Kubota tractor overheating when fan replaced to electric. (Kubota G1900S (D722))

[GreensvilleJay]

It'd be best to remove both fan and shroud,then 'trim' the shroud to properly fit the fan. I know shroud might be a 'pain' to remove from tractor but 'on the bench' is the only SAFE way to cut/hack/grind the shroud. The trick is to NOT be in a rush ! Take a little off at a time, check for fit and repeat.'Sneak' up to the final fit. You need the air to flow through the fan cleanly.
I used a heavy(dense) A/C dbl sided foam tape to fill the gap I needed on an old Willy pickup refurb. Filling that 1/4" gap made a HUGE difference.
This is one job where patience and thinking ahead will pay off. Hopefully you won't have to remove/reinstall more than a few times.....BTDT

 

[ve9aa]

4 pages of replies on how NOT to "fix" a lawnmower.
I don't know if it's a record or what to make of it all.

??

 

[GreensvilleJay]

it'll be 6 or 7 by the end of the day !
Seems Buffalo's being dumped on ,'lake effect', hehehe...
BTW Never understood the need for a diesel powerd $$$$$ lawn mower....
When asked if I wanted the MMM for my BX23S I said I can buy 4-5 beater riders for the price and I'm still using the 20 year old Cub cadet that I paid $220 for....

 

[lmichael]

Actually I don't recall posting or seeing anything what you'd call "uncivil" hell I've been watching this because I had actually been thinking about this myself for my G2160. Not because I intend to make mods to it. I love the music that little diesel makes as it is. But, just as kind of an improvement. But, it looks like Kubota knew what they were doing when they designed the cooling system

 

[ve9aa]

I have a much older TG1860 (diesel) lawn mower/lawn tractor and I would not trade it for 2 brand new gassers.

Why?

Much better fuel economy (this is not so much about $$, but there is no need to stop and refuel mid-mow.....it's like the Energizer bunny and keeps going and going.

Less noise with my diesel. The gassers are all louder

Produces a tiny bit of smoke, which may/maynot help keep flies away?

REliable. Very little in the way of repairs in the 17/18 yrs I've owned it. The Cheapie Walmart (or whatever) gassers all wear out , break down and whatever.

And the #1 reason why I love my TG1860 is the suspension for the rider. I have not seen another lawn mower here in NB, like it. The whole rear 1/3 of the rider station/seat/floorboard is on 2 "minibike" shocks which gives a great ride for the driver.

WOuld I ever put an electric fan on it because it was slightly overheating? Nope! I would figure out what was causing the overheating.
Dandelion fluff in the rad screen?
Worn water pump?
Poor mix as cooling fluid?
Bad fuel?
Loose fan belt?
Failing water pump?
Failing head gasket?
CRacked block or head?
Something else I haven't thought of (I'm no expert)

 

[GreensvilleJay]

HAM, I understand your reply... dang gassers are loud, though not enough to drown out the gaggle of HD goofballs that speed down my road....oh well, snow's on the ground so they 'magically' disappear for a few months !

overheating...you forgot one, kind obvious....
blocked radiator.. the tubes can get 'plugged up' with 'junk' over the years, slowly reduces coolant flow, when enough tubes get plugged THEN someone takes notice......

Reminds me, have to cover up 75% of my 'dandelion fluff screen'. Going to be a LOT easier than the 2 1/2 HOURS to put a tube into a rider's front tire yesterday (yeah ORIGINAL 'SEARS' ) tire finally started leaking

 

[fried1765]

it'll be 6 or 7 by the end of the day !
Seems Buffalo's being dumped on ,'lake effect', hehehe...
BTW Never understood the need for a diesel powerd $$$$$ lawn mower....
When asked if I wanted the MMM for my BX23S I said I can buy 4-5 beater riders for the price and I'm still using the 20 year old Cub cadet that I paid $220 for....

I used "riders" for 50+ years.
Gas or diesel "rider".......never again!
My SCAG Kawasaki gas zero turn is the cats Axx!

 

[Henro]

Just had a strange thought. Might prove something, might not.

Could you cover the front of the radiator with a sheet of paper or something, on a cold start, and then see what flow you sense the fan pulling?

This might indicate that air flow is NOT passing through the radiator, if you still seem to sense adequate air flow at the exit side of the electric fan.

Just something I would probably do...

 

[GeoHorn]

Unnecessary Amateur modification…and even that was screwed up with that hack-job on the shroud.
Sorry to be so harsh w/criticism…but OP…you’re working in the wrong direction I think.

 

[GreensvilleJay]

curious..
to those that HAVE added a turbo, did you have to replace the rad with a bigger one ? If so ,how much bigger and HOW did you 'showhoen' it into the tractor ?
Also with the added HP/torque did you need to upgrade the drivetrain at all ?

 

[dvcochran]

No it's most definitely pulling air out the back, the way it originally did.

Honestly, I have never seen an engine mount that way. Seeing it now makes me wonder if there are restrictions between the radiator and the steering wheel. Could some sort of directional louver be missing?
When I added my electric fan, I left the engine side alone and added the fan on the front of the radiator pushing air through. Made quite a difference on the A/C side of things. But I was not having engine cooling issues.

 

[jacoBiceps]

4 pages of replies on how NOT to "fix" a lawnmower.
I don't know if it's a record or what to make of it all.

??

Seriously!! I haven't gotten any further than I was before I posted this.

 

[jacoBiceps]

curious..
to those that HAVE added a turbo, did you have to replace the rad with a bigger one ? If so ,how much bigger and HOW did you 'showhoen' it into the tractor ?
Also with the added HP/torque did you need to upgrade the drivetrain at all ?

I really would love to replace the radiator with a bigger, high flow, slim rad, but there is no way I could fit it while still being able to close the hood.

 

[jacoBiceps]

Honestly, I have never seen an engine mount that way. Seeing it now makes me wonder if there are restrictions between the radiator and the steering wheel. Could some sort of directional louver be missing?
When I added my electric fan, I left the engine side alone and added the fan on the front of the radiator pushing air through. Made quite a difference on the A/C side of things. But I was not having engine cooling issues.

You are the only person on here who has made me think. That is a really good point. As far as I know, there was no directional venting on the opposite side of the radiator. I don't think I can fit the electric fan on the back of the rad as the steering shaft is about an inch away from the rad.

 

[jacoBiceps]

curious..
to those that HAVE added a turbo, did you have to replace the rad with a bigger one ? If so ,how much bigger and HOW did you 'showhoen' it into the tractor ?
Also with the added HP/torque did you need to upgrade the drivetrain at all ?

That's my biggest worry going forward with power mods. I'm not looking to make huge power. The next weakest link would either be the head gasket or the driveshaft.

 

[jacoBiceps]

Unnecessary Amateur modification…and even that was screwed up with that hack-job on the shroud.
Sorry to be so harsh w/criticism…but OP…you’re working in the wrong direction I think.

Steer me in the right direction please.

 

[jacoBiceps]

I have a much older TG1860 (diesel) lawn mower/lawn tractor and I would not trade it for 2 brand new gassers.

Why?

Much better fuel economy (this is not so much about $$, but there is no need to stop and refuel mid-mow.....it's like the Energizer bunny and keeps going and going.

Less noise with my diesel. The gassers are all louder

Produces a tiny bit of smoke, which may/maynot help keep flies away?

REliable. Very little in the way of repairs in the 17/18 yrs I've owned it. The Cheapie Walmart (or whatever) gassers all wear out , break down and whatever.

And the #1 reason why I love my TG1860 is the suspension for the rider. I have not seen another lawn mower here in NB, like it. The whole rear 1/3 of the rider station/seat/floorboard is on 2 "minibike" shocks which gives a great ride for the driver.

WOuld I ever put an electric fan on it because it was slightly overheating? Nope! I would figure out what was causing the overheating.
Dandelion fluff in the rad screen?
Worn water pump?
Poor mix as cooling fluid?
Bad fuel?
Loose fan belt?
Failing water pump?
Failing head gasket?
CRacked block or head?
Something else I haven't thought of (I'm no expert)

This is great tips. I never thought of some of them. I suspected the water pump, but what could go wrong with a mechanical water pump? It's just a pulley with a impeller right? A loose fan belt is a great suspect as it does tend to slip a lot. As for bad fuel, I don't know how to check that other than draining the old fuel and refilling. I don't run a rad screen as I just make sure to blow it off good with my blower after every cut.

 

[jacoBiceps]

It'd be best to remove both fan and shroud,then 'trim' the shroud to properly fit the fan. I know shroud might be a 'pain' to remove from tractor but 'on the bench' is the only SAFE way to cut/hack/grind the shroud. The trick is to NOT be in a rush ! Take a little off at a time, check for fit and repeat.'Sneak' up to the final fit. You need the air to flow through the fan cleanly.
I used a heavy(dense) A/C dbl sided foam tape to fill the gap I needed on an old Willy pickup refurb. Filling that 1/4" gap made a HUGE difference.
This is one job where patience and thinking ahead will pay off. Hopefully you won't have to remove/reinstall more than a few times.....BTDT

Awesome advice. Thank you so much!!

 

[GeoHorn]

Steer me in the right direction please.

Return it to original configuration…. make any other “HP” mods you wish to make…THEN see if you need addt’l cooling…. but I doubt you will need any.

 

[dvcochran]

You are the only person on here who has made me think. That is a really good point. As far as I know, there was no directional venting on the opposite side of the radiator. I don't think I can fit the electric fan on the back of the rad as the steering shaft is about an inch away from the rad.

I assume there are covers off so how/where does the radiator draw air from? I don't like all the electrical right in the path of the radiator. How is a person supposed to properly clean it?
Chaff can really be deceiving, and the newer style radiators are a PITA to clean. Get some coil cleaner and wash it well then carefully blow it out with an air hose. Then do it again, Then, run it hard to make sure the radiator is dry before putting it back in the dust.
Like others have said, I would put everything back to square one after a thorough cleaning and see if it makes a difference.
As far as water pumps, they can get weaker from worn vanes and can even go bad. But usually, you can hear or feel a bad water pump.
Get back to square one and start with the simple stuff.