Oil Presure Guage? Take 2

[pyagid]

This is for my dads 304 again. He has a new mechanical guage in it.

New Oil pump gears, BT midplate, Bearings, Cam, Lifters,

When he first starts the jeep it reads 60psi, after it warms up it goes to about 20psi. at idle.

Last week he was driving it around for about 45 minutes or so, when it went to 0psi. This is what made him change the Oil Pump gears and install the midplate. He ran the jeep in the driveway for about 45 minutes, and everything was looking good.

Today he was out driving it again, and after about 45 minutes or so it went to 0psi again, He pulled into a parking lot, and just listend, Motor ran smooth, no noise nothing. We both figure the lifters should start tapping or something. He was annoyed decided to drive it the 3 miles home. The guage stayed at 0psi the entire way. Still no symptoms of low oil pressure except for the guage. He turned the jeep off, turned it back on again the guage went up to 5psi, then dropped again.

We are both thinking faulty guage due to the fact that the motor did no sieze, the lifters made no noises, and there was no other problems.

For the guage he has a copper line running from behind the oil filter to the guage, no kinks, or or anything.

Any other tips of places to look? or do you think we should start out by changing the guage? If putting a new guage in does not change anything what should we do from there?

Thanks in advance
Paul

[73hornut]

Try bleeding the air out of the gauge line. With the engine at warm idle, barely crack open the line fitting at the gauge until oil starts to drip out, retighten fitting. have rags handy, just in case.

[jeepsr4ever]

what spring are you running

[pyagid]

the one you sent him

[jeepsr4ever]

red spring then?

[pyagid]

yep

[Mudrat]

AND?????

It's been a week?

Mudrat

[pyagid]

Dad hasnt done anything yet, He has been busy with work, and today he drove out to cape cod, to get his seasonal oversand permit, so we could drive an fish the beachs. Tomorrow night i have to head down there and get some parts, and sell my YJ tub, so I will probably play with it then

-Paul

[Goose]

Hey Paul.. Let us know what you find out.. this is exactly what is happening with my CJ/304.. the electric gauge shows 20 psi at idle and I swapped in a mechanical and it reads exactly what yours does..it doesnt make a bit of noise. and has been running like this for who knows how long..(I just changed the guage this week) I have been wondering if the gauge could be bad or..The copper line the Autometer gauge in the J-10 has is twice as large(i.d. at least) as the the tiny little copper line with this gauge.. But since we are measuring pressure not volume I wouldn't think it would matter (however I have a long history of being wrong and would hate to break the trend now)

[pyagid]

Our other concern is that the we dont know the condition of teh cam bearings in this motor. If i remember correctly bad cam bearings could also cause bad oil pressure.

Is this true?

IF so i think he found a remanufactured short block for $450 that we are going to swap in

-Paul