1920 Ford Hydraulic pump New install I need Help. It won’t Prime

[oldnslo]

I would not go much over 5 PSI and have used exhaust from shop vac for this purpose. Go to high and you start to damage seals, potentially crack a casting due to large surface area the pressure is acting on, etc.

 

[Atvjoe]

Start real low, a compressor or nitrogen tank is way too much pressure.

Consider that a vacuum cleaner pulls about 3 psi of vacuum.... that is what it takes to lift a column of water up a hose about 80 inches.
I realize that doesn't mean that the output side of the vacuum cleaner is the same psi, but it gives a ballpark idea.

I said earlier 5 to 20 psi. Now I'm thinking way less is better.... maybe 2 to 10 psi.

Putting a pressure gauge on the vent tube is probably a smart move. Hardware store gauges and some tubing ought to do.
Or if you have any inert gas for welding, you already have the right setup with psi adjustable.
rScotty

Sounds great I’ll try lower pressure just in case I do have a couple shop vacs that I can try

 

[Atvjoe]

What was the original pump failure? Did you replace the hyd filter, and/or any other screen in the system?

When I bought the tractor, the tractor had water in the transmission area so all the hydraulic fluid was contaminated. I have another posting of me cleaning the transmission cleaning it with diesel. I cleaned everything out changed all the filters cleaned everything.
Transmission was spot less.

 

[Atvjoe]

I would not go much over 5 PSI and have used exhaust from shop vac for this purpose. Go to high and you start to damage seals, potentially crack a casting due to large surface area the pressure is acting on, etc.

Thanks for the info

 

[Atvjoe]

When I said pressurize the case, I was thinking of putting the air nozzle in the hole surrounded by a rag; not real a positive seal. It won't take much to prime if the pump is good.

Thank you for the info

 

[Atvjoe]

Gentlemen many thanks to all. After trying the vacuum trick on the transmission the unit primed and started working instantly. Thank you guys. Hydraulics are back 100%