Mowing Kubota diesel overheating.

[4570Man]

I’m pretty sure that’s not his problem, he would notice a cylinder dropping out also. The problem occurs when a injector over fuels a cylinder and causes it to get hot.

The engine runs good, the exhaust is clean, the power output is good, I’m confident the water pump is good. I don’t think there’s anything wrong with the engine.

 

[sandman2234]

View attachment 702614

It must be dirty, as I can't see thru any of the fins in this picture, lol!!
David from jax

 

[Midniteoyl]

I took the radiator out and cleaned it. It looks pretty clean but on close inspection there was quite a bit of trash in it. I’ve cleaned it, put a new fan belt on, new thermostat in and I’ve got some chemical radiator flush to go in after I put it back together.

Straighten as many fins as you can as well while its out.

 

[ROUSTABOUT]

It seems to be circulating otherwise the radiator wouldn’t be hot. At least that’s my logic.

No, the impellers corrode off water pumps. They will kind of circulate. If you had no water pump at all, the radiator would still get hot just from heat rising. Does it crank evenly? Any smoke?

 

[4570Man]

Today I removed and cleaned the radiator, which had a surprising amount of dirt in it, installed new thermostat, installed new fan belt, did a chemical flush and put everything back together. And it was running cool until a leak in the lower hose drained the radiator. But I think it’s working properly now.

 

[Williy]

Midniteoyl I know that in my car without anti-freeze
would over heat and with a 50/50 mix was OK! I
only use distilled water in radiator. So what are
you trying to tell me???

willy

 

[4570Man]

And I came to an accidentally discovery of why running straight water is a bad idea aside from corrosion problems. You can smell leaking antifreeze from a mile away. But with the water I had no indication it was leaking. It’s a rear engine so you’d never see it. Luckily it was a slow leak and the temperature gauge registered the rising temperature. But the temperature gauge requires coolant to work and if a catastrophic leak dumped the coolant you’d never know it before it was too late.

 

[4570Man]

No, the impellers corrode off water pumps. They will kind of circulate. If you had no water pump at all, the radiator would still get hot just from heat rising. Does it crank evenly? Any smoke?

If the radiator was cooling as designed but the coolant wasn’t circulating as designed the radiator would never get much above ambient temperature. The radiator is designed to loose heat rapidly so what little heat it would collect from non circulating coolant would easily be cooled. You’d never get a 190 degree radiator which mine was with a bad water pump and functioning fan and radiator.

 

[Williy]

I read that the Brits say the aluminum & plastic
radiators are throw aways and some other
Brits said K-seal works great for fixing leaks

willy

 

[Hay Dude]

It must be dirty, as I can't see thru any of the fins in this picture, lol!!
David from jax

Ahhhh yeah that kind of obstruction will cause a wee bit of overheating lol
My tractor rads get a deep cleaning 1-2 times/year. Hay chaff and dust builds up to the point where any exterior obstruction on the hood causes temps to hit 200 and more.