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

[Atvjoe]

Hi everyone I just installed a new pump after mine failed. I had zero psi and I cleaned pressure relief. I replaced oil and seals on the metal lines.

So I installed a new pump and it won’t prime or do anything I need some help. Do any of you guys have any pointer what I need to do. I followed instructions added new oil and replaced filter and let tractor idle. But nothing

 

[rScotty]

No output from a new pump usually means there is an air leak in the suction line to the pump. If so, It's pulling air instead of oil into the pump.

The problem is that suction side air pinhole leaks are hard to find. If you have any rubber hose on the suction side just replace it - especially if the hose seems wet.

And what is this weird assembly? Sure doesn't look stock. Could air be getting into the pump there?

 

[TractorTech]

Agree @rScotty. Most likely leaking at that suction tube joint, and yes, it is stock! (27, 28). It could also be leaking at the filter connection(s)

 

[Atvjoe]

Thanks for the reply is this is a factor connection, I purchase new oil rings for everything I opened. I will check and see again but I was very sure everything was tight and sealed.

 

[Atvjoe]

Agree @rScotty. Most likely leaking at that suction tube joint, and yes, it is stock! (27, 28). It could also be leaking at the filter connection(s)

Thanks for replay I removed Tube #21 and bought the seal #22 for the front and rear of tube 21 just in case. This is a head stumper.

 

[TractorTech]

You might try pressurizing the transmission/rear end through the filler hole to see if you can get the pump to prime

 

[Atvjoe]

You might try pressurizing the transmission/rear end through the filler hole to see if you can get the pump to prime

That might be a very good idea. I will try it tomorrow after work. I would hate to remove pump and return it before trying everything.

 

[oldnslo]

Disconnect the pressure line and pour a little oil in it then bump the starter with the pressure line off. This will help purge an air lock but be careful if engine starts since will pump oil onto the ground.

 

[Atvjoe]

Disconnect the pressure line and pour a little oil in it then bump the starter with the pressure line off. This will help purge an air lock but be careful if engine starts since will pump oil onto the ground.

Thank you I did take off the suction side and filled it and added oil to pump. I will try it after trying to pressurize the transmission as mentioned by tractor Tech

 

[rScotty]

Thank you I did take off the suction side and filled it and added oil to pump. I will try it after trying to pressurize the transmission as mentioned by tractor Tech

I think that pressurizing the transmission sump is a great idea.... don't forget to plug the transmission sump vent tube - where ever it is.

A little pressure might also prime the system if the output from the pump is loosened. And it may also show up any suction leaks, which is something I've never found a way to do.

My hat's off to Tractor Tech for coming up with the idea.

How much pressure do you guys think would be necessary?
I'd say to start with low pressure/high volume...with the goal of getting the air in the sumpn up to somewhere in the 5 to 20 psi range.
My guess is that's about what the output of a vacuum cleaner puts out. No harm in starting low.
rScotty

 

[LouNY]

I'd be a bit leery of pressure in the case, anything over a few inches of water pressure can blow or damage seals enough to start leaks. There is approximately 27.7 inches of water pressure per pound of pressure.

I'd be more inclined to remove a discharge hose to remove any back pressure in the system and or use a shop vac to draw oil into and through the pump to prime it.

 

[dieselscout80]

On my IH 424 I always have to crack the output on the hydraulic pump in order to get it to pull hydraulic oil into and out of the pump due to air lock.

The filling of the pump prior to installation is a good idea and using a shop vacuum to suck oil into the pump may work too.

 

[Atvjoe]

I think that pressurizing the transmission sump is a great idea.... don't forget to plug the transmission sump vent tube - where ever it is.

A little pressure might also prime the system if the output from the pump is loosened. And it may also show up any suction leaks, which is something I've never found a way to do.

My hat's off to Tractor Tech for coming up with the idea.

How much pressure do you guys think would be necessary?
I'd say to start with low pressure/high volume...with the goal of getting the air in the sumpn up to somewhere in the 5 to 20 psi range.
My guess is that's about what the output of a vacuum cleaner puts out. No harm in starting low.
rScotty

Thank you for reminding me of the transmission sump vent, which I completely forgot about and I will be trying it first with a vacuum pump because my compressor is damaged and the only thing I have since I do refrigeration is nitrogen tanks, but I can regulated up to whatever psi I need. I will keep you guys posted later on today after work what happens thank you.

 

[Atvjoe]

I'd be a bit leery of pressure in the case, anything over a few inches of water pressure can blow or damage seals enough to start leaks. There is approximately 27.7 inches of water pressure per pound of pressure.

I'd be more inclined to remove a discharge hose to remove any back pressure in the system and or use a shop vac to draw oil into and through the pump to prime it.

That is awesome. Another great idea to try out today.

 

[Atvjoe]

On my IH 424 I always have to crack the output on the hydraulic pump in order to get it to pull hydraulic oil into and out of the pump due to air lock.

The filling of the pump prior to installation is a good idea and using a shop vacuum to suck oil into the pump may work too.

I tried cracking the output, but nothing came out. I did not try the vacuum pump thank you for the idea

 

[dieselscout80]

I tried cracking the output, but nothing came out. I did not try the vacuum pump thank you for the idea

When I did it the tractor was running and made a mess.

 

[TractorTech]

Below 10 psi is what I would recommend. I don't think the seals would be harmed at that pressure. I wouldn't worry about the vent

 

[rScotty]

Thank you for reminding me of the transmission sump vent, which I completely forgot about and I will be trying it first with a vacuum pump because my compressor is damaged and the only thing I have since I do refrigeration is nitrogen tanks, but I can regulated up to whatever psi I need. I will keep you guys posted later on today after work what happens thank you.

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

 

[gstrom99]

Hi everyone I just installed a new pump after mine failed. I had zero psi and I cleaned pressure relief. I replaced oil and seals on the metal lines.

So I installed a new pump and it won’t prime or do anything I need some help. Do any of you guys have any pointer what I need to do. I followed instructions added new oil and replaced filter and let tractor idle. But nothing

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

 

[TractorTech]

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.