timing marks

[duragg]

L28 with stock single row pulley only driving an alternator. Inspected pulley and it looked fine when I installed 3 months ago.

 

Checked timing yeaterday and it is not where I THINK I left it. It was retarded to zero initial.

 

Either I screwed up the last setup.

Or it moved.

 

Question: if the thing slips because the rubber is going bad, will that make timing appear suddenly advanced or retarded?

 

I tried thinking it thru, pulley slips back compared to crank. But my brain locks up when I try to figure what a timing light would show.

[rossman]

It will most likely it will be retarded if your pulley moves relative to the hub/crank. Have you checked whether your distributor moved? Can you get it back to where you had it by turning the distributor?

 

You can verify if the pulley spun by putting #1 at TDC on compression stroke. The timing mark should be on "0" timing mark.

Edited October 9, 2011 by rossman

[duragg]

Yes I moved the Dizzy and reset the timing just fine and the RPMs responded and the engine power came back.

Since I last set the timing we reindexed the cam and I have had the cap off several times.

I may have just not set it where I though I set it last time.

 

With just an alternator would that be enough load to move the pulley? At 7k rpm I suppose.

 

I will check the TDC mark against real TDC.

Those fancy pulleys are not very expensive, probably a good idea regardless.