farmall h oil pressure

when it warms up oil pressure drops it has original oil guage it drops down to redline or real close cause and suggestions thanks

At what RPM does it get to the redline? What oil are you running? Sam

rpm throttle up oil 1030 runs good no noises iv had it 15plus yrs always been like that

The most common issue is a warped pump cover. This happens over time, and is a known issue. The bearings can contribute to the issue, but if it is a good runner, I would do the pump cover and see how that affects the pressure. The process is to remove the oil pan. then remove the oil pump (easy to do, and obvious) remove the lower cover (not iron) and flat sand it on a piece of glass with 340 grit paper and thin oil, or water. Use non directional motion and uniform pressure to bring it back to flat. Next use 600 grit to smooth it a bit more. The clearance between the rotor gears, and the cover (with the paper thin gaskets should be between .0005", and .001". Plastigauge can be used to measure this, or thin .0005, and .001 shim stock. Put a small tab of the stock between the cover, and a gear. Gently tighten it (with gasket) until with a .001 tab it begins to lock (do not force tightness) and with a .0005 tab of shim it turns free when snug. The gaskets can be found at caseih dealer, or made from material (very thin material) the stack or combo of gaskets act as shims to provide the clearance. All this costs is a pan gasket, and some pump gaskets and time. Best of luck, Jim

I have the same situation. I ran 10-W30 for a long time, then I ran 10-W40, now I've run 20-W50 for 10 years or so. I guess it's OK, it seems like I have 65 psi startup, and running around, and 30-35 psi or so warmed up and idleing. I GUESS it's OK, I guess I'm not damaging anything. I don't work my H hard anymmore.

My H has about 65 cold and around 20 at hot idle. It seems to do fine. I run 15w40 in it.
Zach

jim, the problem you are describing is on 'a' size tractors. a h or m has a cast iron bottom on the oil pump.

(quoted from post at 20:33:19 09/06/12) jim, the problem you are describing is on 'a' size tractors. a h or m has a cast iron bottom on the oil pump.

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Yes, the bottom cover on an H oil pump is heavy enough that it does not warp easily, but that thin little gasket can still blow out, and the gears inside the pump WILL wear some serious depressions into the cover, and when that happens, there will be a serious loss of oil pressure.

Milling the oil pump plate flat again and installing a new gasket isn't a whole lot more involved than an oil change. Can't hurt to try.

If you don't have a mill, you can sand it flat on a piece of thick plate glass with some emery cloth IIRC. You stick the emery cloth to the glass with 3M 77 spray adhesive, then rub the plate on it until it's flat.

looks like everyone overlooked pressure spring in pump , ive seen them brake , get weak , or plunger get stuck open , pumps in an H hardly ever warp , but it dont hurt to sand it flat if you take it apart , these pumps are built to last forever , so if spring & plunger are good you better check some bearings while your in there wont , if there good just torque them back up & rewire them main bolts , also dont know your location but everyone aroung PA uses straight 30w oil year round & for the most part thats what the owner manual will tell you unless your in alaska

(quoted from post at 16:37:05 09/07/12) looks like everyone overlooked pressure spring in pump , ive seen them brake , get weak , or plunger get stuck open , pumps in an H hardly ever warp , but it dont hurt to sand it flat if you take it apart , these pumps are built to last forever , so if spring & plunger are good you better check some bearings while your in there wont , if there good just torque them back up & rewire them main bolts , also dont know your location but everyone aroung PA uses straight 30w oil year round & for the most part thats what the owner manual will tell you unless your in alaska

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Those pumps WERE built to last a lifetime, but considering these tractors are already 59 to 73 years old, I'd say they have ALREADY lasted a lifetime.

are you just following me around rustyfarmall? just to make comments on my postings , i may not know much, but i work in an engine machine shop now for over 20 years , rebuild LOTS of these farmall engines 5 of which are mine still today , so take it how you may but these pumps are VERY RARE 1 in a million ever wear out if it came out of a running tractor ,unless your pumping saw dust its good, check the spring & plunger

(quoted from post at 07:59:07 09/08/12) are you just following me around rustyfarmall? just to make comments on my postings , i may not know much, but i work in an engine machine shop now for over 20 years , rebuild LOTS of these farmall engines 5 of which are mine still today , so take it how you may but these pumps are VERY RARE 1 in a million ever wear out if it came out of a running tractor ,unless your pumping saw dust its good, check the spring & plunger

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I speak from experience. My 1950 Farmall H had oil pressure issues. I dropped the pan, removed the oil pump, removed the bottom cover from that pump, and found the gears had worn depressions into that plate. Those depressions were a good 0.125" deep. I also took the spring out and checked it against a known good spring. There was nothing wrong with the spring. As I no longer have access to a milling machine (used to work in a machine shop) I used a large, flat file to restore the cover plate to its original state of flatness (dial indicator was implemented). I put it all back together, filled the pan with 15w-40 oil, and the oil pressure is now excellent. Just to further clarify, I went to SWCC in Creston, Iowa 1970-1971 and took the auto mechanics course. I then worked as a mechanic for a local John Deere dealer, later worked as a mechanic at a local Ford car and truck dealer, and also worked as a mechanic at an independent auto repair shop. In between mechanic jobs, I farmed, held a few other jobs, but always did ALL of my own auto repairs. Enough said.