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Author Topic: oil pressure question  (Read 3019 times)

Offline Jerry Wilson

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oil pressure question
« on: June 29, 2006, 03:02:14 AM »
  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
« Last Edit: June 29, 2006, 02:58:15 PM by Dallas »

Offline TomC

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Re: oil preasure question
« Reply #1 on: June 29, 2006, 05:55:28 AM »
When warm, it isn't uncommon to have 10-15psi at idle and 30-40psi at speed.  Good Luck, TomC
Tom & Donna Christman. '77 AMGeneral 10240B; 8V-71TATAIC V730.

Offline niles500

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Re: oil preasure question
« Reply #2 on: June 29, 2006, 06:01:45 AM »
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
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Offline Barn Owl

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Re: oil preasure question
« Reply #3 on: June 29, 2006, 06:08:35 AM »
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?
L. Christley - W3EYE Amateur Extra
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Offline DrivingMissLazy

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Re: oil preasure question
« Reply #4 on: June 29, 2006, 02:26:21 PM »
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
Life should NOT be a journey to the grave with the intention of arriving safely in an attractive and well preserved body. But rather to skid in sideways, chocolate in one hand, a good Reisling in the other, body thoroughly used up, totally worn out and screaming:  WOO HOO, what a ride

Offline Jerry Wilson

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Re: oil pressure question
« Reply #5 on: June 29, 2006, 05:16:29 PM »
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