Difficulty installing new engine

Hello All, I have let my poor truck sit for awhile but I am working on it once again.

I am trying to put a 91 (I believe) 6 bolt (originally auto) engine into my 93 (manual) truck. I switched the flex plate for a flywheel, and replaced the thick bellhousing spacer used with the auto trans for the thin one from the manual trans. The engine and transmission both turn over freely by themselves but when I bolt them together neither the engine nor trans will turn over. I connected the clutch and it feels fine, but the engine still won't turn over even with the clutch pedal depressed.

I hope someone can help, I am sick of wrestling the trans on and off.

appreciatively

Colin

Hmmmm, I had that happen to a ford. I am wondering if your pinching something. As you pull the trany together with the engine, have you checked the binding in steps as the bolts are tightened. Also, is your starter causing the bind. Maybe some photos could help a bit. With all the work you did, I hope the drive shaft also isn't doing something. It's hard to guess when no visuals. Pilot bearing being installed correctly. Did you use the correct bolts with not having an oversized head on them to possibly cause a bind. These are my guesses.

I am using the original bolts that came with the flywheel to hold it on. I don't think the starter is a problem because I tried with it removed and same thing happened. I don't think the clutch is skewed in there because the pedal feels the same as it did when the truck worked, and the trans fit on there pretty easily. I'll go try loosening the bell housing bolts right now and sliding the trans backwards and seeing how far back I can go before it frees itself. Thanks for that idea!

Compare the starter motors. I believe there's a difference between the auto and manual starter motors (I think the manual has 8 teeth and the auto has 9...? and there might also be a difference in how far they throw the armature out to engage the ring gear)

I only have the manual starter

Well sorry to provide an unexciting answer but after more pumping the clutch and trying to crank the motor over more, it now turns freely. I don't have an explanation for it. Thanks anyway for your help!