compression

Christopher Lee · Jun 25, 2014

If a tractor engine is testing at 75 p.s.i. on the tester, is there anything, besides an overhsul kit, that I could use to raise the compression? Thanks!

Alan K · Jun 25, 2014

It might just need a valve job. You can retest it by squirting some oil in the cylinders and then do the test again. If it stays the same, its the valves, if it changes and goes up its the rings.

rustygreen · Jun 26, 2014

If you can tell us what engine,tractor and year
you may not have a problem.Too many variables.

Bob · Jun 26, 2014

Start it up. Drive the SNOT out of it. Plow with it.

Then, after 50 hours of hard use, take another compression check.

Those old beasts don't need to be WORKED, they are not pets!

Allan in NE · Jun 26, 2014

Will it run? Can ya pull start it?

75 lbs is an oddball number for a compression test. Are you sure your gauge is good?

Allan

Geo-TH,In · Jun 26, 2014

A leak down test will tell you if you have bad rings, head gasket, or valves. Are all cylinder at 75?

Jason S. · Jun 26, 2014

You can also get a fitting to screw in the spark plug hole and hook an air hose up to it. Listen for air blowing out the exhaust or carb and that will tell you if you have valves not seating.

David G · Jun 26, 2014

It could be anything, up to low compression pistons. I would do a full compression test wet/dry with leakdown before assuming anything.

RN · Jun 26, 2014

Need actual tractor- on a F20 project the manual notes 60 to 75 pounds is normal, JD A,B all fuel also that range. A ac WD45, Ford after the flathead N, M or 300 Farmall, would like 100+ pounds and later than that 125 pounds is a starter. RN

compression

Christopher Lee

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Alan K

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rustygreen

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Bob

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Allan in NE

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Geo-TH,In

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Jason S.

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David G

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RN

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