oil pressure question

[Jerry Wilson]

  I have an 8v71 in a 4107, the engine runs good and strong with no problems.But i do have a question about the oil preasure.When i first start the engine the preasure goes to 20 psi at idle then when reved up it goes to 30 psi max.I put a gage at the altenator oil line to check the accuracy of the gages on the dash and in the engine compartment and they were close the same.The gage has a flicker of about 2 to 3 psi, i would have thought the preasure would stay more steady.I know the book has a working preasure of 50 to70 psi .We have owned the bus about 2 years now, adding about 3000 miles with no problems but i like to head off any potential problems .I use 40 wt. oil .The book says low oil preasure could be caused by a plugged oil cooler or bad cooler relief valve.Has any one had a problem with a plugged cooler or valve.I know it could be bearings,pump or a number of things but i want to look at first things first    Jerry Wilson

[TomC]

When warm, it isn't uncommon to have 10-15psi at idle and 30-40psi at speed.  Good Luck, TomC

[niles500]

Jerry - the pressure under load should be closer to 50 PSI but at idle it falls real low - 5 to 10 PSI is not uncommon - FWIW

[Barn Owl]

My 8v71 seems to be a good healthy motor. No blue smoke a startup or running. I get what TomC posted. This worried me at first, but after reading several posts in various archives, I am starting not to worry as much. Any other opinions about these oil pressures?

[DrivingMissLazy]

You really do not have a low oil pressure problem. Quit worrying and enjoy!
Richard

  I have an 8v71 in a 4107, the engine runs good and strong with no problems.But i do have a question about the oil preasure.When i first start the engine the preasure goes to 20 psi at idle then when reved up it goes to 30 psi max.I put a gage at the altenator oil line to check the accuracy of the gages on the dash and in the engine compartment and they were close the same.The gage has a flicker of about 2 to 3 psi, i would have thought the preasure would stay more steady.I know the book has a working preasure of 50 to70 psi .We have owned the bus about 2 years now, adding about 3000 miles with no problems but i like to head off any potential problems .I use 40 wt. oil .The book says low oil preasure could be caused by a plugged oil cooler or bad cooler relief valve.Has any one had a problem with a plugged cooler or valve.I know it could be bearings,pump or a number of things but i want to look at first things first    Jerry Wilson

[Jerry Wilson]

Thanks everyone , the preasure will go down to20-25 psi when hot but will go back up to 30 psi at full throtle .I think i will still pull the relief valve just to make sure all is ok ,its not hard to get to. jerry