Bobcat 963T overheat

[chrisb]

Hi guys, looking for some help with an overheat issue I have been dealing with. The 963t has a perkins diesel. A friend and brought it to me with this issue. I was told the thermostat was replaced a month ago so I started with the water pump. I made sure the pump was working and even removed the thermostat to make sure that wasnt the problem. I bled the bleeder at the thermostat housing and ran the engine with the radiator cap off to make sure I got all the air out. Oh, I also blew the radiator out with a nozzle with a 1/2 inch hose. It appeared the water was circulating with the cap off but once I put the cap on and ran the machine for 20 to 30 minutes the guage went to the yellow. After shutting the machine the down I could hear the coolant boiling in the return hose. My conclusion is the radiator has to be blocked. This is my friends machine and I dont want him to spend money needlessly, so I just wanted to check with the someone more experienced. Thanks

 

[Tazza]

Its very possible that the radiator is blocked up, the only real way to know is to get it serviced. Its not a bad idea to get it done, that's the one thing you don't want to fail on you causing it to take the engine with it.

 

[chrisb]

Its very possible that the radiator is blocked up, the only real way to know is to get it serviced. Its not a bad idea to get it done, that's the one thing you don't want to fail on you causing it to take the engine with it.

Yeah, so if anyone cares to know. I pulled the radiator and had it serviced and while installing the radiator I realized the return hose was collapsed on the backside. I got a new hose and a new cap for the radiator and it still got hot. I spoke to a service guy at bobcat and he said the hydraulic fan has a coil that allows the fan to spin at a faster speed once the coolant reaches a certain temp. That is the only thing that has not been changed. I pulled the coil and the plastic was cracked and it appeared to be burnt. I also did a block test with the coolant to make sure there were no exhaust gases in the radiator so I can rule out a cracked head or head gasket. The test checked good. The only thing I can see is the fan not pulling enough air to cool the radiator. If anyone has any other thoughts please let me know.

 

[Tazza]

Yeah, so if anyone cares to know. I pulled the radiator and had it serviced and while installing the radiator I realized the return hose was collapsed on the backside. I got a new hose and a new cap for the radiator and it still got hot. I spoke to a service guy at bobcat and he said the hydraulic fan has a coil that allows the fan to spin at a faster speed once the coolant reaches a certain temp. That is the only thing that has not been changed. I pulled the coil and the plastic was cracked and it appeared to be burnt. I also did a block test with the coolant to make sure there were no exhaust gases in the radiator so I can rule out a cracked head or head gasket. The test checked good. The only thing I can see is the fan not pulling enough air to cool the radiator. If anyone has any other thoughts please let me know.

Its really the only thing left..... Good to hear the exhaust gas test showed that the engine is in good shape.
I never knew these machines ran a hydraulic cooling fan.