Oil light on at idle
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?
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?
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.
Ron
I think a new engine is easier but more expensive.
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
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Senior Member
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From: New Hampshire
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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.
Herp Derp Jerp

Joined: Nov 2011
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From: Parham, ON
Year: 1999
Model: Cherokee
Engine: 4.0L OBD-II
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.
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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.
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.
Last edited by Firestorm500; Mar 25, 2012 at 12:05 AM.
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?
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
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
Ron







