300 U Hydraulic pump rebuild question 5

[Paul 300 U]

My local mechanic was able to remove the lug as discussed in previous post (question 4).
I continued the disassembly, cleaning inserting new parts and reassembling. I am stuck at the last step which is replacing the cover. I was able to fasten the cover once but the shaft would not turn. I tore down the pump and rebuilt to make sure I installed all parts correctly. This time before attaching the cover I turned the shaft and verified the pump is turning freely. When I had the cover part way back on, the shaft would not turn.

It seems the oil seal in thecover is impeding the shaft. I believe I inserted the shaft seal in the right direction but they look different then the originals which were completely encased in metal. The new are open on one side which I believe is the lip side which I installed facing towards the center of the pump.
If that is correct then my question is how far do I insert the seal? I stopped driving them in (using a seal driver) when the exterior metal top of the seal was almost flush with the top of the cover plate. That's how the originals looked. This seal will go further. Do I drive them in as far as possible? Is there another issue I'm missing.
Of course I'm concerned that inserting and removing the shaft is tough on the seal even though I'm being careful. For what it's worth the seal still feels perfectly smooth. Pics show: 1. Seal in question as inserted. (It's now uneven as I was testing whether it would go in further) 2nd and 3rd pic are from the backside. If you zoom you might be able to see remaining room. Pic 4 is just the pump body in case someone notices something incorrect on that side of the equation.
I appreciate the help. Paul

 

[Janicholson]

Can the non-driven gear be put in the wrong way? if possible the gear might be pushed against the housing. The seals look correct (though need to be even to the cover. They do not appear to be binding. Jim

 

[used red MN]

Is the rubber seal lip slipping onto to part of the shaft it rides on? It looks to me like it might be folding up when you install it. Might need to use a dulled down feeler gauge ..edges sanded smooth.. or small screwdriver to work it up over the ledge on the shaft. Is it just the photo or is the seal lip have a wavy look to it? If so your chance of it sealing properly is pretty low. If that is not just the picture making it look like that I would recommend getting another seal before putting back together. For this to be a leak free success, everything needs to be right on the money.

 

[Fritz Maurer]

I dont see anything wrong with the seal installation, possibly clearance problem with the gears and wear plates?

 

[Paul 300 U]

Thank you guys for your replies.
Jim
The instructions say to insert the shafts with the machine marks down toward the body. I double checked and that looks ok. I did flip the non drive gear to see what would happen and no luck. More info and pics below. Paul

Used red.
The shaft does seem to be fitting into the seal. The seal lip is pretty substantial, I haven't noticed it rolling. A new set of seals might be in order as you suggest but I'm not sure that's my problem.

Fritz
I think you are onto something though I'm not thrilled about it. When I just insert the gears into the bearings on the cover side of the pump I noticed the gear teeth are hitting the bearing and preventing it from rotating. I do notice there is a wear mark on the bearing with a couple small grooves. I lightly polished them out as best I could.
The teeth on the gear rubbing against the bearing obviously doesn't sound good like good news but I'm hoping there is a solution for it. The oginal reason for rebuilding the pump was because of leaking not because of noise or other issues so I'm puzzled why this is occurring.
Thanks again and I'll look forward to everyone's thoughts.
Paul

 

[Janicholson]

The bearing does push/rub against the gears. It is pushed there by the flat black spring with fingers. Make sure that is in correctly, and the fingers are in the indents in the bearing back. Also make sure there is zero particles under anything (unnecessary comment as you are very clean) Jim

 

[used red MN]

I realize you may have cleaned the parts off so any problems that our extra eyes would pick out would show up. But I just want to say when you assemble that the internals should be liberally coated with hydraulic fluid. Like nearly a couple teaspoons of it. The parts are built with clearances in particular the shafts and bushings. The clearance is there for the oil to fill and provide a cushion. I am just saying this because it may help it all fit together better. If the metal part of the seal is interfering with a shaft or gear you will have to figure out how to change that. Drive it in more or carefully tap it back out a small bit. I think the light reflecting on the surface of the seal is what I was seeing. I do not think you would assemble it if the seal looked questionable.

 

[Paul 300 U]

Thank you Jim. I was not searching for any indents when I was interested the spring hopefully that's part of the issue. Yes, I try to keep it clean.
The more I get into making the repairs the more I see the advantage of giving the tractor a good cleaning before disassembling. Paul

 

[Paul 300 U]

Used red mn. That's great information. I didn't know the parts were designed with clearance for oil in mind. I've just been smearing it on with fingers.
Also,when I zoomed in on the seal I could see what you meant by the seal having warped or rolled over. With all of the reassembling I'm concerned I might be doing some damage.
Thanks for the help. Paul