TC29D overheating air restriction?

[barbqranch]

My TC29D has started overheating lately after 15 minutes or so of brush hogging. After starting temperature gauge rises normally to green range. Then, it will often cycle up and down an eighth inch or so for a while, then keep raising to red, at which point I drive back in. Checked radiator (when cold, at 2000 rpm) and no bubbles. Front of radiator mostly clear, liquid full. Changed water pump a year ago, no overheating till recently.

Air filter canister has a rubber intake nozzle that extends over radiator. It is partly collapsed going over radiator, and I am wondering if this might be the problem, and is there any problem with removing the "over the radiator" extension to see if that helps.

Haven't changed the air filter yet, will do so soon. It looks pretty much clean.
Thanks.

 

[Inspector507]

Have you cleaned the fins on the radiator out? Sounds like it may be clogged up.

 

[jimmysisson]

Bouncing needle may mean t stat is sticky. 7 yrs old could be getting crusted up.
Jim

 

[barbqranch]

Mowed again yesterday. In 5 minutes it was up to temp. Then for 5 minutes or so, temp went up and down. Then started climbing slowly to red. Got to mow for 20 minutes total.

Checked radiator. 90% clear, both before and after running. Outside temperature was about 65 degrees.

Looking at the photo in the posting about hyro cooler failure, his TC40 has a round tube that looks to be the air input. Mine is round into the air cleaner, but flattened oval over the radiator. Maybe flattened down to 3/4 size or so, I can't see it when the hood is down. Do you think it would be a problem to remove it for a while to see if that is the problem? It would still leave the air cleaner, but it would be getting air off the top of the engine.

 

[V1Rotate]

My TC29 has that same flatened out intake as yours, and I've had no problems with it. Couple of things to check, is the radiator screen clear? Fan belt tight? You might have a malfunctioning temp gauge, if you get one of those infrared thermometer guns (about 20 bucks at Home Depot) you can check the actual temperature of the engine while it is running.

 

[boomer1025]

I'd replace the thermostat & wash/spray out the radiator core from the back side with a garden hose.

 

[RickB]

Is it running hot, or is the gauge reading off? Could be either. Check radiator top tank or upper hose with a cheap non-contact infrared thermometer while the gauge is running in or near the red and report back. This site has many "overheating" threads where the OP's are too stubborn to actually check the coolant temperature before buying thermostats, water pumps, etc.
A restricted intake won't cause overheating and running the tractor without an air filter is a poor idea.

 

[barbqranch]

I just bought the non-contact thermometer from Harbor Freight, and will soon try it. The radiator is pretty clean, and I have hosed it out as much as possible front and back (with a cold engine).

Also, I am not thinking of running it without the air filter, just without the hose assy. that brings air from in front of the radiator to the filter housing.

Any suggestions as to what the thermometer should read "when in the green?"

 

[V1Rotate]

Around 190 degrees is normal. With your infrared themometer check the tempurature at the thermostat housing on the top of the engine, that should be the hottest part of the engine except for the exhaust manifolld.

 

[barbqranch]

Just finished my mowing, the last heavy work for a while. When done, it was at the top of the green almost in the red. Shut it off, and measured temperature at top of radiator w/ infrared thermometer. 205 degrees. I am guessing a thermostat is the next try? Running in 65 degree weather it should have cooling to spare, and most of the radiator was still clean when done.