Farmall M oil pump

I posted a little while back about getting an oil pump shaft
made I believe I may of found someone that can do it. You
can see in the picture that my gear is eating into the housing
but my question is how to remove the pin from the gear that
rides into the camshaft the little bronze looking pin is shown in
the picture how do I get it out do I need to drill away the little
head on the pin it?s on both sides
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Carefully measure both "buttons" if one is larger, drive tthe other one toward the big one. if equal, drilling might be the answer. if you put a new shaft into a housing where the gear has touched and worn, it will produce less pressure than you expect due to the gear now clearing the housing. The housing may also be worn where the shaft is supported. My advice get a good used pump. Jim
 
Its quite likely that's a solid tapered pin retaining the cam helical gear.

Sometimes one has to measure with a dial caliper to determine which end is bigger. The taper is very small and as such, it locks very tightly which is desirable inside an engine. Beating on the wrong end by making a mistake in assessing the diameters by eye can of course cause big issues.

If one has access to an arbor press that's a better way to go imo. Instead of having this impacting force that easily deforms the big end, its a force that has less of a chance of mushrooming the end. An alternative is to apply some force with the arbor press and then rap on the top of the ram with a heavy deadblow or soft-metal hammer.

At the end of the day, I would discard the tapered pin and drill all of the parts for a standard split-roll pin. In my opinion its a better choice because of the higher strength spring-temper steel at the shear point, and the expanding force of the "C" shape also "grips" all of the parts and keeps it from getting loose or flying out. Also its excellent at dealing with imperfect alignment or imperfect diameters.
 
How common is it though for the gear to be wearing into the housing? What your saying makes sense I wonder if I should just let it go the way it is if most used pumps are going to be the same as what I have now
 
I would say that is just a solid pin used in locations where a roll pin may fail and cause more problems. Measure as Jim suggested to check for a taper. I doubt it is tapered. Just have someone hold it for you over the jaws of a vise that are open enough for the pin to drive out. Supporting it only by the cylindrical end the pin drives through not on the gear teeth Give it a few good whacks with a tapered starter punch then drive it on out with a proper sized drift punch.
 
I think many used pumps will be pretty good. There should be less than .001 between the tip of a gear tooth, and the housing. If the oil is kept changed, the pumps don't get very worn. Flatten the plate and make the end clearance .001 to .0005 and a used pump will be fine. getting a good used pump from Steiner's, or Bates Corp, in Bourbon Indiana would be optimal. Jim
 
if you are still looing foroil pump for m farmall .I have one .it is checked out all specks check ok. it needs a base gsk.. I will take 50.00 plus 15.00 shiping.
 
I have made two or three shafts for M and H tractors. Buying a used one, I would say you have a 50/50 chance of getting the same or worse *unless* the seller has specifically torn down the oil pump and checked everything out.

I made mine out of drill rod. The first one has been in service for close to 15 years.

As Jim stated, end clearance is key to the pump working correctly (once the shaft problem is corrected).

The pin will drive out but at this moment I can not remember if it's tapered or beaded over on each end. Measure each side and if one is smaller try driving from that side. I'm thinking it's just a tapered pin.

I *do* remember that the key under the cam driven gear is a woodruff key so even with the pin out you don't want to drive the shaft out of the gear; rather pull the gear from the shaft and housing. Otherwise the key will dig into the top of the housing.
 
Think I have a pump out of a SM somewhere if I can find it. Going to be gone all day tomorrow but will try to remember to look for it Sunday. May have already surfaced the cover plate.
 

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