D7H, 79Z 1753.
Problem has been ongoing since I bought the tractor about 2 years ago.
The problem has stayed very steady and persistent.
On a cool day the trans will heat up to 210 with the motor running 170. It heats up slowly taking an hour or so if pushing hard, in less than 2 hours it heats up if working easy.
It slowly gets to 220-230 on 80-90 degree days bringing the motor up to 180's. In 90-100 degree days it's a problem with it getting 230's.
The trans won't cool done with the tractor sitting still, med throttle or low throttle. It might cool off 10 degrees or so but never cools to the motor temp.
Things I've done:
The injector pump was remaned by cat when I first got the dozer.
Last year I took off the trans cooler and cleaned it, some blockage. Pump preasure was like 20 psi low-put a cat reman on.
Checked temps gauge with a temp gun.
This winter I had the torque rebuilt, all new hoses on the tranny and torque, new radiator, cleaned the tranny cooler-no blockage.
No change.
Did more preasure checks. Everything checked out ok except the pump drive lubrication. This port is on the front of flywheel housing, same side as trans cooler. it checked 30psi low idle (40psi +- 10) 45 psi high idle (70 +- 10 is the spec).
Anyone have ideas?
Also changed filter and oil, checked screens which are clean. Old oil smelled burnt.
Trans holds, shifts just like it should. Brakes and steering clutches are excellent.
Tractor will coast on a slope.
Problem has been ongoing since I bought the tractor about 2 years ago.
The problem has stayed very steady and persistent.
On a cool day the trans will heat up to 210 with the motor running 170. It heats up slowly taking an hour or so if pushing hard, in less than 2 hours it heats up if working easy.
It slowly gets to 220-230 on 80-90 degree days bringing the motor up to 180's. In 90-100 degree days it's a problem with it getting 230's.
The trans won't cool done with the tractor sitting still, med throttle or low throttle. It might cool off 10 degrees or so but never cools to the motor temp.
Things I've done:
The injector pump was remaned by cat when I first got the dozer.
Last year I took off the trans cooler and cleaned it, some blockage. Pump preasure was like 20 psi low-put a cat reman on.
Checked temps gauge with a temp gun.
This winter I had the torque rebuilt, all new hoses on the tranny and torque, new radiator, cleaned the tranny cooler-no blockage.
No change.
Did more preasure checks. Everything checked out ok except the pump drive lubrication. This port is on the front of flywheel housing, same side as trans cooler. it checked 30psi low idle (40psi +- 10) 45 psi high idle (70 +- 10 is the spec).
Anyone have ideas?
Also changed filter and oil, checked screens which are clean. Old oil smelled burnt.
Trans holds, shifts just like it should. Brakes and steering clutches are excellent.
Tractor will coast on a slope.
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