So, I have a 1999 5.4 engine that has approximately 75,000 miles on it. It has not run for over 6 years. I'm putting it in my wife's expedition this week, and I need advice on what I should replace on the engine before I put it into the truck. When it came out of the donor, it was running well. I plan on replacing the front and the rear main seals, the spark plugs, the fuel injectors, COPS and rebuilding the entire upper manifold.

I see no evidence of oil leaks anywhere on the engine. The head gaskets and the valve cover gasket's appear to be in good working order. This engine was mine before it came out of the donor. I purchased it when it had about 50,000 miles on it. Regular oil changes and good maintenance between 50 and 70,000. It has been on an engine stand for approximately six years.

I'm wondering if I should bother with the freeze plugs, or possibly change the valve cover gasket's and/or the head gaskets. I really don't want to dig into the head gaskets as this necessitates camshaft and timing issues. Not that those are above my abilities.

What about dropping the oil pan and inspecting everything under that? Also, I was wondering about the exhaust manifold and the studs. They are rusted and taking them off may end up breaking one or two. More work.

Anything else that you guys can think up? I am really appreciative.

 

Rocker cover gaskets would be so easy to do now and such a pain to do later - and they're cheap. Don't know if you want to consider valve seals - I'm more into the old 302's so I don't know how complicated it would be on that motor (or if it even has them ?) but they do tend to dry out and crack if a motor sits for a real long time.
I know that there are several ways to do them without pulling the heads (air pressure or the old rope trick).
I'd suggest getting some new exhaust manifold bolts and changing them while the engine's on an engine stand - just in case you have to undo them later for who knows what reason; you'd sure end up wishing you'd changed them when the truck wasn't in the way.
That's all stuff that would be very simple on an engine stand compared to after installation.
As for sitting so long, it would be an idea to put in a bit of fresh oil and turn it by hand a few dozen times to get some oil pumped up and through it.

 

Exhaust manifold bolts and gaskets are looking like a much smarter choice now then I originally thought so I will change those. Valve cover gasket's are easy and will be changed as well. Valve seals will take me more time than I have right now so I'm going to cross my fingers, they do have a little bit of a complicated procedure in the shop manual and yes it would be a pain to do them in the vehicle. I do like the idea of turning the engine several rotations to get fresh oil in all the galleys. I had not thought of that

 

I wouldnt bother with the cam cover gasket myself. They are made to last eternity. Dont think Ive ever seen someone post about one leaking where that was the problem. If there is no evidence of head gasket leak (it will be around were the starter mounts up) I'd just go with it.

 

Hey guys, what about the water pump in the freeze plugs?