Two Cylinder John Deere Oiling

tdf46 said:

I'm looking for help from anyone who is familiar with the oiling system on a 1947 John Deere Model M.

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Ok, I guess that was too vague to draw any responders.

The issue is that my John Deere Model M engine (I've tried 2 different pumps) won't prime and build oil pressure. Has anyone seen this as an issue with their antique two cylinder JD engine ? I've inspected both pumps and neither shows any extensive wear to the gears, shaft nor body.

BTW, the engine is freshly rebuilt. The bearings are properly indexed to allow the oil to pass through the bearings and crank internal passages. I blew air through all of those. It just seems the pumps won't prime. Is there a trick I have overlooked to prime the system.

Have you tried different oil pressure gauge to rule out a faulty gauge?
May not be the problem, but it does happen.

One thing I've done is take a hand pump spot sprayer (you can get them at any farm or garden store) and adapt the hose to a pipe fitting that will thread into the oil gauge hole. Unscrew your oil pressure gauge and thread in the hose to the sprayer. Fill the sprayer with a couple quart of motor oil. Pump the tank up with the plunger to pressurize it. It will push oil through all the oil passages. I know my MT does't build much for oil pressure until its warmed up. I know on our Allis WD we have to run a fram filter. We ran a napa filter on it once and it wouldn't register any oil pressure.

I was just wondering if you ever found a solution to your oiling problem. I have a 48 "M" and it gets little oil to the head on the initial start while it is still cold. After the engine has been up to operating temp for a few minutes, it gets a very steady drop coming out of the front of the rocker's arm assembly, in correlation to the fan. I don't know if it is supposed to build up inside of the tube and go up over the rocker arm.