Oil Pressure

cs930 · Jun 24, 2010

I was plowing last fall with my Farmall 400 when the oil pressure gauge started showing low pressure. I put a test gauge on the engine and found that I only had 12psi at about 3/4 throttle. I pulled the oil pump and found that the gasek was blown between the pump halves. I replaced the gasket and refilled the engine oil. I fired up the tractor and now the gauge on the dash and the test gauge read 0psi after 15 seconds of running. What could cause this?

jbradley · Jun 25, 2010

Had a problem with an M I purchased. I milled the lower plate at the bottom of the oil pump. There were grooves, very slight, worn in that plate from the meshing gears turning. Sometimes takes some experimenting to find it. The milling brought my oil pressure right back to normal.

KenB_Texas · Jun 25, 2010

When I rebuilt my pump on my 300 I used a piece of window glass and some 400 wet paper with cutting oil. It takes some time and patience but it works well to take minor imperfections out of the bottom plate.
A back window from an old pickup is about the flattest surface an average homeowner can find.
A side benefit is that it is safety glass.
I keep one on the top of my second workbench (used to use it to build wings for RC aircraft).

cs930 · Jun 25, 2010

When I replaced the gasket I used the glass and sand paper methed to remove some scoreing on the plate. Is it possable that the pump is just having trouble picking up prime?

M Diesel · Jun 25, 2010

Generally not, but strange things do happen. An easy way to prime is to force oil into the pressure port.

And you may have wiped a bearing...

Oil Pressure

cs930

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jbradley

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KenB_Texas

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cs930

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M Diesel

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