Thread: Why so much advance?

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Help me out here...I'm wracking my puny brain trying to figure this out.

Engine is a warmed over mopar 360, mild cam, MP ignition.

Why can't I find my timing marks, even with the light forwarded it to 60 degrees of advance? It's pathetic! It used to (before this new problem reared it's head suddenly)run awesome at 18 degrees initial...now it won't run unless I crank it way over...and the range at which it'll even run seems very tiny (IE I don't have alot of leeway to advance or retard the distributer before the thing just up's and stops running...not nearly as much leeway as I had prior). The engine at times runs like it's missing as well...

I've got a new timing chain and damper, so I would highly doubt them being the culprit. The car runs kind of rough, even when tuned by "ear" and is hard to start...it also likes to run hot now, and runs worse with time...

...don't worry about the right answer, but help me brainstorm, PLEASE! ask me anything, I've probably checked it at one point or another...it may help yours or someone elses thought process and ultimately help clue ALL of us in on the problem.

tia, chris

Did you install a new gear,and are you sure you got the timing marks lined up when you put on the new chain? some gears have 3 slots. did you you put it together at 0. try a vacuum gage to see what it does.normally vacuum should increase as you slowly increase rpm.

Originally posted by DennyW
First, I would say check your cap really good for cracks, and carbon tracks. When it's dark, use a water mist bottle, and mist over the cap and wires. Make sure the rotor hasn't burned through to the distributor. Oh, and make sure the distributor roll pin hasn't sheared, letting the gear move.

Just installed a new cap and rotor...no change. How would I check the roll pin?

The only thing that can do what you describe is the timing chain. The distributor gear slipping won't move the timing on the damper. You're going to have to pull your front cover. Check that the chain is the right one, sounds like its too long.

Originally posted by timothale
Did you install a new gear,and are you sure you got the timing marks lined up when you put on the new chain? some gears have 3 slots. did you you put it together at 0. try a vacuum gage to see what it does.normally vacuum should increase as you slowly increase rpm.

Yes, new gears and chain, installed with 4 degrees advance.

I hooked it up to a vaccuum guage while tuning the carb (shortly before the problem began...which was after trying on a new ECU box and coil which led the thing to not even run...and now with the old ECU/coi/ballast it runs as described) The vacuum gauge showed a steady 17 inches of vacuum at idle, going up to 25+ with increased rpms and higher when I let off the throttle altogether allowing the engine to return to idle speed.

It does have a weak, orange-ish spark.l

Originally posted by R Pope
The only thing that can do what you describe is the timing chain. The distributor gear slipping won't move the timing on the damper. You're going to have to pull your front cover. Check that the chain is the right one, sounds like its too long.

Sounds like I might do that this weekend if a simpler answer doesn't prove correct by then. Maybe I can see the chain with the fuel pump removed and a flashlight?

Pull a valve cover and watch the rockers on number 1 cylinder. They should be at split overlap when the timing marks line up, if they aren't, the chain has jumped. I should have said that different in my last post, the distributor drive gear won't move the timing on the damper when its set so the engine will run.

Checked voltage to the coil while the engine was running...got 10.5 volts...

DID NOT like starting though...at first I thought it was the ballast ressistor as it would want to die when I let the key off from the "start" position as that's when the ballast is bypassed.
EDIT: I will start it back up and re-check the vacuum for sure tomorrow.