Front Hydraulic snow blower slows down when warm

[buffdan]

My neighbor adapted a Sheyenne CT500 hydraulic snow blower to his NH Workmaster 40.
Using a used Prince 540rpm PTO pump, This snow blower was originally attached to a smaller Cabellas tractor.
He is using 5 gallon tank, new filter, new AW32 general purpose hydraulic fluid, Sheyenne original filter block with safety valve, new proper sized hoses.
When he first uses it, it blows snow quite well, after 15 minutes or so, the blower slows right down, even with minimal snow. I measured temperature at PTO pump, snow blower motor and its around 150 degrees.
We opened the Prince pump, it was very clean. Had some wear in chamber for main gear.
Overall the snow blower has limited use since original. (unsure of history of PTO pump)
Any ideas on what to check, replace, adjust?
Is AW32 correct, does fluid make/weight matter?

Thanks!
Dan

 

[Dman1981]

Without flow meter
Or gauges it's just parts replacing

 

[D'oh]

AW32 is a very Light Hydraulic Oil especially @ 150F. Also a Cooler might be required for anything over around 140F

 

[grsthegreat]

Weird, I’ve been using my hydraulic blower for 10 years without a cooler. It uses 25 gallon reservoir though, so it doesn’t get very hot. It uses 22 weight hydraulic oil.

 

[oldnslo]

Did you check the temperature of the motor, safety block, etc. if one component is getting hot quick under load that is the component that is by-passing oil.

 

[buffdan]

Thanks for all the inputs, I appreciate it.
Have to try and eliminate pieces.
I have a pressure gauge, no flow meter.. Will do more testing, checking temps more closely

 

[oldnslo]

You will need to load the blower so that it slows down for the heat test and or pressure test. Speed dropping is some component by-passing oil and not building pressure.

 

[Dman1981]

Heat only a factor if one piece of the pie is doing it
Hydraulics in the desert run 220
Or more that's with coolers