PRM500 Hydraulic Box - Oil Change

[Paringa]

Hello all,

 

Running this idea past the group.

 

I have a PRM500 which is coming up for its annual oil change along with the engine. The gearbox manual states "use the same oil as the engine" which i have always done - a 15W 40.

 

PRM's are known for being clunky when going into gear and my question is:

 

Is there any merit to my using a gearbox oil say a 80W to so see if this makes it a little less clunky?

 

My thoughts are it probably won't make any difference and may cause more problems than it solves. But is it worth trying? I can always drain it out again...

 

Best regards

 

Par

[Boater Sam]

5 minutes ago, Paringa said:

Hello all,

 

Running this idea past the group.

 

I have a PRM500 which is coming up for its annual oil change along with the engine. The gearbox manual states "use the same oil as the engine" which i have always done - a 15W 40.

 

PRM's are known for being clunky when going into gear and my question is:

 

Is there any merit to my using a gearbox oil say a 80W to so see if this makes it a little less clunky?

 

My thoughts are it probably won't make any difference and may cause more problems than it solves. But is it worth trying? I can always drain it out again...

 

Best regards

 

Par

No, don't do it.

Use 15w40 NON synthetic.

It should not be excessively clunky if the engine tick over is not too high and if there is not excessive backlash in the drive line. You could buy the accumulator valve assembly for this gearbox which will give an almost silent engagement.

[Paringa]

Fair enough.

 

The accumulator and another soft-shift for the PRM are knocking on for £350 - Perhaps i can put up with it...

[Dav and Pen]

I had this gearbox on a Sabre Perkins 130hp. Always used same as engine oil 15/40 must have done 1000’s of changes over 2400 engine hours and never noticed any “clunking” . Best gearbox I’ve ever had.

[Alan de Enfield]

I have a pair of PRM 500s on my Ford engines.

Not clunky or noisy.

 

Maybe there is a fault  ?

[fretman]

It's down to your clutch plate

[Boater Sam]

1 hour ago, fretman said:

It's down to your clutch       Drive plate

Corrected for you.

[fretman]

Thank you