What steps will i need to take on priming the new oil pump before and after installing it?
I did manually turn the shaft with oil in the new pump before putting the new pickup on .

I wasnt sure if id need to do anything like pull fuel pump fuse ,ecm,plugs , an bump engine a few times or what.To build pressure an lube engine before running.

Also do these require the gasket? the old one didnt have one on it but the new one came with one .
Its a 01 ,3.9,2wd.
thanks

 

When I changed the pump on my truck, the 'prime' was just putting some oil in the top of the pump at installation. Of course, that was with the engine still in the truck..... (not a rebuild) Pressure came up almost immediately at startup. It sure wouldn't hurt anything to pull the fuel pump relay, and crank the engine till pressure comes up.

 

Thanks.
Yea it's always better to do all you can manually before the real start.
Did you use the gasket ?
Mine didnt have one as I took old one off but the new one did.
Anything else of importance at 1st start up an reading pressure as it builds?

 

Nope, didn't use the gasket. There are nicely machined surfaces there. (that, and my pump didn't come with one. )

Just make sure you get pressure pretty quickly.

 

I would pull the fuel pump relay and crank for 5 seconds a few times.

 

If you're concerned about the bearings, pull the spark plugs as well. It takes the stress of compressing air off the main bearings.

 

Thanks .
Hasn't shown any pressure yet ..
So I'd just turn it over with no plugs an wires out[ already were off] with fuel pump relay out. in 5 sec intervals ?
I dont know if maybe I would see more of a rise after start but i dont want to harm the engine

 

With no load on the starter, (no plugs, so, no compression, so, no load) just crank it till the oil pressure comes up.

 

FWIW, my new engine made 75 PSI in about 20 seconds of cranking with the plugs in it.

 

Got it going..I did the 5 second turnover about 4 times an pressure began to rise.
I got high pressurer after 2nd start up [ this is right after I started it up cold]as it stayed running a few minutes .
I guess that's a good thing since a cold start up has a higher pressure before warm up .
Thanks !


Now we know on a 01,3.9,2wd you do NOT have to FULLY remove the oil pan to change all 3 ~ rear main seals,oil pump,an oil pan gasket ..An you can raise engine from the bottom too!
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