Bobcat 642 With kent motor/ford. Maybe over heating issue

[shane77]

I bought this bad boy used. Pretty decent shape. Ran it around for 20min and everything seem to work fine. So I bought it

Then I put her to work and she started to run warm. Not in the but darn close. Seeing the radiator was original and after flushing I decided to replace it and clean the hydraulic radiator to while at it. Thought that would do the trick. But after about 45min to hour she creeps up close to the red line again. With my laser heat gun I test the lines. I'm reading 140 to 160 degrees on the out put side of radiator and from engine to the radiator I'm getting reading from 170 to 198 being the thermostat area is almost 200 degree.
What is the operating temp of these machines? I can not seem to find this info. I went to pull thermostat and it was missing.
Going to put a new water pump on her to make sure that is good to. I have not pulled plugs yet to scope and see if the head gasket is bad. She's a bit cold blooded to start but once up to halfway I usually can shut off the choke. My local Bobcat dealer not much help. The guy seems stoned all the time and was a pain to get updated auxiliary fitting that should have been simple. Any help would be appreciated

Thanks

 

[foton]

replace with a the thermostat,I think 180 degree F should be good.

 

[foton]

and when you get it look to see if there is a small triangle or hole in the thermostat door it will help vent out air out of the system on that first start up. if it is not there a 1/16 drill will do the job.

 

[shane77]

I have a thermostat to put in it but it seems to be missing the spring that is used to keep it in place. Do you by chance have the part number for that? Been having a hard time trying to source one.

 

[shane77]

I bought this bad boy used. Pretty decent shape. Ran it around for 20min and everything seem to work fine. So I bought it

Then I put her to work and she started to run warm. Not in the but darn close. Seeing the radiator was original and after flushing I decided to replace it and clean the hydraulic radiator to while at it. Thought that would do the trick. But after about 45min to hour she creeps up close to the red line again. With my laser heat gun I test the lines. I'm reading 140 to 160 degrees on the out put side of radiator and from engine to the radiator I'm getting reading from 170 to 198 being the thermostat area is almost 200 degree.
What is the operating temp of these machines? I can not seem to find this info. I went to pull thermostat and it was missing.
Going to put a new water pump on her to make sure that is good to. I have not pulled plugs yet to scope and see if the head gasket is bad. She's a bit cold blooded to start but once up to halfway I usually can shut off the choke. My local Bobcat dealer not much help. The guy seems stoned all the time and was a pain to get updated auxiliary fitting that should have been simple. Any help would be appreciated

Thanks

Just an update after finding a ankowlageable Bobcat dealer. This units actual thermostat is 190 degrees. Actual running temps range from 170 degrees-220. With normal running in the190s. Dealer said on very hot days you can expect to see 200s-210. But you don't want to see much more than that. Once you start pushing the 220 degrees that's when you see warped heads. And expect to on hot days to give the machine breaks to cool down. This was all Info from the dealership. I ALSO ran into a general use thermostat that's offset brass. That opens at 180degrees it is a general use thermostat made for all the 600 series motor is what I was told. You will see these sold on line for all the models. Figured I better update this post sense this was the most frustrating info for me to find.... hope this helps other keep these old dogs working. The 642 was my first machine I learned on when I was 18 years old at cement company and she was a good machine. So I was excited to be able to buy one for home use 30 years later lol may be old but still good machine's.

 

[ZekeSkyree]

Just an update after finding a ankowlageable Bobcat dealer. This units actual thermostat is 190 degrees. Actual running temps range from 170 degrees-220. With normal running in the190s. Dealer said on very hot days you can expect to see 200s-210. But you don't want to see much more than that. Once you start pushing the 220 degrees that's when you see warped heads. And expect to on hot days to give the machine breaks to cool down. This was all Info from the dealership. I ALSO ran into a general use thermostat that's offset brass. That opens at 180degrees it is a general use thermostat made for all the 600 series motor is what I was told. You will see these sold on line for all the models. Figured I better update this post sense this was the most frustrating info for me to find.... hope this helps other keep these old dogs working. The 642 was my first machine I learned on when I was 18 years old at cement company and she was a good machine. So I was excited to be able to buy one for home use 30 years later lol may be old but still good machine's.

I have a 642 and it had the same problem. Pull both the hydraulic and motor radiators and make sure they are clean. Might want to flush them after reinstalling. Pretty easy job and good piece of mind

 

[shane77]

I have a 642 and it had the same problem. Pull both the hydraulic and motor radiators and make sure they are clean. Might want to flush them after reinstalling. Pretty easy job and good piece of mind

I ran into the heat gauge sending unit was also the wrong one making my gauge read higher than it should..ST cloud bobcat knew thier stuff and got me the correct parts. the last time I ran it was running at 160 degrees on a 3 mile drive to the gas station. Never went higher. It was 71 degrees outside. After replacing the radiator I ordered a new hydraulic radiator too. That I will replace in the spring. With winter coming on I figured I better get the correct thermostat for her. I don't want it running to cool now with MN winters coming on. Hate to have the motor sludge up. Relieved to know operating temps.... now on to installing my heater and cab cover and hooking up the plow.... do you know what sweeper model works best with a 642?