i recently bought a short block from a grand cherokee and rebuilt it as there was alot of slug. i also took apart the oil pump and soaked it in Purple Power.
i also replaced the oil pressure sender as the old 1 broke in half.

i now have the motor back in the car, started it up and oil reads 0 when before it was fine
now with it reading 0 the motor sound like crap.
it sounds like rod knock.

im not comfortable running it with the gauge at 0.

does it matter it the motor is from a grand as the sensor is in a diff spot then a XJ?

 

"the motor sound like crap. it sounds like rod knock."

^^^^^^^^^^^^^^^
I think that's the important part.
Did you prime the pump or pack it with Vasaline before installation? Whats the clearance on the bearings: mains, rods, & cam.

 

i wasnt sure i had to do that.
i asked my father inlaw who had a 96 xj a few years ago
and he said it would be fine.
NOT

do i have to pack it with Vaseline or can i take out the distributor and run the drill in there to spin it?

 

should have spun it before starting it up.

doesnt sound bueno at all..

if the reading is zero and it sounds like crap, its probably best to start back over..

hate to say it, but you will be rewarded with the longevity

 

start over?
what do u mean by that?

 

He means pull the engine and tear it down to find the problem. You missed something somewhere along the way.

 

yeah, priming the pump.

 

only thing i didnt do is that

 

I would inspect the bearings, once you have a knock they are done.

 

what i heard was in the top end around where the rods are so i dont think ill have a problem

 

do i NEED Vaseline to prime the pump or can i prime the pump with a drill?

 

Exactly damage most likely already done...

 

someone answer my question

 

Auto parts store sell a "pre lube" that is used when rebuilding an engine.

It should be applied to all the bearing, and the oil pump.

I would not use vaseline, royal purple, grease, or peanut butter.

If you can get the pump to turn in present condition, try it.

The key words, "it sounds like rod knock", seems to be that you may

have ran the engine with no oil pressure, which probably scored/burnt

the bearings.

 

If you are going to tear the motor down and rebuild don't bother with store brand "pre-lube".
Use only MoS2 assembly lube, a little goes a long way. There is enough in this tube to do about 10 motors. Apply a small amount to the crankshaft mains and rod journals. Likewise a small amount to the camshaft journals and lobes. If you want to be really **** you can also do the rockers.


If you can't find it locally, order it here:
http://www.germanautoparts.com/Chemicals/Greasesandassemblylubes

Then, remove the cover from the oil pump and pack the cavity with Vaseline, replace the cover.

You can use a distributor shaft with a modded drive gear to prime everything before initial start-up if you wish. But with this method I never have, and I've rebuilt mucho motors. After 500 easy miles Every "new" motor gets an oil & filter change.

My first motor I did when I was 16 (a 1970 Buick 455) sits in the garage as we speak waiting for another project, I've always liked "ski boats", hmmmm.......