[fjmg]

I am in the process of checking everything on a hydravac I had purchased and was going to drop off the impeller at a machine shop to check balance but they need to know the rpm of the impeller. Does anybody know the specs on the hyd. Motor so we can calculate rpm?

 

[Hydriv]

There is no such thing as a "fixed speed" for the impeller. It will spin at whatever RPM that all the variables will dictate.

As an example, the size of the hydraulic pump will vary from tractor to tractor as will the amount of wear on those pumps. The wear factor of the motor will also affect the RPM.

If they are looking for a maximum speed for the purposes of balancing, then 4000 RPM would be the target. If the impeller does not display any vibration from 0 to 4000 RPM, I'd say that they've got it covered.

 

[fjmg]

Thanks that is what I will tell them. I took a look on the John barnes/haldex site and all their motors of this approximate size listed a max of 4000 rpm and some were at 3600 so without the cu. In. of the original I can only guess the max rpm attained with this unit on a 1972 444.