timing question

JimDog · 05-23-2002, 10:05 PM

I just finished checking the timing on my '71 T, and I'm a bit puzzled. First of all, I could not read any of the labels for the marks on the pulley. So I assumed that the two right next to each other were Z1 and 5, and expected one or the other of them to line up with the mark on the fan housing. However, once I got the timing light connected and aimed at the pulley, a completely different mark seemed to be the one lining up with the mark on the fan housing. This mark seemed to be maybe ~30 degrees past the two that I expected to be Z1 and 5.

I first suspected that I'd clamped the timing light pickup onto the plug wire for some cylinder other that #1, but that wasn't the case.

Obviously the spark is not firing ~30 degrees after TDC or the engine would not be running as well as it is (or running at all for that matter).

The only thing I can come up with is that the fan pulley was installed incorrectly, rotated some amount past where it should be. Is this possible? Other ideas?

Thanks,

-j

Early_S_Man · 05-23-2002, 10:30 PM

Jim,

Your pulley has three notches at Z1 (TDC -- leftmost when all three are up near crankcase split)) and 30° Before TDC, and 35° Before TDC to the right.

JimDog · 05-23-2002, 10:38 PM

So I assume that Z1 should be lined up with the fan housing mark when I'm setting the timing? I guess I'm confused now because I was expecting to align a 5 degree BTDC or ATDC mark rather than Z1 itself...

-j

Early_S_Man · 05-23-2002, 11:03 PM

Actually, no adjustment is made at idle ... the timing is adjusted to 35° BTDC at 6000 rpm, and the oil should be warmed up to full operating temp. before making the adjustment! All that is needed is a very brief time -- a second or two ... at 6000 rpm!

si2t3m · 05-24-2002, 05:08 AM

It just might be that you have alot of advance even at idle.

First time i started my 3.0L i had over 35btdc at idle. Maybe the MSD unit help to get the engine to catch due to the multispark stuff. I know this was not good but i got the timming corrected.

Don't know about the CIS stuff is related to the distributor (except for vacuum lines and advance curb) but i'd say that you can get away with a 3.0L dizzy and a 6pin cdi box and it's wiring harness (i always see the wiring harness for the CDI as an independant thing) or with the 3.0L dizzy and a MSD6A or 6AL unit.

HTH