B7200 running hot

[Paul Allwood]

After mowing for about 20 minutes a week ago I noticed steam coming from the radiator overflow tube.

The outside of the radiator and the screen in front of it are all clear.

Looking in the top of the radiator, the only cores I can see appear to be mostly full of rust. Not sure what the rest of the cores are like but probably no reason to think they would be any better.

I've removed the radiator - hoping to pick up a new one tomorrow.

I took the water pump off but it looks new so it will be going back on. I did notice that the nuts securing the pump were only just right - don't know if it was leaking.

Also removed and tested the thermostat. It's marked as 82 deg C. Starts moving just as the water starts boiling then opens fully. They're cheap, so I'll replace it anyway.

The fan and the shroud look ok and the belt was tight, might fit a new belt anyway.

I'm also planning on fitting an overflow bottle unless someone has a house reason not to ??

When flushing water through the engine, is there any particular inlet that's better to feed the hose into ?

It's there anything else to check or change while I'm at it ?

Thanks all.

 

[GreensvilleJay]

Was always told flush 'backwards' tot he normal flow of water, supposed to clean out the block better. Looking at the condition, probably want to flush the block 2-3 times. Should be some good chemicals today to remove the junk, just follow the instructions.

 

[Runs With Scissors]

I would check/clean/replace the air filter too.

 

[Paul Allwood]

Was always told flush 'backwards' tot he normal flow of water, supposed to clean out the block better. Looking at the condition, probably want to flush the block 2-3 times. Should be some good chemicals today to remove the junk, just follow the instructions.

Thanks, I'll see what I can find

 

[Paul Allwood]

I would check/clean/replace the air filter too.

Thanks, will add it to the list for tomorrow

 

[Bee-Positive]

Being a 35+ year old tractor, and looking at your picture, it might be cheap peace-of-mind to replace the hoses while your at it. JM2C.

 

[mdhughes]

Back in to day when I was younger I did work for my cousin rodding radiators. Take the top tank off and run rods down each tube and then solder the tank back on. Don't know if there are any radiator shops that do that kind of work anymore.

 

[GeoHorn]

I offer the advice to AVOID CHEMICALS.

I’m 3/4’s of a century old…and I have a LOT of experience from my youth of using cooling-system chemicals…which convinced me the Chemicals are BAD. Each and Every time I used them…. I lost the water pump shortly thereafter.

If you plan to keep that water pump…don’t run chemicals thru it.

If you plan to run chemicals…. then …as soon as you finish flushing all those chemicals OUT…. Install a New Water Pump with the proper coolant (anti-freeze).

It’s also a good time to send that radiator out to a proper ”radiator shop” to have it cleaned (boiled) and pressure-tested / repaired before re-installation.

Trust me on this.

 

[Paul Allwood]

Being a 35+ year old tractor, and looking at your picture, it might be cheap peace-of-mind to replace the hoses while your at it. JM2C.

Thanks

 

[Paul Allwood]

I offer the advice to AVOID CHEMICALS.

I’m 3/4’s of a century old…and I have a LOT of experience from my youth of using cooling-system chemicals…which convinced me the Chemicals are BAD. Each and Every time I used them…. I lost the water pump shortly thereafter.

If you plan to keep that water pump…don’t run chemicals thru it.

If you plan to run chemicals…. then …as soon as you finish flushing all those chemicals OUT…. Install a New Water Pump with the proper coolant (anti-freeze).

It’s also a good time to send that radiator out to a proper ”radiator shop” to have it cleaned (boiled) and pressure-tested / repaired before re-installation.

Trust me on this.

Thanks. Would your suggestion be to flush with water, reassemble, then fill with coolant ?

 

[N3BP]

You might also consider installing a temperature gauge. It's a good indicator when your radiator screen starts to clog. My 7200HST runs 160-180 degrees mowing depending on ambient temperature.

 

[GeoHorn]

Thanks. Would your suggestion be to flush with water, reassemble, then fill with coolant ?

It’s a subjective matter to judge how much rust/corrosion and radiator blockage you might have. But flushing with plain water is a good idea, and again, consider sending the radiator out to a radiator shop.

 

[North Idaho Wolfman]

You can also use vinegar, but you really should not need to go to that extreme.

Did you do a bubble test?
Bubbles in the radiator is an indication of head gasket issue or a cracked head.

 

[Paul Allwood]

It’s a subjective matter to judge how much rust/corrosion and radiator blockage you might have. But flushing with plain water is a good idea, and again, consider sending the radiator out to a radiator shop.

I think I'll just replace the radiator

 

[Paul Allwood]

You can also use vinegar, but you really should not need to go to that extreme.

Did you do a bubble test?
Bubbles in the radiator is an indication of head gasket issue or a cracked head.

Thanks. There are no bubbles, thankfully

 

[Russell King]

I think I'll just replace the radiator

I think you will be shocked at the cost (if it is even available).

Good luck with it

 

[Paul Allwood]

I think you will be shocked at the cost (if it is even available).

Good luck with it

From my local (Australian) Kubota dealer it's about $780. From Friday Parts it's $330 but doesn't match exactly....next question.

 

[Paul Allwood]

I need some help identifying a house in the pics below.

The hose at the red arrow in the first pic connects to the bottom of the radiator alongside the main bottom radiator hose. With the drain valve screed in it seems there would only be a small flow allowed. What does this hose do ? Obviously it was put there for a reason, how important is it ?

The next 2 pics show my current blocked radiator. The red arrow shows where the above house connects.

The next pic shows a B7200D radiator from Friday Parts - there's no connection for this hose at the bottom of the radiator.

My tractor is a B7200HSTD - is the hose related to the HST version ?

Short of getting my radiator pulled apart and rodded, can anyone shed any light on the above or suggest a source for a matching radiator ?

 

[Paul Allwood]

Update - I just found what looks like a matching radiator on eBay. It doesn't list the B7200HSTD, but the connections and dimensions on other pics appear to match. Good enough for me, just hope it matches the pics when it arrives.

I'm still interested in the house I asked about above if anyone knows.

Thanks.

 

[North Idaho Wolfman]

That hose is a burp hose.
It keeps the block from trapping a bubble in it and causing a hot spot.
It was eliminated on later models with a redesign of the thermostat housing.