Stuck F-134 Engine

I have an F-134 that I can't get to budge. The oil looks good with no water, the water looks good with no oil, the starter just clicks, rocking in 3rd gear doesn't budge it, trying to turn the crank nut only loosens and tightens the nut.

So far I've:

- pulled the starter and tried rocking it - nope

- poured Mystery oil into the plug holes and waited a couple of days before rocking it - nope

- removed the rocker cover, rockers and head and poured mystery oil on top of the pistons and let it sit for a day. oil ran past pistons. Tried rocking again - nope

- tapped the tops of the pistons with an oak block and hammer and tried rocking it - nope

I'm currently letting it sit in Mystery oil, but think my next step might be to drain the oil, remove the pan and take a look at it from the bottom up.

Any other suggestions? I'm afraid I''m overlooking something stupidly obvious.

 

I usually give a stuck either a good does of PB Blaster or a 50-50 mix of ATF and acetone and let it sit for at least a week. Then about a 1/4 cup of the Marvel and another week sitting. Only then do I try to move it-with something on the crank snout. If none of that is to avail, only then pull the pan and rod/main caps. A couple of years back, we did that procedure on a 1937 White 706 bus that had sat since 1965. It was successful to the point where no engine work was required and the bus is currently back in tour service.

 

That's incredible! Can't argue with success...that procedure is going in my notes...good luck to OP.

 

Give the oil time. Are all the (exhaust) valves free?

Very hot water in the block when you try it again.

Have a friend standing on a breaker bar on the crank nut, while you pound on the oak.

Or, try towing it down the street and popping the clutch.

 

Came home from work today and tapped on the pistons again with an oak block and hammer, rocked it in 3rd, then gently nudged the breaker bar on the crank nut and felt a little movement! Tapped the pistons again and nudged the crank nut the other way and felt more movement. After five minutes it was completely freed up and turning all the way around. Now I'm letting it sit for a couple of days before proceeding. Any advice from this point forward?

 

F-134 is a strong engine (IMO) so I hope that soon you'll hear a very pleasant music.