Ford 1715 FRUSTRATING Cavitation Problem

[Phil2004]

Hey all,
New here and new to tractors. Picked up an old Ford 1715 to help clear some land. Love it but the hydraulics are cavitating at high RPM.
Here is what I’ve done so far.

-replaced fluid with fluid from dealer
-replaced filter twice
-replaced filter housing/suction gasket
-replaced short rubber hose on suction side of flow line
-replaced all o-rings on flow lines
-rebuilt diverter valve/relief valve

Only thing I haven’t torn into is the loader valve.

HELP!!

 

[rScotty]

I see you have replaced the filter twice. Is yours one that has two filters? Most tractors of that vintage had one spin on filter and also a cleanable screen suction filter that is internal in the transmission.
It is usually accessed by removing a plate on the transmission - sometimes that plate is also where the suction line is mounted.

Not saying that is the problem....or even that yours has the typical two filters. But I am saying that your description of the problem exactly fits what happens when that cleanable filter needs cleaning.
rScotty

 

[ericm979]

Just curious, what are the symptoms of cavitation in this case?

I don't think the loader valve could cause it as it's on the pressure side.

 

[oldnslo]

Is the pump getting noisy at higher RPM or are you just seeing air bubbles in the reservoir?

 

[Jerry/MT]

Hey all,
New here and new to tractors. Picked up an old Ford 1715 to help clear some land. Love it but the hydraulics are cavitating at high RPM.
Here is what I’ve done so far.

-replaced fluid with fluid from dealer
-replaced filter twice
-replaced filter housing/suction gasket
-replaced short rubber hose on suction side of flow line
-replaced all o-rings on flow lines
-rebuilt diverter valve/relief valve

Only thing I haven’t torn into is the loader valve.

HELP!!

What tells you it is "cavitating"? Is it a high frequency noise? Could be air entrainment on the suction side. Do you have a suction screen? Is the suction line leak free?

 

[rScotty]

I see that the OP hasn't been back. Could be that he was simply using "cavitating" to mean that generally his loader isn't working well at high RPM.

I guess it could be a problem with the relief valve set too low - although I've never actually seen that happen.....

But the common cause of loader problems is low fluid flow to the pump on the suction side - either because of an air leak or because of that pesky cleanable filter hidden in the transmission housing of so many gear type compact tractors.

And sure enough, either one of those would cause the peculiar noises that we associate with cavitation in the high pressure pump. I wish he would describe those noises; you don't want cavitation at all, it erodes the metal of the pump and causes all kinds of problems.
rScotty

 

[Phil2004]

Sorry I haven’t been back guys. But yes the problem still persists. I am bringing the tractor into the shop this week to solve this problem once and for all, along with another new transmission problem that surfaced. I will post what I find, stay tuned….

 

[Phil2004]

Ok problem solved. After some more trial and error I found the solution and it’s really quite embarrassing.
I rebuilt the loader control valve as that was the last part of the hyd piping and valving that was untouched. But the problem persisted.
I checked the fluid level again and it was at the top side of full. So I slowly started to overfill the reservoir and the cavitation went away.
My 1715 has a 6.1 gallon hyd capacity but the pump produces over 9 GPM. Considering an industrial application will have 3x the max GPM oil capacity, the 1715 has a very small reservoir. So now I have to juggle overfilling the trans without submerging the shaft seal.