Case Drain question

[woodlandfarms]

All the motors on my tractor (wheel and mower) have case drains. I just bought a new motor for a post hole digger (a rather large wheel motor) and it does not have a case drain.

So what is a case drain and should I send this bad boy back and get one with it?

Carl

 

[Rustyiron]

This is only a guess or an observation on my part but it seems that the high flow/rpm motors usually are the ones that I see the extra case drains on. I'm sure somebody will give you the answer here. I have a hyd post hole auger and it has only 2 lines to it.

 

[wdchyd]

Depending on the manufacturer and model, all motors don't have case drains.....motors that typically instantly reverse or have pressure in both directions at once usually have them.....

Some motors have higher pressure shaft sals and are internally drained to the return side downstream.....

I wouldn't be alarmed....use it..!!

 

[wdchyd]

A case drain alleviates (drains) the oil pressure from the inside portion of the shaft seal area....to keep shaft seal from blowing out.....

 

[EE_Bota]

I wouldn't be afraid of it at all if my only concern was the presence or absence of a case drain.

 

[Rustyiron]

A case drain alleviates (drains) the oil pressure from the inside portion of the shaft seal area....to keep shaft seal from blowing out.....

I knew I would learn something on this one!

 

[J_J]

Usually case drains are used with high capacity hyd motors. Primary purpose of case drains is to relieve pressure. If the pressure in the motor is allowed to remain high or above normal, then here is what will happen. I have case drains on my PT-1445.



Seal failure

High case pressure results in excessive load on the lip of the shaft seal. This causes the seal lip to wear a groove in the shaft, which eventually results in leakage past the seal. If case pressure exceeds the shaft seal's design limits, instantaneous failure can occur. The subsequent loss of oil from the case can result in damage through inadequate lubrication.

 

[wdchyd]

Other reasons for case drains (other than instant reversal) would be if several motors are hooked up in series......(the last one in a series run doesn't need case drain)

Also piston motors NEED case drains..!!

 

[woodlandfarms]

All good to know. Seems odd this is a 28 cu inch motor handling 3K psi and 18GPM to not have a case drain...

But hey, we will give it a try. Heavy bugger...