jamesebolton

for all those that just say replace the sending unit i have already done that and now it only does it when hot and idle did do it when idling cold!

It is a 2.5l 4 banger so far in the past year i have installed new cam with lifters new push rods new head new valves new rockers for the top end
for the bottom end i have only installed oil pump and all new mains and inserts.

i installed the new mains and inserts with oil pump because of this same problem a couple months ago.
last year i installed new lifters and cam because of the oil light problem and bending push rods repeatedly not going to go into that again

just wondering which one it is going to be this time the lifters or the crank mains

the motor isn't making any noise like the last time last time you could hear a rod knock and the time before that you could hear the valves rattling but this time i cant hear anything abnormal and still have power to pull hills good not overheating or any thing

it seems like every time i have it fixed something else comes along to make the oil light come on
Do you think I just need a new motor?

99 Purple XJ

May be your gauge is messed up

jamesebolton

alredy borrowed a gauge from my neighbor checked the pressure 5psi on the jeep to test the gauge i hooked it up to the comanchee with the same motor and it said 22psi at hot idle

may pop

What oil are you using? Try a straight 40 or 20w50 as a temp fix. When you changed cams did you do cam bearings as well? that is a likely cause of low oil pressure.
Ron
I think a new engine is easier but more expensive.

jamesebolton

right now im running 5w30 in it and when i changed cams the only thing that appeared worn is the lobes of the cam so i didn't change the bearings guess i didn't think that far ahead

sthon

Try some 10w40 and maybe a quart of MMO. Also make sure you have a good oil filter. What oil filter do you have on it now?

twistedunibody01

I fixed my head after I bought the jeep with a warped head! Ever sence I had low oil pressure. I switched to 20w50 fixed everything lol!

KJamesJR

There was another post on here about sludge build up. I don't know if someone has the direct link to it or not. However it sounds as if sludge could be the culprit here if you've done everything else.

jamesebolton

everyone i talked to said that thicker heavier oil would fix the problem but also accelerate the engine wear and cause the motor to die quicker

salad

Might want to talk to some people familiar with the 4.0L then. xW40 is actually factory spec in Europe. If you did something stupid like using 100% Lucas in there it would definitely kill it. But just going up a grade is fine.

jamesebolton

oh where can someone get mmo at? i might try that to see if it works

Firestorm500

You've got as bearing issue somewhere--probably in the cam bearings as you mentioned.

Either run it till it burns up or pull it and rebuild it all the way now.

Or disconnect the light and sell it.

Throwing parts at it or soaking it in thicker oil will not fix it.

Turbo X_J

How did the cam install go? 1 bearing nicked/gouged by a lobe can be a problem, if they are all nicked they will hemorage oil. For the crank and rods how did you determine bearing size?

jamesebolton

the only bearing on the cam is in the back of the motor it was a needle bearing and appeared to be in good condition.
the crank and rods have std size mains and inserts though it was odd how they wore before i replaced them
the crank in the middle had worn the bearings only on one side and not the other like it was out of alignment or something but a few mechanics said that was normal for 200k miles of wear

may pop

Not the thrust bearing but the press in bearings the cam rides on. And NO thicker oil will not wear the engine out sooner. The factory booklet that comes with your jeep tells you to run a heavier oil at higher temps. 5w 30 when hot is like running **** in your engine. The thicker oil just squishes out of the slower then the light weight oil.
Ron