High water teperature in Bobcat 743

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miszka01

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Jan 27, 2007
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I have a problem. I don't know what's going on. When I work about hour temperature of water is very high. I changed plug ( cork), move out thermostat and problem is again. When I stop engine I hear gurgle in water cooler. Maybe gasket of head ? Sombody knows what is hepend. Thanks
 

Tazza

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Are your covers in place in the engine bay that directs the air up and through the radiator?
Check coolant level.
The gurgle, does this happen all the time? if so, it could be the head gasket or worse still, the head if you let the temperature get too high.
The senders can go bad, it may be giving you a wrong reading.
Replace the thermostat.
You may need to get the radiator flushed.
Check the radiator fins for junk, air should be able to pass through easily.
There are a lot of things that could be causing the problem. Start with the simple, then move to the more difficult/expensive.
 

miszka01

Member
Joined
Jan 27, 2007
Messages
13
Are your covers in place in the engine bay that directs the air up and through the radiator?
Check coolant level.
The gurgle, does this happen all the time? if so, it could be the head gasket or worse still, the head if you let the temperature get too high.
The senders can go bad, it may be giving you a wrong reading.
Replace the thermostat.
You may need to get the radiator flushed.
Check the radiator fins for junk, air should be able to pass through easily.
There are a lot of things that could be causing the problem. Start with the simple, then move to the more difficult/expensive.
Thanks 1. no covers 2. Coolant level is OK 3.The gurgles are all the time when engine is work very hard and at top speed 4. I removed out thermostat 5. I"m going to get the radiator flushed tooday
 

Tazza

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16,697
Are your covers in place in the engine bay that directs the air up and through the radiator?
Check coolant level.
The gurgle, does this happen all the time? if so, it could be the head gasket or worse still, the head if you let the temperature get too high.
The senders can go bad, it may be giving you a wrong reading.
Replace the thermostat.
You may need to get the radiator flushed.
Check the radiator fins for junk, air should be able to pass through easily.
There are a lot of things that could be causing the problem. Start with the simple, then move to the more difficult/expensive.
If its gurgling after a run you may have loose head bolts too. If you are mechanically able, it would pay to nip them up just to be sure. If you need torque settings and instructions just yell. I don't believe this is causing the heat problem but still you should get it fixed up.
After the radiator flush and test i'd swap the thermostat. If it still gets hot, i'd check the water pump. It could still be as simple as a bad sender or gauge.
After a re-build my 743 gurgled. It so happens i wasn't told to re-torque the head after its initial run. The head gasket compressed and the exhaust gas was escaping between the gasket and the water galleries. I tensioned the head and its been great since.
Remember, Kubota engines do NOT like getting hot. When they get too hot they crack heads, don't try and get away with it if it is over heating, a new head is over 1K, you don't need that expense.
Let us know how you go..
 

Fishfiles

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Feb 8, 2007
Messages
1,698
Before I'd pull the radiator I would do two things if your have access to the tools , first thing would be to use an exhaust gas detector , very inexpensive from say Napa , you take off the radiator cap and place the clear tube with a rubber funnel shaped end which sticks into the radiator opening , you put in the blue fluid and run the engine if the color changes to yellow you have a blown gasket or crack in head or block , second would be a radiator pressure tester and atttach to the rad. and pump it to the specs. on the cap , which I would presume is O.E.M. or at least the same pressure rating , start the engine and note if pressure is building in the Rad. , the pressure cap rating is important as water boils at 212 degree , but for every pound of pressure you put the water under it increases the boil point by 2 degrees , so if you have say a 10 lb cap the water won't boil till 212 plus 20 which is 232 degrees , also the rad.pressure tester will test the cap to see if it will hold the rated spec. , you may have to take out the covers that is behind/top of the motor and pressure wash the fins externally as it is probally blocked up with dirt and restricting air flow , you can see the flow of water once the thermostat opens by looking down the open rad. cap , another thing oI have seen is operator will hit the travel lever with his leg and engage the aux hydraulics causing the machine to get hot , just a few ideas good luck
 

miszka01

Member
Joined
Jan 27, 2007
Messages
13
Before I'd pull the radiator I would do two things if your have access to the tools , first thing would be to use an exhaust gas detector , very inexpensive from say Napa , you take off the radiator cap and place the clear tube with a rubber funnel shaped end which sticks into the radiator opening , you put in the blue fluid and run the engine if the color changes to yellow you have a blown gasket or crack in head or block , second would be a radiator pressure tester and atttach to the rad. and pump it to the specs. on the cap , which I would presume is O.E.M. or at least the same pressure rating , start the engine and note if pressure is building in the Rad. , the pressure cap rating is important as water boils at 212 degree , but for every pound of pressure you put the water under it increases the boil point by 2 degrees , so if you have say a 10 lb cap the water won't boil till 212 plus 20 which is 232 degrees , also the rad.pressure tester will test the cap to see if it will hold the rated spec. , you may have to take out the covers that is behind/top of the motor and pressure wash the fins externally as it is probally blocked up with dirt and restricting air flow , you can see the flow of water once the thermostat opens by looking down the open rad. cap , another thing oI have seen is operator will hit the travel lever with his leg and engage the aux hydraulics causing the machine to get hot , just a few ideas good luck
Thanks for everybody. I removed radiator and it was very derty, doust. I washed by karcher and now is OK. I tought the hed gasket was broken. Best regards
 

Tazza

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Thanks for everybody. I removed radiator and it was very derty, doust. I washed by karcher and now is OK. I tought the hed gasket was broken. Best regards
Glad its ok, if it still gurgles, i'd still check the head bolt tensions just to be sure.They should be 55-58 Ft Lbs and valve clear acne should be .007” - .009”
I'd check one or 2 and if loose i'd tighten them all. If you need it, i can scan in bolt tension orders for you..
 
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