Hey fellas, new guy here....have some issues.

[melly-mel]

i have a mid 90's 853c bobcat. i think the waterpump is bad.....i put a new thermostat, flushed radiator, and after all this i open cap when i started it and had my son rev the engin up and down to see if the coolent was moving in the radiator.....nothing seemed any different when he revved it. fluid stayed at same level, and did not seem to move. i dont have any leaks near the pump that i see, but after all i did i am stumped. does this sound like the water pump? if so where can i order the parts online? local shop is terrible, and i would rather not deal with them. thanks alot.

 

[OldMachinist]

Did you allow it to warm up and open the thermostat before looking for flow?
Does it overheat?
What engine do you have?

 

[melly-mel]

Did you allow it to warm up and open the thermostat before looking for flow?
Does it overheat?
What engine do you have?

i did let it warm up.....it slowly climbed up to near overheat but than i shut it down. it never got cooler, just a steady climb over like 25 or 30 minutes and when it got near the red i shut it down..... if i let it go i think it would overheat....i think the motor is an isuzu. the way i see it is its wither the pump or (please no) the head gasket.

 

[mrfixitpaul]

i did let it warm up.....it slowly climbed up to near overheat but than i shut it down. it never got cooler, just a steady climb over like 25 or 30 minutes and when it got near the red i shut it down..... if i let it go i think it would overheat....i think the motor is an isuzu. the way i see it is its wither the pump or (please no) the head gasket.

I haven't seen any problems with the Isuzu head gaskets in working on 843 & 853's but it could be. First I'd make sure the fan drive and water pump belts are tight and that the radiator is clean on the outside. Then I'd check the temp with a thermometer and see if the guage is accurate or giving false info. Next maybe pull the waterpump...?

 

[melly-mel]

I haven't seen any problems with the Isuzu head gaskets in working on 843 & 853's but it could be. First I'd make sure the fan drive and water pump belts are tight and that the radiator is clean on the outside. Then I'd check the temp with a thermometer and see if the guage is accurate or giving false info. Next maybe pull the waterpump...?

temp gauge is brand new, belt is tight as well. after all the coolant flush, new thermostat, belt check, new coolant, im lost.

 

[melly-mel]

temp gauge is brand new, belt is tight as well. after all the coolant flush, new thermostat, belt check, new coolant, im lost.

how do i tell for sure if its an isuzu? its grimy and old so i am not 100 pct, but that is what i was told when i bought it.

 

[skidsteer.ca]

how do i tell for sure if its an isuzu? its grimy and old so i am not 100 pct, but that is what i was told when i bought it.

I believe it is cast in the top of the valve cover, for that model Bobcat it should br a Isuzu 4JB1 PK3
Shown below

If you pull the air filter canister out, you will find a pipe going from the thermostat housing around the operators left end of the engine and into the water jacket. The water will circulate through this pipe while the thermostat is closed. With the engine running check to see if its the same temp as the rest of the engine. If its taking it 30 min to get over heated it must be putting some water through the rad and cooling a bit.
Now would be a good time to invest a $50 in a infrared thermometer.
Can you feel any heat in the rad? If the water pump in new I can't see that not working. The only thing that ever goes wrong with one is the bearing and seals. They always pump. Boil the you new thermostat in a pot of water to confirm it opens. Also does it have a tiny vent hole so that any air trapped in the block from draining the engine can vent to the rad while refilling the system.
Also if you gauge is electric, a poor ground or other wire connection can make it read falsely, I'd confirm the temp it is indicating by some other means.
Oh and for engine parts not available at your local parts place, go to Isuzu directly, my water pump was $156 there and $250 ish at bobcat.
Ken

 

[melly-mel]

I believe it is cast in the top of the valve cover, for that model Bobcat it should br a Isuzu 4JB1 PK3
Shown below

If you pull the air filter canister out, you will find a pipe going from the thermostat housing around the operators left end of the engine and into the water jacket. The water will circulate through this pipe while the thermostat is closed. With the engine running check to see if its the same temp as the rest of the engine. If its taking it 30 min to get over heated it must be putting some water through the rad and cooling a bit.
Now would be a good time to invest a $50 in a infrared thermometer.
Can you feel any heat in the rad? If the water pump in new I can't see that not working. The only thing that ever goes wrong with one is the bearing and seals. They always pump. Boil the you new thermostat in a pot of water to confirm it opens. Also does it have a tiny vent hole so that any air trapped in the block from draining the engine can vent to the rad while refilling the system.
Also if you gauge is electric, a poor ground or other wire connection can make it read falsely, I'd confirm the temp it is indicating by some other means.
Oh and for engine parts not available at your local parts place, go to Isuzu directly, my water pump was $156 there and $250 ish at bobcat.
Ken

the water pump is not new. thermostat is, temp gauge is, and i flushed radiator, and put in new coolent. checked belts, and it is still getting hot.

 

[melly-mel]

the water pump is not new. thermostat is, temp gauge is, and i flushed radiator, and put in new coolent. checked belts, and it is still getting hot.

radiator hoses are getting hot as is the radiator and coolent. but after 30 minutes i think everything will get hot with no flow, or if the head gasket is shot and the vapors are heating the fluid?

 

[skidsteer.ca]

radiator hoses are getting hot as is the radiator and coolent. but after 30 minutes i think everything will get hot with no flow, or if the head gasket is shot and the vapors are heating the fluid?

If the head gasket was shot the compression vapours leaking into the cooling system would be blowing the rad cap off. Often coolant gets discolored with oily grey combustion gases. Hard to miss. Or you smell antifreeze in the exhaust. Motor runs poorly.
The pipe I mention going around the engine is isloated from the block, the only way it warms as fast as the motor is if water is being pumped through it. Pulling the air filter is a 10 minute job. I'm betting your guage is incorrect. Can't see it getting hot just sitting there running.
The water pump is easy to pull also, you could check the impellor for blockage from rust and scale, but easier to check the retun pipe first.
Ken

 

[melly-mel]

If the head gasket was shot the compression vapours leaking into the cooling system would be blowing the rad cap off. Often coolant gets discolored with oily grey combustion gases. Hard to miss. Or you smell antifreeze in the exhaust. Motor runs poorly.
The pipe I mention going around the engine is isloated from the block, the only way it warms as fast as the motor is if water is being pumped through it. Pulling the air filter is a 10 minute job. I'm betting your guage is incorrect. Can't see it getting hot just sitting there running.
The water pump is easy to pull also, you could check the impellor for blockage from rust and scale, but easier to check the retun pipe first.
Ken

ok, heres what i did....pulled the thermostat, coolent started to get hot boiling over into the overflow when machine ran for 30 minutes. after i shut it off the rad was burping ,and seemed sloshing around with coolent, and it was still going into the overflow. put thermostat back in,and the machine got hot again, but no coolent going into the overflow this time. not sure what to make of this. i am lost. old coolent was old, but did not seem oily, or fuel smelling. i also replaced rad. cap as well, and no help still. i mean i am lost....water pump, head gasket are the only things left i figure. i mean thermostat is installed spring down correct?

 

[melly-mel]

ok, heres what i did....pulled the thermostat, coolent started to get hot boiling over into the overflow when machine ran for 30 minutes. after i shut it off the rad was burping ,and seemed sloshing around with coolent, and it was still going into the overflow. put thermostat back in,and the machine got hot again, but no coolent going into the overflow this time. not sure what to make of this. i am lost. old coolent was old, but did not seem oily, or fuel smelling. i also replaced rad. cap as well, and no help still. i mean i am lost....water pump, head gasket are the only things left i figure. i mean thermostat is installed spring down correct?

also, motor seems to be running fine. not smoking or anything. seems to have normal power.

 

[skidsteer.ca]

ok, heres what i did....pulled the thermostat, coolent started to get hot boiling over into the overflow when machine ran for 30 minutes. after i shut it off the rad was burping ,and seemed sloshing around with coolent, and it was still going into the overflow. put thermostat back in,and the machine got hot again, but no coolent going into the overflow this time. not sure what to make of this. i am lost. old coolent was old, but did not seem oily, or fuel smelling. i also replaced rad. cap as well, and no help still. i mean i am lost....water pump, head gasket are the only things left i figure. i mean thermostat is installed spring down correct?

When did this problem start, did you buy it this way? or owned it and all of a sudden you're overheating??
Did the new thermostat look like the old one you removed? Some have a valve built into them to route the coolant through the return pipe back to the bottom of the engine when they are closed and of course to the rad when they are open. I can't remember if there was anything special about mine of if it was just a common disc style t stat. Maybe call Isuzu and see if they can sugest anything. Part came from Bobcat or a auto parts place? Spring down is right.
You can't see any bubbles coming up in the rad when the engine is running, does it gurgle only when its getting real hot, or the whole time it runs? The fan is whistling good air volume out the side vents?
There is a reason, just have to find it.
Ken

 

[melly-mel]

When did this problem start, did you buy it this way? or owned it and all of a sudden you're overheating??
Did the new thermostat look like the old one you removed? Some have a valve built into them to route the coolant through the return pipe back to the bottom of the engine when they are closed and of course to the rad when they are open. I can't remember if there was anything special about mine of if it was just a common disc style t stat. Maybe call Isuzu and see if they can sugest anything. Part came from Bobcat or a auto parts place? Spring down is right.
You can't see any bubbles coming up in the rad when the engine is running, does it gurgle only when its getting real hot, or the whole time it runs? The fan is whistling good air volume out the side vents?
There is a reason, just have to find it.
Ken

it has sat a while, and i am just starting to use it again. thermostat is new from bobcat dealer. gave him serial number. gurgles when it gets hot, not when at normal temp. seems like air is coming out well from vents. don't see any bubbles in rad. wehn i looked it just seems to be stagnent only movement was from vibration of motor.

 

[skidsteer.ca]

it has sat a while, and i am just starting to use it again. thermostat is new from bobcat dealer. gave him serial number. gurgles when it gets hot, not when at normal temp. seems like air is coming out well from vents. don't see any bubbles in rad. wehn i looked it just seems to be stagnent only movement was from vibration of motor.

Don't sound like head gasket. No bubbles, until it starts to boil from the heat, no steam out exhaust, no oily coolant.
Check that pipe, see if it heats even with the block, if it not circulating it will stay considerably colder. Failing that pull the water pump and look at the impellor. Believe it has a o ring for a gasket.
A temp gun would be helpfull, see if rad is as warm as engine, any hot spots on the engine. Maybe some fresh perspectives here shortly.
Ken

 

[melly-mel]

Don't sound like head gasket. No bubbles, until it starts to boil from the heat, no steam out exhaust, no oily coolant.
Check that pipe, see if it heats even with the block, if it not circulating it will stay considerably colder. Failing that pull the water pump and look at the impellor. Believe it has a o ring for a gasket.
A temp gun would be helpfull, see if rad is as warm as engine, any hot spots on the engine. Maybe some fresh perspectives here shortly.
Ken

ok....i will pull the pump tomorrow. i really hope that it is that, and not the head. for the new pump is it possible to get it online? not thinking i have any isuzu dealers close. hope it is in fact an isuzu. thanks fo your time, and help. much appreciated

 

[skidsteer.ca]

ok....i will pull the pump tomorrow. i really hope that it is that, and not the head. for the new pump is it possible to get it online? not thinking i have any isuzu dealers close. hope it is in fact an isuzu. thanks fo your time, and help. much appreciated

If it looks like the picture, it is Isuzu, Bobcat used Kubota in the 700 series loaders. (has flywheel/drive belt on left side) and Deutz in the 863 873 models during these years. Deutz is oil cooled so thats ruled out.
Not sure if the water pump can be sourced aftermarket or not. I just called a Isuzu dealer with the numbers off the block and they shipped out the correct pump. Go to Isuzu website and look up their dealer locations. Still unless the impellor is clogged up or corroded away, can't see how it could fail. At least it will be obvious if those problems are the case here. Try ebay and the engine rebuilder too. Those motors are real common in truck reefers I'm told.
Your welcome, hope you get it sorted out.
Ken

 

[melly-mel]

If it looks like the picture, it is Isuzu, Bobcat used Kubota in the 700 series loaders. (has flywheel/drive belt on left side) and Deutz in the 863 873 models during these years. Deutz is oil cooled so thats ruled out.
Not sure if the water pump can be sourced aftermarket or not. I just called a Isuzu dealer with the numbers off the block and they shipped out the correct pump. Go to Isuzu website and look up their dealer locations. Still unless the impellor is clogged up or corroded away, can't see how it could fail. At least it will be obvious if those problems are the case here. Try ebay and the engine rebuilder too. Those motors are real common in truck reefers I'm told.
Your welcome, hope you get it sorted out.
Ken

looks exactly like motor in pic, but mine is much dirtier...lol. only 2500 orig hrs, but it's a grease pit. got it for dirt cheap to use at my house from a friend who got from someone who owed his money. thing purrs like a kitten. i just hope i can figure this out.

 

[melly-mel]

looks exactly like motor in pic, but mine is much dirtier...lol. only 2500 orig hrs, but it's a grease pit. got it for dirt cheap to use at my house from a friend who got from someone who owed his money. thing purrs like a kitten. i just hope i can figure this out.

think i got it figured. i was checking the belt again, and i realized that the fan belt tensioner is super easy to move by hand. the spring is not letting the fan belt stay tight on the pully, and i think it's slipping. the tension spring seems shot since i am able to pull it up, and remove the belt by hand. so i need that, and a new belt i am hoping.