of how the vacuum would work- as I've never done that- instrument necessary to do that is-?
Thanks again for your help....Dennis
Vacuum gauge, attached to your vacuum port for the windshield wiper.
http://www.secondchancegarage.com/public/186.cfm
Dennis:
I had a similar probllem several years ago when I first started up my 39. I found that it was related to what I think is called the vacume advance. It is over in your distributor cap area and should be connected to your carburator. I ended routing a metal line from one of the ports in the carburator over the top of the engine to the distributor cap area to hook it up to what I think is called the vacume advance and that solved the problem.