Quote:
Originally Posted by Sieg
Just came in from setting the timing or attempting to set it. Got it up to temp checked idle timing and it was at 15.5*-16* as previously set. Bumped the idle speed up with throttle shaft adjusters, loosened the distributor and retarded to 14* but it want to float about +/-2*, snugged the clamp and it was still floating and idle was still high in relation to carb transfer slots. Loosened and backed the idle down (roughly 1,200 to 1,000) with ignition and it was still floating around, check it at had about 12* and tightened the clamp about 20 ft lbs. Revved the motor a little and it settles in at 4*. Revved it again and got a little backfire and flame through the carb. When I shut the motor off I thought I heard a subtle thump at the rear of the car. I also have noticed that the fuel pressure appears down from 6 psi to 5 while running and it bleeds off pressure quicker than usual after the motor is shut down. 
Stopped while typing this and went back at it and the car was hesitant to start, full pedal and it finally lit and acted fine. Check timing and it was a 4* as before, fuel pressure at 5 psi. Checked distributor hold down and it was tight. When revved the motor is slower than usual to return to idle. Tried again to set timing at 10 - 12* and the slightest rotation of the distributor (1/32") would take the timing from 4* to 12-16* and I couldn't get it to lock down in the 10-12* range it would lock lower at 4* or higher at 14-16*, locked at 4* and shut it off and heard the thump again and it sounded like it could have been the Flowmaster 80 series transverse muffler due to a backfire in the exhaust. Fired it again and it acted fine revved good decent throttle response and returned idle quicker.
-Distributor was loosened enough to turn but not without effort.
-Cap looks good.
-Rotor - contact arm was slightly loose (would move a 32nd with a little pressure), Loctited and snugged down.
-Inductive pickups in distributor are snug, clean, no damage. vacuum lockout is tight, etc.
-Geardrive ?????????
-Distributor gear ????????
-Fuel pressure issue???????
Something isn't right.............but the motor sounds crisp and sync'd at a 1K idle from behind.
I certainly don't trust the symptoms a this point. 
Any clues appreciated.  |
If you are using the lighter springs on the distributor advance, and your idle is high (over 1,000) then I'd bet your advance is just starting to kick in at idle. This would explain why the timing is inconsistent and changes so much when you just barely move the distributor. If you have one size heavier spring for the distributor advance then try that and see what happens.
This could also explain why the engine is not returning to idle properly.
Just an idea for something to try.