My friend borrowed the truck to haul some garbage a few blocks from the house it backfired out the carb and no longer starts. It's getting spark the compression on all cylinders is 90 to 100 lbs. I have dumped gas straight it and it still won't hit. At TDC the rotor is about 25 degrees before the #1 plug post.

Any ideas? Someone said timing gear skip but 25 before (advanced?) isn't really all that off is it?

thanks