09-03-2012, 11:23 AM | #1 |
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Join Date: Sep 2012
Location: sd, ca
Posts: 1
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Oil pressure drop
My rebuilt 54' 235 just turned 1000 miles. At start and while cold it idles at 30 and will reach 45 with increased rims
After running 10 minutes and Running hot it idles at 5 to 7 and the needle will move slightly with increased rpms. Looking for what normal is ....and comments on why pressure is so low while hot. Posted via Mobile Device |
09-03-2012, 05:46 PM | #2 |
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Join Date: Oct 2005
Location: Overland Park, Ks.
Posts: 5,229
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Re: Oil pressure drop
That seems like the pressure of the old splash system engine. Was it an exchange engine? Could someone have substituded an older engine for the original 54?. You might try a heavy weight multi vis. oil like 15w40.
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09-03-2012, 09:20 PM | #3 |
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Join Date: Sep 2011
Location: South West
Posts: 431
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Re: Oil pressure drop
Did they install a new oil pump, or just slap the old one back in?
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09-04-2012, 12:55 AM | #4 |
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Join Date: Jun 2006
Location: Idaho
Posts: 8,800
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Re: Oil pressure drop
My experience with 235's dates to the mid 60's. All I have had or observed had the oil pressure guage/tach. They have a very good oiling system that has pressure that varies with RPM. In my opinion 8-10 psi at idle is nothing to panic about. Warmed up off idle you should get about 25 psi which is adequate because the engine is designed for that. If it is really hot go to a heavier oil in the summer (I ran 20-50 in the summer when we lived in Phoenix area). If you are only getting a little above 10 off idle then I would suspect they did not replace the pump. Might also have bearing clearances that are on the generous side too.
Another thought, are you using the stock gauge? Might but an after market gauge on it and make sure the original is accurate.
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09-04-2012, 01:19 AM | #5 | |
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Location: Houston
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Re: Oil pressure drop
Quote:
I realize that 1 lbs per hundred rpm is acceptable but not on a new motor |
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