KBAM

alright, 91 3.0, pickup 4x4 m/t. Fresh HG. new water pump, flame throwers, valve job, timing belt, doug thorley headers, that's it. (Could there be more? Lol) Timing Belt is 100% installed correctly. (Checked again already, everything lines up)

The problem: timing is advanced 40*. Dies with anything less. I checked the dizzy, must have installed/reinstalled 5 times thinking I am off a tooth. For the life of me I can't get it lower than that. Followed the fsm to the letter.

Open to suggestions, I'm stumped.

KBAM

Friendly bump.

rustypigeon

When you jump terminals e1 and te1, do you hear the rpm drop?

scope103

If the truck runs at all with the timing at 40° BTDC, then I would suspect that you have a "spun" harmonic balancer (there is an annular rubber piece that separates the inner part from the outer part; more than one person on this site has reported that the rubber has failed, allowing the outer part to turn.) So your timing is actually set "close," but the harmonic balancer is "reading" incorrectly.

If the truck doesn't run, and you are unable to get the timing mark to move below 40° no matter how you twist the distributor, then the distributor is installed off a tooth (maybe two). There are 13 teeth on the helical gear, so being off one is about 28°. This is very easy to do. Try carefully marking the edge of the distributor (not the cap) next to the #1 plug output. Remove the cap, and set the crank to TDC. When set correctly, the rotor will be about 10° after the mark. If the rotor is 40° after the mark, you've found the problem.

Since you've tried following the FSM, try it again but turn it one tooth before sliding the distributor shaft in.

KBAM

Ever so slightly. Almost unnoticeable, but yes.

Excellent advice. Didn't think about the balancer. I found an earlier post (someone else's issue) from you stating the 28*/tooth thing, that's what got me pointed in the distributor direction. I'll give that another shot following the steps you provided here and see if that's the issue.

Thanks guys. I'll follow up later tonight.

scope103

To check the harmonic balancer, pull the #1 plug and put a plastic straw in there. Turn the crank, using the straw to tell when you're actually at TDC.

Why a plastic straw? You don't want to gouge the top of the piston, or damage the spark plug threads, with a screwdriver (a wooden chop stick works too)

KBAM

It's the balancer. Must have been damaged during the removal/installation. Bummer! Dizzy checked out fine, and tdc on #1 was about 1.5 inches off on the crank. I'll have to re-check the belt as well with the new pulley.

Off to buy a replacement! Thank you very much!