Coolant not circulating

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Springer1

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My bobcat has run hot since the day i got it. I took the cap off the radiator and it doesnt appear that the coolant is circulating at all, it just sits there and vibrates with the engine shake. Should I start with a new thermostat, or just go ahead and replace water pump also. Is there another way to test this to see where the problem lays ?? Where would I get a thermostat for the V1702. I see the pumps around the net, but never the stat. Thanks
 

Tazza

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Start with changing the thermostat for sure, these can get stuck closed. Your dealer can sell you one or even a kubota dealer can. If it still runs hot it may be your radiator or water pump. Worst case, you can actually remove the thermostat as a temp. fix.
One way to check it to feel if the hose just above the water pump that goes back to the radiator should get hot. If so, you are getting water flow.
 

Tazza

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Start with changing the thermostat for sure, these can get stuck closed. Your dealer can sell you one or even a kubota dealer can. If it still runs hot it may be your radiator or water pump. Worst case, you can actually remove the thermostat as a temp. fix.
One way to check it to feel if the hose just above the water pump that goes back to the radiator should get hot. If so, you are getting water flow.
Be careful not to let the engine get too hot, these engines crack heads if they get too warm! just be careful.
 

Springer1

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thanks man !!
Ok took hose of top of thermo housing. The thermo appears to be partially open. I crank the bobcat over and it pumps coolant out of the thermo housing. So im assuming the pump is functioning ? I put the thermostat in very cold water and very hot water and it did nothing. What do you think ?
 

Tazza

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Ok took hose of top of thermo housing. The thermo appears to be partially open. I crank the bobcat over and it pumps coolant out of the thermo housing. So im assuming the pump is functioning ? I put the thermostat in very cold water and very hot water and it did nothing. What do you think ?
It sounds dead.
If you put the thermostat in boiling water it should open up. Its really hard to say what sate the water pump is in as you can't easily check pressure. They have a cast iron impeller that would take a lot to rust out!. I'd change the thermostat and see how it goes. If it still runs warm then start checking the radiator.
With the coolant drained it wouldn't hurt to hook up the garden hose to the radiator and give it a bit of a flush. Also, i would remove the inspection covers and check the oil cooler and radiator to see if they are clear. When the get clogged with dirt they don't cool very well.
If you are really worried about the water pump, you can remove it and if its ok put it back with red silicone or any instant gasket. That way you know its ok.
 

siduramaxde

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It sounds dead.
If you put the thermostat in boiling water it should open up. Its really hard to say what sate the water pump is in as you can't easily check pressure. They have a cast iron impeller that would take a lot to rust out!. I'd change the thermostat and see how it goes. If it still runs warm then start checking the radiator.
With the coolant drained it wouldn't hurt to hook up the garden hose to the radiator and give it a bit of a flush. Also, i would remove the inspection covers and check the oil cooler and radiator to see if they are clear. When the get clogged with dirt they don't cool very well.
If you are really worried about the water pump, you can remove it and if its ok put it back with red silicone or any instant gasket. That way you know its ok.
I wouldn't even go through the trouble of removing the t-stat without putting a new one in it's place. T-stats are cheap and make sure you put it in the correct way.
 

Springer1

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I wouldn't even go through the trouble of removing the t-stat without putting a new one in it's place. T-stats are cheap and make sure you put it in the correct way.
Thanks guys, got my new thermostat in the mail today, will flush the system and re-install this weekend !
 

Springer1

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Thanks guys, got my new thermostat in the mail today, will flush the system and re-install this weekend !
Gott'er done, and im all but sure the pump is operating sufficiently. The top hose gets hot and the radiator is warm on the intake side and cool on the return side. The lower return hose is also cool. Im now questioning the sensor and temp gauge. Those cant be too hard to change eh? Now i gotta find em.
 

Tazza

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Gott'er done, and im all but sure the pump is operating sufficiently. The top hose gets hot and the radiator is warm on the intake side and cool on the return side. The lower return hose is also cool. Im now questioning the sensor and temp gauge. Those cant be too hard to change eh? Now i gotta find em.
Thats normal, hot on the left cool on the right.
The sender is in the head on the right, rite next to the alternator just below where the hose connects. Its easy to replace.
 
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