REAR MAIN FROM HELL

i just replaced my rear main seal (4.0L ax15 139k) i had to pull the starter the steering stabilizer and the oil pick up tube. i had to use a hammer handle to pry the pan out. the nuts for the bearing brace where partly triangulated and the threads on one of the rear bearing cap bolts where the brace bolts to were partly flattened. i oiled both sides of the bearing witch i found out later is a bad idea. torqued everything to spec. when i took it for a 5 minute test drive it was knocking and pinging:firedevil. so i had to find out why so i did the whole thing again. when i got to the bearing cap bolt i tried retorqueing them and one was loose this made me think that the cap was never fully seated. so i pulled the bearing cap and cleaned the bearing with brake cleaner and only oiled the crank side this time. put it all back together all torqued to spec and the motor is still knocking and pinging. i have no idea what to do now, do you guys have any idea what i might have done wrong and what i should do next. thanks allot for reading this long post

You need to diagnosis what the noise really is. Rod, Crank, Piston, Timing chain. Then you can go from there.

pick up tube not picking up? if it's not, then continuing to drive it will end badly

is there a seal for the oil pick up tube? and is it normal for the tube to have some play or should it not move it at all?

my 92 knocks but i was told a lifter was bad

XJDP96 said:

is there a seal for the oil pick up tube? and is it normal for the tube to have some play or should it not move it at all?

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I think you are looking for a very tight "press" fit of the pickup tube to the oil pump--no, it shouldn't flop around.

i was thinking that it was going to be hard to get the tube out but it pulled out pretty easy and went back in just as easy. it doesn't flop around but i can move it. I'm just trying to think of anything that could be causing this noise, i know before i did the rear main seal sometimes when i was going up hills i would hear a similar sound but it was not as loud and it was only when the motor was working kinda hard. what are the chances that pulling the bearing cap just aggravated something?

XJDP96 said:

i was thinking that it was going to be hard to get the tube out but it pulled out pretty easy and went back in just as easy. it doesn't flop around but i can move it. I'm just trying to think of anything that could be causing this noise, i know before i did the rear main seal sometimes when i was going up hills i would hear a similar sound but it was not as loud and it was only when the motor was working kinda hard. what are the chances that pulling the bearing cap just aggravated something?

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that sounds like your trouble, your oil pump is cavitating, and your engine is not getting any oil, that tube is supposed to be VERY tightly fitted there

could that be my problem to instead of a a lose lifter

jamesxjowner said:

could that be my problem to instead of a a lose lifter

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when finding knocks.
high pitched knock is top end.
low pitched knock is bottom end.

Wouldn't the question of the oil pick-up tube sucking air be answered by the oil pressure gage?

Both times I did mine I just pulled the pump off - two bolts. I tore the gasket but just stuck it back on. The second time I put a 1 1/2 ton jack between the axle and frame to make some more room.

A loose pickup tube could suck air as it's easier for air to fill the vacuum the pump creates trying to siphon oil from the bottom of the pan. Air foamed oil would certainly cause a significant oil loss at the bearings as the air is quickly squeezed out, leaving no oil wedge to support the crank.

As this is an extension of a previous symptom, I suspect the pickup tube more than the cap. One thing to double check is the oil filter. Make sure it's a quality brand with no paper end caps on the filter element - ie. not the cheap orange ones sold nationwide. A blown end cap reduces or eliminates oil pressure causing knocking bearings.

thanks for all the replies guys and keep them coming. so if it's a pick up tube problem what do you recommend i do? and the oil filter is a napa gold no cheap stuff for my baby!

XJDP96 said:

thanks for all the replies guys and keep them coming. so if it's a pick up tube problem what do you recommend i do? and the oil filter is a napa gold no cheap stuff for my baby!

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I would pull the pickup tube and try to drive something into the tube to try and expand it for a tight fit.

Otherwise, get a new pump and pickup tube.