BX23 water pump questions

[tshep]

So, situation is BX/54 mower runs right up at orange with tall grass.
Recent work shows clear radiator (in and out), minimal internal rust, etc.
I believe I would NOT trust the water pump next.
I got tractor only a few years old.

Is it likely the original pump was a cast or formed (SS?) impeller?
Long term - should I seek OE or other water pump, formed or cast?

 

[dodge man]

I owned a BX2350 for about 10 years. They tend to run hot. Mine would get up near the red if cutting really tall grass. Before I even got the tractor home they told me that was the case. If just cutting my lawn it would get close to the red but not in it.

 

[rScotty]

If you drop down a gear in the tall grass will the tractor still get hot? I don't like to run my tractor hot; not enough margin for error.

 

[gengine]

Take the thermostat to Napa, they can probably match it up with another by size that is rated for lower temps, or just replace it with a new OE one to see if that fixes it. Water pump could also be an issue, but thermostats tend to be a lot cheaper and easier.

 

[JWR]

I owned a BX2350 for about 10 years. They tend to run hot. Mine would get up near the red if cutting really tall grass. Before I even got the tractor home they told me that was the case. If just cutting my lawn it would get close to the red but not in it.

Agree with Dodge Man. They do run on the hot side. I've owned 4 Kubotas and maintained 2 more. Every one of the BX ran almost to the red cutting heavy grass in hot weather. That said, I have run across several factors over the years: 1) Keeping the screen blown clear in front of the radiator is essential. They are very sensitive to that. 2) I could find absolutely NOTHING wrong with one that was running hot and even though the radiator "seemed" Ok replacing the radiator cured the issue. 3) One of them had a nick in the seat of the thermostat and brand new thermostats had no effect. Overflowing frequently of course. Finally found the nick and reamed it smooth to fix the issue. 4) The most elusive overheating issue among the several BX I've worked on was on a BX2200 that just would not "get OK" no matter what we did. After I sold it, the new owner (Mennonite mechanic) discovered the lower radiator hose was collapsing and lacked the normal spring inside to prevent that. He put in a spring and fixed that one too.
I have long believed that the BX 3 cylinder engines have too small a capacity water pump. I say that leaves it vulnerable to a long list of things that it should not be vulnerable to. Have not gone far enough to see if a water pump from a slightly larger 3 cyl diesel Kubota engine might have higher output and might fit.

 

[tshep]

I'm still beating on it.
Pump looked great inside, went back on.
Radiator at shop, guy said his chemicals pretty good.
I'm real suspicious now of that un-sprung lower hose.

 

[rScotty]

I'm still beating on it.
Pump looked great inside, went back on.
Radiator at shop, guy said his chemicals pretty good.
I'm real suspicious now of that un-sprung lower hose.

I'd sure check that hose, or better yet just replace it with one having the internal spring.

The other place that can cause overheating is where the fan shroud attaches to the radiator.

Sometimes there is an air gap there which allows the fan to draw air in from the sides of the shroud instead of being pulled in through the radiator fins. The cure is to seal the gap with automotive weatherstripping.
luck,
rScotty

 

[diesel85]

My BX2200 can get hot if I'm doing heavy (mostly during the spring) mowing with the MMM. It's the only implement I see this happen on.

A few years ago now, I mowed a little over 5 acres of 2-4' tall grasses with a 62" flail mower and it was running fine. Just a tick above the middle mark.

Otherwise, the needle stays right in the middle doing anything else after it's fully warmed up.

I know it's not anything with the MMM (bearings/gearbox) because I've been though it like a fine tooth comb. Very fluent about these Kubota MMM decks.

I need to try a 60" or 72" RFM and see if it produces the same results.

The only thing I don't like about the BX series machines is the reverse engine layout.

 

[Pinecrest]

So, situation is BX/54 mower runs right up at orange with tall grass.
Recent work shows clear radiator (in and out), minimal internal rust, etc.
I believe I would NOT trust the water pump next.
I got tractor only a few years old.

Is it likely the original pump was a cast or formed (SS?) impeller?
Long term - should I seek OE or other water pump, formed or cast?

I had a BX24 when it ran Hot I would need to tighten the fan belt. About every two years I would need to replace it as it was worn out. After replacing it would run in range as long as I kept the belt tight. The first time I replaced it it was a Learning Experience as the belt was driven by the drive shaft. The third time I changed it I was a Pro.

 

[Fxfymn413]

My BX2660 will get hot if I don't keep the radiator clean. Even with the screen in place dirt still clogs the radiator so I need to wash it out a couple of times a year.