I was Just given a 1978 351M that was supposedley rebuilt then installed in the truck and then left to sit for six years without ever being fired up.Problem is it won't turn over so I suspect it is rusted up .I pulled the timing cover to find white assembly grease on the crank bearings.Any ideas on how to proceed from here?I think I should put oil in the cylinders to loosen them up before I tear the engine down,what would be the main source of the freeze up?Thanks in advance.
"bowties in the rearview mirror"

 

The pistons will be stuck in their bores and the rings may be rusted into the pistons. There is a chance that a new set of rings, gallery plugs, and gaskets might be all that it needs but the camshaft, lifters and springs may be ruined also. Some of the bearings may show corrosion.

A complete teardown, cleaning, and examination will be required. Check all of the machine work. Clean and examine all of the oil passages. Mike the bearings and plastigage them.

 

Before you get carried away, is the starter in it? If so make sure it isn't jammed.

 

Don't use the starter to turn it over, use a breaker bar to check any engine that has been sitting for a while.

 

How/where was it stored? I have had engines in storage as long as 10 years. I just tighten the rockers back up (loosened to take pressure off valve springs), poured some oil in spark plug holes and primed the oil pump. Never had a problem. The rings are prolly rusted to the cylinder wall. Don't use the starter. Starters make enough torque to easily break things.

 

Don't use the starter, and turn it SLOWLY with a breaker bar.

Good luck!

Bob

 

white assy grease? i put an engine together using white grease and by the time i had it all together the engine was stuck! i disassembled and checked everything, put it back together using the white grease again. stuck! repeat disassembly and check it all again, more white grease. stuck! one more time, using motor oil, without changing anything, it turned fine. what you can try is to pull the distributor and turn the oil pump using a 5/16", 1/4" drive socket and a 1/4-3/8 adapter on a speed handle if you have one, or a ratchet. maybe the oil pressure will wash out the grease from the crank bearings? maybe even drain the oil and use mineral spirits in the pan as a solvent! and a little mineral spirits in the cylinders too, to free up the rings and pistons from the cyilinder walls. that white grease is thick stuff, and seems to dry up over time. i have a feeling though that you'll have to pull the engine and clean it all out. another thing is, how well was the engine sealed up during storage? bugs and mice like to live in engines if they can get in. i've seen more than one engine with cylinders full of nesting material that would've crapped out the engine if it was started with the nest in there.

 

Years ago I put several engines together with white lithium with no problems.