Still 31 distributor

Rip

Rip

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Currently my status is: this time definitely did set timing correctly and all gaps correct, etc. 👍
-stationary With idle at 500rpm, full retard, the vac gage needle shakes showing "late timing".
--stationary or moving, Advancing left retard/advance lever to 9pm or just pulling the throttle lever down, both or either causes vac gage needle to be steady in normal range but at 900 rpm.
---Carb air mixture is still inop since I had original "stalling on stop" occur. GAV seems to be working.
----driving seems fine, starts easily.
I guess my question is with everything electrically correct, why late timing at 500rpm but normal at 900?
 
You need to change the lever with changing RPM's to adjust the timing as you drive. Set and forget is just a compromise.
 
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Sorry I don't understand your answer.
I thought one started with full retard and advanced for normal driving with occasionally more advance for hills. When setting 500 rpm idle at full retard and then adding advance, it kicks rpm up to 900-1000 which is a little hard for me to downshift smoothly.
 
Lower your idle more at full retard to about 350 and at normal driving keep your advance about 1/2 way.. This should not bring your idle up to 900-1000...
Make sure your throttle lever at the carb is returning to the throttle stop screw and not sticking high..
 
Rip said:
Sorry I don't understand your answer.
I thought one started with full retard and advanced for normal driving with occasionally more advance for hills. When setting 500 rpm idle at full retard and then adding advance, it kicks rpm up to 900-1000 which is a little hard for me to downshift smoothly.
Click to expand...

On steep hills or occasions that stress the motor you might try "retarding" the spark a bit, not advancing the spark.
 
Vacuum gauges are good for checking out some problems, but I never use one to set idle. Advance lever all the way UP to start, then half way down when engine is at idle with stock engine. I have my idle at 450 to 500 RPM when the lever is half way down, then advance to about 2/3 or 3/4 for 35 to 45 MPH.

A vacuum gauge will pulse on a 4 cylinder engine, so don't worry about that.
 
Rip said:
Sorry I don't understand your answer.
I thought one started with full retard and advanced for normal driving with occasionally more advance for hills. When setting 500 rpm idle at full retard and then adding advance, it kicks rpm up to 900-1000 which is a little hard for me to downshift smoothly.
Click to expand...

Distributors that have an automatic advance, such as vacuum or centrifugal advance, the timing actually changes as the RPM's change. It is a constant advance/retard as the RPM's change.

Like I said, set and forget is just a compromise, for optimum timing it needs to change as the RPM changes.

Without an understanding of how a Model A engine works, and it's timing, a vacuum gauge can give confusing results. You results are exactly right for how you were using the gauge.
 
Yesterday, lowered carb idle screw to 350rpm at full retard and it kept running. Some adv, maybe half, had rpm at 500.
Today drove about 1/2 hour at 30-35 mph, think rpms crept up some and made downshifting tough ( for me). Concluded I forgot to adjust that adv/retard lever as driving conditions changed (old habits die hard). Took to rolling turns in 3rd gear to avoid grinding gears. Is this where I shud have "retarded" a little while keeping in 3rd to avoid bogging down (noticed nothing myself) around the corner or tried another downshift??

Sorry for taxing everyone's patience so I can move on to other problems with Henry😀. Just kidding they are all mine.
 
To down shift from 3rd to 2nd you shift to neutral, remove your foot from the clutch, rev the engine some, then push in the clutch and shift to second. If you match the ****** input shaft speed to the higher speed needed for 2nd gear, it will shift smoothly.

I don't play with my spark lever too much, but if you take corners in third gear you probably want no more than half spark advance with the stock head. Higher compression heads use less advance than the stock 4.2 compression heads, like my car has.
 
Tom has it right. My daughter calls the "double clutching" level two in learning to drive a Model A. She has really mastered the double clutching and is now at level 2.
 
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