Plant Fitter
Senior Member
Old Cat 950. Don't know what year, but to give you an idea, it has air over hydraulic drum brakes, full air park brake, twist grip transmission control lever, and steering box type hydraulic steering.
Most of the time it works fine.
But occasionally, when it's cold, you start it up, let it warm up for a little bit, then when you try to drive off, it has no drive in any gear or any direction. After a while it comes good by itself. Then could go for ages before giving trouble again.
Oil level is good and the oil doesn't smell burnt or anything. Park brake works well and releases reliably.
I have pulled out the transmission screen, and apart from a few filings on the magnets it was pretty clean. I was surprised though, that the screen housing was empty. It's been sitting about a week since it was last driven, but I thought it would be full of oil? Is this normal? Seems a big job for the pump to draw oil all the way up through it if it starts off empty each time.
Any other thoughts about what it might be?
Most of the time it works fine.
But occasionally, when it's cold, you start it up, let it warm up for a little bit, then when you try to drive off, it has no drive in any gear or any direction. After a while it comes good by itself. Then could go for ages before giving trouble again.
Oil level is good and the oil doesn't smell burnt or anything. Park brake works well and releases reliably.
I have pulled out the transmission screen, and apart from a few filings on the magnets it was pretty clean. I was surprised though, that the screen housing was empty. It's been sitting about a week since it was last driven, but I thought it would be full of oil? Is this normal? Seems a big job for the pump to draw oil all the way up through it if it starts off empty each time.
Any other thoughts about what it might be?