Ok, I'm in the beginning stages of determining why my 4.0L I6 has low compression. I have a 93 xj 4.0 in my yj with unknown milages...been running the engine for 1.5years with the same issue. I originally thought it was my tranny going out, but because the motor was bogging down so much on hills I thought I'd check the health of the motor.
I did a basic dry compression check on and my results Front to back 102, 105, 100, 80, 105, 90psi.
I think put some seafoam in the intake/vacuum line to try and free up some sticky rings but no real such luck.
Second dry compression check after seamfoam.
90, 100, 102, 110, 112, 100
I then did a wet Compression test
124, 151, 130, 142, 135, 130
Does this mean my rings are done or something else?? I'm just wondering why all the cylinders are so equally low??? Does that the mean engine is just that old/worn. If so is there more I should be worried about than just rings? I still am wanting to do a leakdown test to see if there are any other issues with the motor before I tear into it. Just looking to see if anyone has any tips or advise.
I did a basic dry compression check on and my results Front to back 102, 105, 100, 80, 105, 90psi.
I think put some seafoam in the intake/vacuum line to try and free up some sticky rings but no real such luck.
Second dry compression check after seamfoam.
90, 100, 102, 110, 112, 100
I then did a wet Compression test
124, 151, 130, 142, 135, 130
Does this mean my rings are done or something else?? I'm just wondering why all the cylinders are so equally low??? Does that the mean engine is just that old/worn. If so is there more I should be worried about than just rings? I still am wanting to do a leakdown test to see if there are any other issues with the motor before I tear into it. Just looking to see if anyone has any tips or advise.