S650G Hydraulic pump problems

[scubabandit]

I have a 650G that likes to eat hydraulic pumps. Yesterday I discovered that it has snapped the shaft on a second pump. Has anyone else had this problem? Any suggestions for a solution? Has anyone ever put a different hydraulic pump on one of these? The current system with the connector block seems like a very poor design to me.

 

[knothead541]

Had the same problem when I had a new connecting block machined. The material used was too hard. The block is supposed to give before the pump shaft.
I had a machine shop weld a longer piece onto the shaft to repair it and then used a 1/2" lovejoy connector. The rubber spyder wears out after a while but saves the pump.
You may also want to adjust the pressure relief on the power steering flow divider valve.

 

[Spruce Grouse]

Hi - just wondering where you get the 1/2" lovejoy connectors - I've had the same problem recently. Also, how do you adjust the pressure relief? (Sorry - I'm not much of a mechanic!)

 

[knothead541]

On units with power steering the flow divider is located on the right side just above the brake pedal. On top of the flow divider is a cap nut. Under the cap nut is a slotted threaded shaft and a lock nut. Hold the shaft stationary and loosen the lock nut. To reduce the relief pressure turn the shaft counter clockwise half a turn or so and re-tighten the lock nut while holding the shaft stationary. You want your pressure just high enough for your steering and other hydraulics to work properly. When you crank the wheels all the way left or right you put excessive pressure on the system and the valve is designed to prevent damage.
I buy my connectors at my local farm implement dealer. If you need more help just ask.

 

[Spruce Grouse]

Hello - the exact same thing has happened to me - were you able to resolve the problem? I am trying to get my (two) pumps repaired and will be looking for a different type of connector. Any suggestions would be appreciated.

I have a 650G that likes to eat hydraulic pumps. Yesterday I discovered that it has snapped the shaft on a second pump. Has anyone else had this problem? Any suggestions for a solution? Has anyone ever put a different hydraulic pump on one of these? The current system with the connector block seems like a very poor design to me.

 

[Spruce Grouse]

Hello again. I was talking to a supplier today and he wanted to know the series of the 1/2" Lovejoy connector i.e. L035, L050, L070 etc. Also, how is the connector locked onto the shafts - set screw? keyway? If a set screw, is it enough to keep it from turning on the shaft? I also went to a plastics place and inquired about using plastic material for a connector and got a couple of types of very hard plastic to experiment with. Thanks for your help!

 

[knothead541]

The connector I am using is a L-050. It has a set screw and that has been adequate. The shaft on the pully should have flat spots that you could set the screw into and you could machine a flat spot on the new pump shaft if you like.

 

[Spruce Grouse]

Great - thanks for your help!

 

[Jaydel29]

Great - thanks for your help!

I am doing a replacement after the local hydraulic shop is done going through my two blown pumps. The first was not rebuildable, they are looking at the second (Sparex replacement pump) now to see its internal condition.

I think a swap to a more "common" pump may be the best direction... AND the addition of a "flexible" coupler

 

[Spruce Grouse]

After going through a couple of pumps, it turns out the problem was in the 3-point hydraulic assembly which had to be dismantled and cleaned. The pressure buildup taking out the weakest point - the pump shaft. Seems to be working fine now.