I've had this truck a little over a year and it is progressing along nicely... but I have a pretty bad rear main seal leak. I thought maybe the pan gasket but replaced it and turns out it's the rear main seal. My question is on ordering parts for it. I don't think it's possible that it's the original engine. The block is stamped C7ME-A and I know these blocks were used for ever and for everything but I would think 1967 cast blocks would be all used up by 1976.I have measured the stroke and it is a 390. The casting on the heads is C6AE R. When I order parts for this what do I ask for? Do I just say is a 76 F250 with a 390? It is an original looking FE motor with a 2 barrel Autolight 2150 carb. And I also need to put a cam chain and gear kit in also. While I had the pan off I reached up and felt the chain and it does have to much slack in it.
Thanks for any advice.

 

Your block could be about any FE, but it's probably close to the date of your '66 heads so you really can't tell until you get in there.

I believe all FE's have the same rod and main diameter so it really doesn't matter on your rear main seal.

 

When I last had my pan off in 1992, I wasdoing bearings. Saw the rear main seal wasn't gonna move, truck was in the yard, I was not pulling the engine, I left the old top half in the block above the crank, put a new lower half in the cap. It leaks a little, but most of my oil leaks from the pan gaskets and some from the rear of the intake valley pan at rear of the intake. On the flip side, my oil pan never rusted.

 

My rear main is leaking on my 70 f250 with a 360fe. I screwed it up when I built it a couple years ago. When I get to it, I will be pulling the engine. I would rather do that than lay on my back for who knows how long trying to do it under the truck. What kind of engine hoist do you have? I had the engine and tranny bolted together on my 72 f250 4x4 and could not reach from the front of the truck with the front cross member.


I had to pull the passenger wheel off and get it from the side. Thats with a Harbor Freight hoist. I think its definitely easier fixing the rear main out of the truck, if you have something to get it out and put it on an engine stand. If I had to do it now, I would probably have to pull the front clip off to get to it with this hoist.

 

You can drop the pan in a high boy and change the rear main in a few hours. done it many times.

 

Misread part of your post, wish I could delete this reply