3.9 bits to 3.5

[Goldpanner]

Hi newbie here, be gentle with me !

Ive got both a 3.9 Rv8 and a 3.5 RV8 (long story !!) However the 3.5 has the SD1 front end on it with the P6 water pump (the small short one)
Would this fit onto the front of the 3.9? as thats the beast I want to use.

Also it looks like the main bearing seal in the rear of the 3.5 is leaking.
Is this an easy job to do to replace it or a beast?

Many thanks for the forum, posts and help !

[ChrisJC]

Both straightforward.

The front end should be a straight swap.

The rear oil seal is pretty easy, but it may be caused by a worn crank (fixed by putting the new seal in at a different depth), or some other leak from around the rear main bearing cap.

Chris.

[ian.stewart]

The rear seal leak may not be the seal leaking, very often the manifold valley seal leaks at the rear, runs down thw back of the engine and looks very much like a crank seal leaking.

[Goldpanner]

The rear seal leak may not be the seal leaking, very often the manifold valley seal leaks at the rear, runs down thw back of the engine and looks very much like a crank seal leaking.

Thanks for all that. Im 99.9% sure its the rear seal. The bit of engine between the valley and the crank is relatively clean and the leaking seams to be coming from the bottom half of the seal. (Orange type thing)

AlsoI have a compression tester, Is it possible to test compression turning the engine over with the starter or does it need to be running

[ChrisJC]

Test compression with the starter.

Chris.

[Mark]

Didn't the 3.9 have an odd front pully with some kind of extra balancing to make up for the heavier 3.9 pistons ?

Mark

[ChrisJC]

Interesting, not heard of it, but that doesn't mean much!!

Chris.