Luke warm heat in B3030 cabbed tractor

[SRS]

Just recently the temperature here got down to about zero degrees and I went to use my cabbed Kubota B3030 HSDC tractor to plow snow. I noticed the temperature gauge stayed at the 'cold' level the whole time I was out plowing which was about 4 hours. The heat was warm but did not get the usual very hot like it did in prior years, of course it never got that cold in the past. I pulled the thermostat (rated 82 c or 180 degrees approximately) and put it in a pan of boiling water to test. It did not open until it was over 200+ degrees. I purchased a replacement thermostat and installed it and ran the tractor for just a short time in the garage. The gauge in the tractor rose just slightly above the 'cold' level but the heat was still luke warm. There was plenty of original anti-freeze in the 300 + hour tractor. Any thoughts, should I try to cover the radiator with cardboard? We don't normally get this cold so I guess I need to go out and see what kind of heat I get when the temps are in the 20's or 30's. And I do apologize to members who have open tractors that have no heat whatsoever. I know you can't feel too sorry for me-ha! Thanks for your input. Stanley

 

[SpudHauler]

Possibly air lock in the heater core.

But perhaps a plugged up heater core.

Suggest flushing the heater core if possible by unhooking the inlet and outlet hoses and forcing water through the heater making sure you are getting a good flow.

Drain your coolant out of the whole system and replace with fresh new stuff.

Only other possibility is the heat valve that turns the flow on/off is not opening fully.

On second thought, it's sounds like the whole tractor is not heating up enough. But you did replace the thermostat, strange.

You should never need to put cardboard in front of the rad at the temperatures you run. Up here in Canada at temperatures below 10 Fahrenheit we might then block up the radiator.

Cab heat is good this time of year.

Be interesting to hear what you find as the cure.

Good Luck.

 

[Tx Jim]

I'd block frt of radiator while closely monitoring temp gauge. If you'll notice big trucks utilize radiator curtains in below freezing temp's.

 

[SRS]

Thanks guys. I might try flushing the unit out completely whenever I get the chance. Also the heat valve ( I'm guessing controlled by the cable ) might not be opening/closing like it should. I think I might start first on removing the ceiling to see what's happening up there. It may take awhile but I'll post what happens. I appreciate your assistance. Stanley

 

[Tx Jim]

You're correct about a heater control cable if I looked at parts schematic correctly.

 

[SRS]

Tx Jim, the tractor has 300 + hours, original radiator fluid. I'm going to check the owner's manual and see what it says about when to change that. Regarding the cable whenever I push the lever all the way to the hot side it slowly creeps back just slightly. So that might be a good place to check to see if there is any spring in the cable that keeps it from staying all the way in the hot position. Thank you. Stanley

 

[SpudHauler]

If it's easy to get at, you could just unhook the cable and manually open the valve.

Give it a test and see what difference it makes.

 

[SRS]

Again thanks everyone for your suggestions. Here is what I did. On Monday I removed the new thermostat and completely flushed the radiator system out using Prestone radiator cleaner n flush. I used a lot of water to flush the system a few times. I then reinstalled the thermostat before adding the proper amount of coolant. I also removed the ceiling panel to see what was hidden there. I noticed the heat cable needed a slight adjustment so I took care of that. Since we got a substantial snow storm here on Tuesday I went out later in the evening during the height of the storm and I got plenty of heat, so much so that I never went above the 'low' speed on the blower. I plowed in a sweat shirt. What I've learned from this is I'll probably flush the radiator out yearly, it might be overkill but at least I'll know the system isn't collecting a lot of junk in there. Again thanks to everyone for their help, I truly appreciate it. Stanley