CAT 943 Loader Hydrostat Questions

You current physical state bears some resemblance to your avatar I take it..?
I'm all right, on break until a week after New Year. So I don't have to worry.
Merry Xmas mate.

Cmark said:

It's a good job somebody's not hung over...

Click to expand...

Oh is that a O-ring seal on that pipe ? I didn’t pull it off yet but it’s leaking right at the fitting ? I thought it might be flared or something and it was cracked I will pull it off tomorrow

constman6 said:

Oh is that a O-ring seal on that pipe ? I didn’t pull it off yet but it’s leaking right at the fitting ? I thought it might be flared or something and it was cracked I will pull it off tomorrow

Click to expand...

It may be a JIC fitting or it may have a seal. Like I said, it depends on your transmission serial number.

Thanks, Cmark, for providing the Cat info...but the Cat people who dreamed up that abortion of a drawing should be shot with balls of their own shzt!!! Its a half a schematic and half a pictorial drawing and makes it hard as h*ck to follow and understand. Do you have any information on what the pressure taps should read and at what engine rpm?

There are some gems of info that we can glean from what we have for documents right now. Basicequipment, one of the pages mentions "Pressure taps" and it looks like they suggest they are on quick disconnects....I'm hoping they are lined up on a little panel somewhere, marked "A" to "Q". Are you able to do some pressure checks on some of those points? If you can, please let us know what you read at:

B: Charge pressure.
C: Servo supply pressure.
M: Charge pump pressure.

As I've noted to Cmark, the pressure readings really should be at some known engine rpm. But the charge pressure should be something over 345psi, the servo pressure should be 345psi +/-15 psi and the charge pressure should be 175psi +/-15psi.

Jon.

Here's a copy of the troubleshooting data sheet. It gives you the essential points. The important one for initial troubleshooting is the venturi differential pressure as that determines engine RPM which in turn determines pump output.

There hystats are marvels of engineering IMO and there's a lot going on at the same time.

Keep it simple I'd try and get three gauges set up start cold and see what's what. I'd suspect charge pressure is coming on slow at first thought. Could be scored charge pump having issue pulling prime.

Hi Cmark and Nige thank you for info I fixed that leak with adding a small o-ring on both ends of pipe looked like age has hardened the rubber in fitting .another question do you have a electrical schematic I’m trying to install new water temp and hystat temp gauges it’s driving me crazy some on cut some of the wires where the gauges go . I was tracing them out with a tracer but it don’t seem right . I just like seeing what’s going on before it’s to late I was going to run radiator over flow hose out in front of windshield so I could see it push water like nascar hahaha.

This is about the best I can do with a wiring schematic for the gauges.

Hi Cmark me again I have a host at line that is bad it goes to the drive motor the top line on the trans that has the steel tube on it to keep it bent ? When I change this do I have to bleed anything ? Or just add more trans oil ? Thanks

Hydrostatic line

Nothing to bleed. Just keep the oil level up and run at idle for a couple of minutes.
And be very careful not to let ANY dirt get into the open ports. Time spent cleaning before you remove the hose will be time well spent.

Thanks Cmark