So before I drop in my replacement 3.9 I was going to change a lot of the seals since it was sitting for a year with no oil in it. Pretty decent shape I must say for sitting with no oil. Slight rust in the cylinders, cranks easily though.

I plan on changing the:

Valve cover gaskets
Head gasket
Plenum gasket
Oil pan gasket
Rear main seal
Oil pump gasket
Throttle body gasket

Any other major ones I'm missing?

Before I change anything I'm going to fill it full of oil and look for leaks.

Just want to make sure I'm not forgetting any.

Thanks

 

Timing cover

 

I know these 3.9s' are relatives to the old LA series of carbed (273/318/360) that you could pull the distributor put a shaft down the hole and spin with a drill to pump oil around. I wounder if this would help as pressurized oil may point out more leaks.

 

I read about this drill trick too, engine didn't come with a distributor in it so it'll be fun trying to set the timing.

Thanks for the suggestion Dan and Blue.

 

The 273, 318, 340, and 360 were all from the Mopar A block family of V8's - it's a fair stretch to go from these to a V6. The "drill on the pump" approach works really well as long as you can get to the pump from the outside. On a lot of the earlier engines, the distributor shaft attached to the oil pump, so pulling the distributor out and using a rod ground down to look like a big slotted screwdriver on the end of a drill would force oil all through the engine so that it wouldn't need to turn over dry. When the carbed engines became fuel injected, the early ones still had a distributor but the injection timing and spark (for the most part) were controlled by the ECU - the cam position sensor was located inside the distributor. When the need for a rotor and cap disappeared, the cam sensor still remained in what used to be the distributor housing, so if you still have this, you can pull it out and still use the drill & oil pump trick. If you don't have this, download the manual from the sticky at the top of this forum and see if there's any access to the oil pump from the outside.

 

The 3.9 is based off of the 5.2 and 5.9 and shares many parts. It does have a distributor, with the rotor and cap still.

The 3.7 did away with all that.