Mhmcp

New User
I acquired a non running SMTA, and know nothing about the history of the tractor. I have it starting, running and driving good. However, the hyd system is not working. It looks like the tractor was used for some time with the live hyd pump plugged off and the hoses to the Christmas tree area were missing. When I remove the two metal plugs from the pump very little oil tricked out. I put new pressure and suction hoses on and filled the suction hose with oil, cranked the motor over but no oil came out. I connected the suction and pressure hoses to the reservoir filled reservoir and started the tractor, no oil going to the remote cylinder. From what I have read using the tractor as they did with the pump plugged off may have ruined the pump. Anyone been down this path before? Any ideas appreciated before I tear pump down.
 
Make sure it sure it is primed before abandoning hope. Put 15 PSI in the reservoir to push oil into the pump. If no luck you might try the following. Use hydraulic rated fittings and hoses.
If you run a hose from the small port to a plain 1/4 turn ball valve, and the exhaust from the valve to the intake port, then fill it with oil, the pump should labor the engine(at slow Idle) when the valve is slowly and briefly edged toward closed. If no change in engine pitch the pump is toast. Running it closed is not at all good. To really check it you need a flow rater. Jim
 
Good advice above.
I would first check to see if the operating lever (pulled back) is actually moving the engagement shaft down on the pump.
I would also check the pump shaft couplings underneath, just to make sure the pump is being driven.
 
(quoted from post at 17:55:18 06/28/13) The pump was probably junk before they plugged it.The plugs were the 'nails in the coffin'.
I'm with you, the pump was no doubt toast before it was plugged. The only way you could run it without ruining it and not be connected to the hydraulic system would be to loop the pressure and suction ports with a long enough fluid filled hose to allow for some expantion as the fluid heated up from normal circulation. Still not the best idea, but better than running it plugged.
 
(quoted from post at 18:48:09 06/28/13) Good advice above.
I would first check to see if the operating lever (pulled back) is actually moving the engagement shaft down on the pump.
I would also check the pump shaft couplings underneath, just to make sure the pump is being driven.
I believe the SMTA has the live pump driven from the timing gears.
 
If they had the system plugged off the pump probably blew the seal as it had no place for the fluid to go built up pressure and there went the seal.
 

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