I recently bought a FA 645B loader. I can run the machine for an hour or more until the torque converter temp rises in to the red area. The engine has to be reved high to make the machine dig and work. I changed the trans fluid and filter. I put Dexron trans fluid back in. The old filter was relatively clean with no metal parts or shavings. I've been told the torque converter was bad. I was wondering how the machine reacts with the charge pump bad? How big a job is it to change the converter? I have ordered all the manuals from SSB Tractor. Thanks for your help in advance.
tootlems, sorry my late reply..have not been in the forum fore a while.
If the charge pump is bad the converter charge pressure will be low and you will have a slow moving and weak loader (converter slippage). Low main pressure will give low clutch apply pressure, causing converter slippage and overheating. In my case I lost all pressure and the loader would not move at all.
What pressure does your transmission pressure gauge shows?
I think it’s a big job to change the converter; you have to remove the engine before you can remove the converter from the loader.
Here’s a picture of the dismantled charge pump, as you can see the bearing in the driven gear is gone. As a result the charge pump was not able to build pressure or create vacuum to suck oil from the converter sump.
The reason for the charge pump damage is that the ball bearing for the accessory gear failed, (Pos no. 12) when the ball bearing failed it put all the stress on the small driven gear bearing.
As I understand this is a common problem on this transmission.
The ball bearing will now be replaced by a roller bearing.
