timing adjustments

Posted By: wtucker

timing adjustments - 04/18/13 07:42 PM

When timing the engine how much should the mark jump around from 0 at idle? Should it be pretty steady or jump back and forth 5-10 degrees? I'm having a hard time finding my intial with the mark bouncing all over. What would cause it to bounce?

Posted By: RapidRobert

Re: timing adjustments - 04/18/13 08:01 PM

Quote:

What would cause it to bounce?

sloppy timing chain/gears and or dist lower tang in the inter gear rotational slop. Put the timing marks at TDC with the rotor on #1 then pull the pass valve cover & move the crank back & forth a bit & see how much travel you have till it makes one of #6 cyls' rocker arms start to move which'll tell you how much chain play you have. With your hand turn the rotor back & forth lightly to see how much tang play you have & dont turn hard enough to get into the springs. An aluminum 1/2" ID collar on the bottom of the shaft will elim alot of that. McMasters/Carr & others sell them. Make sure your timing light is hooked up securely

Posted By: 70satelliteguy

Re: timing adjustments - 04/18/13 08:32 PM

They all jump around some unless you go to a Crank trigger!

Mike

Posted By: deaks

Re: timing adjustments - 04/18/13 10:47 PM

I have put the dist shaft across the back of a vice and give the tang a tap with a hammer on both ends to tighten it in the slot.
But dont get carried away.

Mick

Posted By: stumpy

Re: timing adjustments - 04/18/13 10:59 PM

Be sure the vacuum advance hose is disconnected.

Posted By: Challenger 1

Re: timing adjustments - 04/19/13 12:18 AM

Broken or too loose springs in the dist will cause it jump around at idle also. My eddie headed 474 cammed 340 stays within 2 degrees at idle but at one point I had too loose of springs in there and the timing moved around at idle. I bend the tang that the spring attaches to in the dist to fine tune it.