High Oil Pressure -Checked Mechanically
11-08-2015, 09:56 AM
#1
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Year: 1999
Model: Cherokee
Engine: 4.0 I6 HO
High Oil Pressure -Checked Mechanically
My oil pressure gauge was showing almost 80 PSI if i touched the gas peddle for the past few days. It stopped and acted normal after about 20 minutes of driving.
I finally got time to check the pressure with a mechanical gauge. At cold start the pressure grew right to about 44psi. Then i waited about 60 seconds and revved the engine, pressure jumped right to 80 but then it dropped to 55 with the engine still revving.
Now after 10 minutes of idling its sitting at 29psi idle and 60 psi revved.
Motor is toast? Idk what to do now.
I finally got time to check the pressure with a mechanical gauge. At cold start the pressure grew right to about 44psi. Then i waited about 60 seconds and revved the engine, pressure jumped right to 80 but then it dropped to 55 with the engine still revving.
Now after 10 minutes of idling its sitting at 29psi idle and 60 psi revved.
Motor is toast? Idk what to do now.
11-08-2015, 10:01 AM
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Year: 1999
Model: Cherokee
Engine: 4.0
My oil pressure gauge was showing almost 80 PSI if i touched the gas peddle for the past few days. It stopped and acted normal after about 20 minutes of driving.
I finally got time to check the pressure with a mechanical gauge. At cold start the pressure grew right to about 44psi. Then i waited about 60 seconds and revved the engine, pressure jumped right to 80 but then it dropped to 55 with the engine still revving.
Now after 10 minutes of idling its sitting at 29psi idle and 60 psi revved.
Motor is toast? Idk what to do now.
I finally got time to check the pressure with a mechanical gauge. At cold start the pressure grew right to about 44psi. Then i waited about 60 seconds and revved the engine, pressure jumped right to 80 but then it dropped to 55 with the engine still revving.
Now after 10 minutes of idling its sitting at 29psi idle and 60 psi revved.
Motor is toast? Idk what to do now.
Relief valve in the oil pump is sticking, or
#1 cam bearing is shelling out and blocking the oil port in the bearing.
11-08-2015, 10:24 AM
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Year: 1999
Model: Cherokee
Engine: 4.0 I6 HO
I should also mention that on occasion the motor has a few loud clicks at first start up. But I guess if the pump is sticking that could be the cause? No oil in parts of the motor = noises.
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11-08-2015, 01:47 PM
#8
For $60 plus gasket and effort he can find out.
Or he can just **** can it now and spend $2-3K.
His choice. I'll hedge my bet on the pump.
He can also explore for shavings, if so, toast.
Or he can just **** can it now and spend $2-3K.
His choice. I'll hedge my bet on the pump.
He can also explore for shavings, if so, toast.
11-08-2015, 02:16 PM
#9
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
11-08-2015, 03:40 PM
#12
In light of the other comments-
Drain oil in a clean plastic bowl. Dredge bowl with magnet. If you have no contaminates, change filter with Mopar or Pure1 and change oil.
If you still have the problem- oil pump.
Nothing in the OP indicates catastrophic failure.
I don't drink.
Drain oil in a clean plastic bowl. Dredge bowl with magnet. If you have no contaminates, change filter with Mopar or Pure1 and change oil.
If you still have the problem- oil pump.
Nothing in the OP indicates catastrophic failure.
I don't drink.
11-08-2015, 03:44 PM
#13
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Year: 1999
Model: Cherokee
Engine: 4.0 I6 HO
Originally Posted by cruiser54
What brand of oil filter are you using?
Could have come apart?
Could have come apart?
11-08-2015, 03:44 PM
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Year: 1999
Model: Cherokee
Engine: 4.0 I6 HO
Originally Posted by Jeep Driver
In light of the other comments-
Drain oil in a clean plastic bowl. Dredge bowl with magnet. If you have no contaminates, change filter with Mopar or Pure1 and change oil.
If you still have the problem- oil pump.
Nothing in the OP indicates catastrophic failure.
I don't drink.
Drain oil in a clean plastic bowl. Dredge bowl with magnet. If you have no contaminates, change filter with Mopar or Pure1 and change oil.
If you still have the problem- oil pump.
Nothing in the OP indicates catastrophic failure.
I don't drink.
11-08-2015, 03:58 PM
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Year: 1999
Model: Cherokee
Engine: 4.0 I6 HO
Debating this oil pump swap now that I hear a decently loud metal clicking in the top of the motor. I had to drive it home today.
Any tips or tricks on the oil pump swap?
I know to let my axle droop because im stock. Remove the starter. Dont want to remove the down pipe, those bolts will surely brake off.
Any tips or tricks on the oil pump swap?
I know to let my axle droop because im stock. Remove the starter. Dont want to remove the down pipe, those bolts will surely brake off.
Last edited by a_shirey; 11-08-2015 at 05:48 PM.