My odd hydraulic problem and how I solved it.

[19478N]

I've been going through an early edit: [i:74f0f26b7a]front[/i:74f0f26b7a] distributor 8N that was yard art for about 15 years. It is now running well- I've done all the tune-up stuff, new wiring harness, clutch, oil pickup tube, rebuilt the carb, all the fluids, hoses, etc.

The hydraulics of course didn't work in the beginning. I pulled the pump and top lid and did a rebuild with parts from this site. Everything went through the parts washer and was spotless before reassembly. I flushed out all the old fluid from the trans, differential, and cleaned the sludge out of the case as well as I could. New Jubilee style piston. Correct fluid levels, etc.

Still no hydraulics. I pulled the top lid again, and with the engine running and PTO engaged, the pump spun but no flow (using the Rachel Gingell method of actuating the hydraulic valves with a lever while running). The valves move freely. I was convinced the relief valve was stuck open. I was ready to drain it all out and pull the pump again when on a hunch I thought I'd peek in to the valve chambers since you can pull the caps from the top. I found that there was no fluid in the chambers at all. So I filled the chambers up with fluid, reassembled it all, and it works 100%.

I guess I had assumed since the pump was fully submerged in the hydraulic oil that the pump would have primed itself, and although I've read a TON on doing this job (on this site, lots of YT videos, etc), I've never seen any reference to having to prime the pump manually. Other than using some of the hydraulic fluid as "assembly lube" while rebuilding the pump, I didn't fill any fluid in to the pump before reassembly.

Anyway, I thought I'd write this up to hopefully add a little info to the great amount of guidance I've gotten from this site already.
Thanks to all the contributors here, I've got a great little tractor for almost no money in it other than the parts, and it runs like a champ.

Thanks!

edit: the front/side because I'm an idiot.

This post was edited by 19478N on 10/14/2021 at 12:45 pm.

 

[HCooke]

Glad you got it working, but somethings do not add up. First a 1947 8N does not have a side distributor. Second, the pump will self prime if you let run long
enough (my experience).

 

[19478N]

(quoted from post at 15:54:40 10/14/21) Glad you got it working, but somethings do not add up. First a 1947 8N does not have a side distributor. Second, the pump will self prime if you let run long
enough (my experience).

You are of course correct, I brain farted and said side when I meant front (it's a 4 digit serial # 8N, so I'm assuming it was made very early).


As for the pump, I had operated the tractor for at least a couple hours after the pump was rebuilt, with lots of attempts to get it to work. Lots of on-off of the PTO, etc. and it never primed. So, perhaps it would have eventually, but it seems unlikely.

 

[jimtrs]

Agree, doesn't quite add up.
These pumps will self prime in short order. Maybe one of the valves in the valve chambers were stuck, and loosened up while you opened them? Maybe intake wasn't moving far enough?? The exhaust valve can appear to be working but not actually closing inside. Did you completely disassemble and clean the pump? Sludge has been know to sit behind the valves. 15 years of sitting will put corrosion in hidden areas. Anyway, glad it's working. Let us know if it keeps working. Especially after sitting a bit.

 

[hunkydory]

That is good information. Thank you!

 

[jmeyert4a]

Thank You... I'll be working on mine soon and I'll take your advice!

Jim