powershift or hydrastatic drive

[retired]

I have a 1994 cat 939 crawler loader and I don't know if it is apowershift or a hydrastatic drive

Thanks

 

[Tyler d4c]

It is a hydrastatic

 

[Welder Dave]

Not good to ask multiple times. I answered in your other thread. It's most likely a powershift. Later models were hydrostat.

 

[Tyler d4c]

Not good to ask multiple times. I answered in your other thread. It's most likely a powershift. Later models were hydrostat.

931 935 where powershift 939 where hydro.

 

[retired]

You are gracious to answer me. Frankly, I am so dumb when it comes to computers that I get confused. It kept asking me to do things and I am never sure if I am doing the right thing or if I have not done what I am suppose to. As you can see I received two different answers. Can one tell by just looking in the cab because of the way the foot pedals or hand controls are configured , whether it is a powershift or a hydrestatic drive ? I have a left and right foot pedal for steering and a middle pedal called a park brake. My hand controls on the left consist of two levers. One operates the gas, the other controls the forward motion and the back motion - 3 forward and 3 back.
Again thank you all for your answers. I have lots of questions about this machine. I am impressed by the work it can do even though the operator is very limited. I wish one of you guys was my neighbor.

 

[retired]

I see from tyler d4c I just got an answer.

Thanks to everyone.

 

[Tyler d4c]

You are gracious to answer me. Frankly, I am so dumb when it comes to computers that I get confused. It kept asking me to do things and I am never sure if I am doing the right thing or if I have not done what I am suppose to. As you can see I received two different answers. Can one tell by just looking in the cab because of the way the foot pedals or hand controls are configured , whether it is a powershift or a hydrestatic drive ? I have a left and right foot pedal for steering and a middle pedal called a park brake. My hand controls on the left consist of two levers. One operates the gas, the other controls the forward motion and the back motion - 3 forward and 3 back.
Again thank you all for your answers. I have lots of questions about this machine. I am impressed by the work it can do even though the operator is very limited. I wish one of you guys was my neighbor.

If the final drive has a planetary drive on it its a hydrostatic. If it looks like the photo it's a power shift.
Either may also have a weight installed here if unshore a photo of witch would help. By your description of the controls sounds like its a power shift. A machine serial number would be helpful

 

[Nige]

AFAIK all 943 track loaders are hydrostatic. As Tyler says a Serial Number would confirm it 100%.

 

[retired]

9GL00290

Thanks for your interest

 

[Nige]

9GL00290

Thanks for your interest

Then it is a powershift transmission with a torque converter.

 

[Tyler d4c]

Not good to ask multiple times. I answered in your other thread. It's most likely a powershift. Later models were hydrostat.

My apologies WD my information is wrong

 

[Welder Dave]

931 935 where powershift 939 where hydro.

939C were hydrostat. Early 939 were powershift. Look on the net. I thought they were all hydrostat too. They weren't big sellers.

 

[Tyler d4c]

939C were hydrostat. Early 939 were powershift. Look on the net. I thought they were all hydrostat too. They weren't big sellers.

I seen that I thought all the 939 where hydros myself

 

[retired]

Another mystery I have concerning the hydraulic fluid refill tube. Since I had a leaking hose - very small - I looked at the glass and it seemed low therefore, I attempted to unscrew the cap and anyway I had a dickens of a time getting it to unscrew. I had turned the machine off, put on the park brake and added a little pressure on the bucket when I lowered it. It says to put a little downward pressure when parking. I had some maintaince done on the machine about 2 years ago - fluids drained, etc. well all of a sudden the cap flies of and some fluid flies out. I looked at the glass and it seemed well above the haveway mark. Did the repairman put too much hydraulic fluid in it.
Thanks.

 

[Tyler d4c]

It's possible it's over filled the tank will have pressure on it as they are not venter to atmosphere. Something like 7 psi the check valve keeps in the tank

 

[retired]

Thanks that was probably the problem

 

[Welder Dave]

You need to slowly loosen the cap and you'll hear air escaping. Down pressure on the bucket shouldn't affect the hyd. tank but if the cap was taken off quickly might blow some oil out. I just put the bucket on the ground. It doesn't need down pressure and after sitting for an hour or more will likely relax the down pressure anyway. I figure it's easier on the seals to not leave a lot of pressure on the cylinders.

 

[retired]

Thanks for the information. I am mostly brain dead when itcomes to this thing, but gradually am finding out stuff thanks to you guys. Although,I am 81, I am hoping to stick around awhile to finish my projicts.

 

[Welder Dave]

Just take your time and be aware of everything and everyone around you. If pushing tree's over, be especially alert because tree's are unpredictable and could fall back on you.

 

[retired]

Thanks