Pump running backwards?

   / Pump running backwards? #1  

lhfarm

Veteran Member
Joined
May 17, 2002
Messages
1,367
Location
Central Indiana
Tractor
NH TC40DA
Trying to restore a 3pt lift system on a 1949 Jeep. The system consists of a small pump mounted on the front of the engine and coupled to the crankshaft pulley, return & pressure hoses running to the rear of the jeep to the lift. The lift assembly contains the reservoir, control valve and ram. Had the original pump at a shop, which said the pump was too worn to repair. However the pump was the same as that used on the IH C tractor. I purchased a used C pump and it appears to be same pump. Put the simple manifold on the new pump and mounted it on the jeep. No output on the pressure side.

This is a small, geared pump. Would it work, regardless of the rotation? Can I simply reverse the manifold (return/pressure lines)?

Thanks,
 
   / Pump running backwards? #2  
Depends on if the pump was built to be bi-rotational or not. Most gear pumps have the shaftseal cavity vented to inlet so that pressure does not build up and blow the seal out. Some pumps have the bi-roational checks to allow for this venting and some do not.
 
   / Pump running backwards?
  • Thread Starter
#4  
Depends on if the pump was built to be bi-rotational or not. Most gear pumps have the shaftseal cavity vented to inlet so that pressure does not build up and blow the seal out. Some pumps have the bi-roational checks to allow for this venting and some do not.

You can see an exploded view of the pump here - http://www.cleancomputes.com/Cub/Cu...ub-Touch Control Manual/Cub Touch Control.pdf I don't have additional information. I'm going to reverse the manifold (and the hoses) and see what happens.

Why not just get a fan belt powered hyd pump like this.

Gear Pumps 250-058 Detailed Information

J.J. - I show this jeep at tractor shows and would like to use the original setup if possible. I have other pumps, but would really like to make this one work.

Thanks,
 
   / Pump running backwards? #5  
In looking at the exploded parts it is difficult to tell if the pump is biderectional or not.
 
   / Pump running backwards? #6  
Are the IN and OUT ports on the pump the same size.
 
   / Pump running backwards?
  • Thread Starter
#7  
Are the IN and OUT ports on the pump the same size.

Yes, the ports are the same size.

I reversed the manifold and it still didn't move the ram. I removed the pressure side line, with the jeep not running, just before it enters the control valve and the fluid dripped out. That didn't happen before.

Is it possible for the system to be air-locked? Also, I'm not sure the valve is working correctly. I've ordered a pressure gauge and it should be here next week. I'm assuming that should be my next step.

Thanks
 
   / Pump running backwards? #8  
If you can! Run hoses from the in and out and put the ends in a 5 gal. pail that is about 1/2 full. Start it up and there should be flow. See if that can tell you some thing.
 
   / Pump running backwards? #9  
You will know if you have hyd flow through the valve in an open center hyd system as the fluid is always flowing as long as the pump is pumping.

The pump may not have prime.

Is the suction port connected to tank?
 
   / Pump running backwards? #10  
What i'm getting at is there a screen in the tank.
 
 
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