55 hours on BX1870 and overheating

Evan Williams II

New member

Equipment
BX1870
Mar 27, 2023
16
2
3
SW Pa, USA
Hello all. A few years ago, my father sold me his 2016 BX1870. he only had it a handful of years, but decided he needed something to attach a backhoe to, and that wasn't it. When I got it from him, it had 22 hours. I'm now at 55 hours. Last year, towards the end of the season, I noticed the temperature pushing up into the red while about 20 minutes into cutting by lawn. Stopped it, and it was boiling, and let it cool down. Took out the screen over the radiator, blew it out w/ air, there is no blockage.
I cleaned air filter location as a mouse had made a nest up there where you open the hood. That nest was removed prior to overheating. Tried it again and it does the same... runs nice and strong for 20 or so minutes while cutting w/ PTO, then temp starts to creep up again. I tested it running at full speed w/ PTO off, and it still gets hot. All fluids are at a correct level.
To me, this issue seemed to begin after I cleared out that mouse nest up on top where the hood opens, but I had had them there before and it wasn't an issue.
I bought a new thermostat that I haven't installed yet. Perhaps that will help.
I find this odd for a 55 hour unit. Anybody have a similar issue?
 
Last edited:

mcfarmall

Well-known member

Equipment
Kubota M5660SUHD, Farmall C
Sep 11, 2013
1,377
1,648
113
Kalamazoo, MI
Take out the radiator screen and blow compressed air across the radiator in the direction opposite of normal flow. You can try the garden hose as well. There may be very fine dust clogging the fins that made it through the coarse screen.

Check to be sure cooling system is full of antifreeze solution.
 
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Evan Williams II

New member

Equipment
BX1870
Mar 27, 2023
16
2
3
SW Pa, USA
Take out the radiator screen and blow compressed air across the radiator in the direction opposite of normal flow. You can try the garden hose as well. There may be very fine dust clogging the fins that made it through the coarse screen.

Check to be sure cooling system is full of antifreeze solution.
Thanks, forgot to add in original post the coolant was fine. updated. I did blow out the radiator area, but didn't use a water hose. Worth considering. Thanks.
 

GreensvilleJay

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Equipment
BX23-S,57 A-C D-14,58 A-C D-14, 57 A-C D-14,tiller,cults,Millcreek 25G spreader,
Apr 2, 2019
9,672
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Greensville,Ontario,Canada
full of coolant, rad's clear so....
hmm... maybe check / tighten the fab belt ?

THAT is the bane of my forklift ! It get a little loose, F/L will overheat AND not charge. I put a voltmeter on the dash which shows when the belt's loose......
 
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Evan Williams II

New member

Equipment
BX1870
Mar 27, 2023
16
2
3
SW Pa, USA
full of coolant, rad's clear so....
hmm... maybe check / tighten the fab belt ?

THAT is the bane of my forklift ! It get a little loose, F/L will overheat AND not charge. I put a voltmeter on the dash which shows when the belt's loose......
I thought about this as well. The belt/fan seem to be spinning just fine, but it doesn't seem really "tight"
 

GreensvilleJay

Well-known member

Equipment
BX23-S,57 A-C D-14,58 A-C D-14, 57 A-C D-14,tiller,cults,Millcreek 25G spreader,
Apr 2, 2019
9,672
3,919
113
Greensville,Ontario,Canada
T believe it should have about 1/2" deflection when you pus the mid point of the belt. Should be in the owner's manual, WSM and frankly really easy to test and tighten.
If it's proper I've run out of 'rabbits in my hat'.....
 

Evan Williams II

New member

Equipment
BX1870
Mar 27, 2023
16
2
3
SW Pa, USA
T believe it should have about 1/2" deflection when you pus the mid point of the belt. Should be in the owner's manual, WSM and frankly really easy to test and tighten.
If it's proper I've run out of 'rabbits in my hat'.....
Thank you, sir, I will try this later today. Whats your opinion on the thermostat replacement? To me, it seems worth a shot, though at 55 hours, that really shouldn't be bad.
 

GreensvilleJay

Well-known member

Equipment
BX23-S,57 A-C D-14,58 A-C D-14, 57 A-C D-14,tiller,cults,Millcreek 25G spreader,
Apr 2, 2019
9,672
3,919
113
Greensville,Ontario,Canada
It 'might' be 'sticking' though it's almost new(hrs) One idea is that it has so few hours,it's mechanically stuck, or corrosion ,again from sitting, has 'glued' the stat shut.
Usually a 'stuck' stat will allow the engine to heat up fast, then 'pop' open, HOT coolant goes into expansion tank and engine cools down fast. Cycle repeats again and again..... Old JEEP did that,in winter.
If you have an IR 'gun' you can get temperatures of the rad hoses and should be able to 'see' relative temperatures, or use your hands( be careful of course). hot top,cool btm...rads fine. hot-hot, rads plugged ( another possible problem....) may need cleaning...

Could be a good idea to buy a new stat and gasket anyway. If you order it this morning, then later today you'll find out it WAS a loose belt.....at least according to Mr. Murphy .
 

Grandad4

Active member

Equipment
1949 Farmall M, previously owned: L 4610, BX 2230
Apr 5, 2016
263
49
28
Greensboro, NC
If it has been used for mowing and the radiator has never been cleaned, that's a prime suspect. Fine debris may be pretty well embedded in there. Warm water and some detergent followed by gentle rinsing, no pressure washers.

Had to clean my BX rad several times each mowing season so it became a regular maintenance thing.
 

85Hokie

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Staff member
Lifetime Member

Equipment
BX-25D ,PTB. Under Armor, '90&'92-B7100HST's, '06 BX1850 FEL
Jul 13, 2013
10,271
2,104
113
Bedford - VA
If it has been used for mowing and the radiator has never been cleaned, that's a prime suspect. Fine debris may be pretty well embedded in there. Warm water and some detergent followed by gentle rinsing, no pressure washers.

Had to clean my BX rad several times each mowing season so it became a regular maintenance thing.

Clean and REAL clean are worlds apart. I would perhaps NOT use the water just yet. IF there is fine chafe in the fins - the water could compact them and make them harder to get out.

I would hit it with compressed air - from the inside out.

YOU can use a leaf blower too.

I would start the BX - and take a temperature reading at the top neck of the radiator, then take another reading at the bottom neck - THIS will tell you IF the radiator is at fault.
 

tinkerwitheverything

Active member

Equipment
bx2370-1
Jun 3, 2015
316
71
28
Manitoba
Seeing that there's a mouse nest on the top of the rad tells me just how often it gets service. Sorry but ant tractor mowing grass needs to have the rad cleaned regular. I mow with my BX 2370-1 plus use it for everything else loader work ,snowblowing etc:. I only have 1984 hrs on mine and have never had the gauge go over 2 bars. The tractor does get the screen and rad blown out every time it gets used for cutting grass . Again sorry but you do need to blow that rad and screen out on a regular basis.
 

Evan Williams II

New member

Equipment
BX1870
Mar 27, 2023
16
2
3
SW Pa, USA
Seeing that there's a mouse nest on the top of the rad tells me just how often it gets service. Sorry but ant tractor mowing grass needs to have the rad cleaned regular. I mow with my BX 2370-1 plus use it for everything else loader work ,snowblowing etc:. I only have 1984 hrs on mine and have never had the gauge go over 2 bars. The tractor does get the screen and rad blown out every time it gets used for cutting grass . Again sorry but you do need to blow that rad and screen out on a regular basis.
I clean it out often. I know how to service that. It's simple. The mouse nest, it is not due to lack of service. As mentioned, it has only 55 hours on it, and all services needed at that mark, I did. I can clean out the mouse nest on a Monday, park it, and it come Wednesday, they start another, so its not carelessness. maybe I need to put some more rodent killer out. It's just a very wooded area where I park it. Maybe I need to change parking spots as well.
 

Evan Williams II

New member

Equipment
BX1870
Mar 27, 2023
16
2
3
SW Pa, USA
Clean and REAL clean are worlds apart. I would perhaps NOT use the water just yet. IF there is fine chafe in the fins - the water could compact them and make them harder to get out.

I would hit it with compressed air - from the inside out.

YOU can use a leaf blower too.

I would start the BX - and take a temperature reading at the top neck of the radiator, then take another reading at the bottom neck - THIS will tell you IF the radiator is at fault.
OK. that was mentioned in an above reply. The temp part. Hot on top, cooler on bottom.
 

85Hokie

Moderator
Staff member
Lifetime Member

Equipment
BX-25D ,PTB. Under Armor, '90&'92-B7100HST's, '06 BX1850 FEL
Jul 13, 2013
10,271
2,104
113
Bedford - VA
I clean it out often. I know how to service that. It's simple. The mouse nest, it is not due to lack of service. As mentioned, it has only 55 hours on it, and all services needed at that mark, I did. I can clean out the mouse nest on a Monday, park it, and it come Wednesday, they start another, so its not carelessness. maybe I need to put some more rodent killer out. It's just a very wooded area where I park it. Maybe I need to change parking spots as well.

Start it and allow to heat up - see if the radiator is the problem - IT could be a stuck thermostat....maybe.

But finding out what the temp drop across the radiator is important = if there are high and real low - could a problem or maybe it is cool and cool .....

the nest may just be a coincident - but a infrared thermometer will tell you a lot about what is going on.
 

Evan Williams II

New member

Equipment
BX1870
Mar 27, 2023
16
2
3
SW Pa, USA
It 'might' be 'sticking' though it's almost new(hrs) One idea is that it has so few hours,it's mechanically stuck, or corrosion ,again from sitting, has 'glued' the stat shut.
Usually a 'stuck' stat will allow the engine to heat up fast, then 'pop' open, HOT coolant goes into expansion tank and engine cools down fast. Cycle repeats again and again..... Old JEEP did that,in winter.
If you have an IR 'gun' you can get temperatures of the rad hoses and should be able to 'see' relative temperatures, or use your hands( be careful of course). hot top,cool btm...rads fine. hot-hot, rads plugged ( another possible problem....) may need cleaning...

Could be a good idea to buy a new stat and gasket anyway. If you order it this morning, then later today you'll find out it WAS a loose belt.....at least according to Mr. Murphy .

The hoses might be a telltale sign. I tightened the fan belt. Really wasn't that bad, there was some slop. I had a new genuine Kubota thermostat, put that in (old one seemed fine). Really blew out the radiator/screen and started cutting grass. Did better it seemed today, but its not that warm out, so that might have been that. It then started creeping up, quicker w/ the PTO deck on and going up some hills cutting. Turned PTO off and continued driving it around and it seemed to settle on 4 bars on the guage, as opposed to the 5 bars w/ PTO on.
When stopped, I felt both top and bottom hoses.Top was really hot, and the bottom, though not as hot, it was still hot. I need to get an IR gun to check the actual temps... So that radiator might be the problem.
 

85Hokie

Moderator
Staff member
Lifetime Member

Equipment
BX-25D ,PTB. Under Armor, '90&'92-B7100HST's, '06 BX1850 FEL
Jul 13, 2013
10,271
2,104
113
Bedford - VA
The hoses might be a telltale sign. I tightened the fan belt. Really wasn't that bad, there was some slop. I had a new genuine Kubota thermostat, put that in (old one seemed fine). Really blew out the radiator/screen and started cutting grass. Did better it seemed today, but its not that warm out, so that might have been that. It then started creeping up, quicker w/ the PTO deck on and going up some hills cutting. Turned PTO off and continued driving it around and it seemed to settle on 4 bars on the guage, as opposed to the 5 bars w/ PTO on.
When stopped, I felt both top and bottom hoses.Top was really hot, and the bottom, though not as hot, it was still hot. I need to get an IR gun to check the actual temps... So that radiator might be the problem.
Get that IR gun - some of the best money you will spend!
 

RCW

Well-known member
Lifetime Member

Equipment
BX2360, FEL, MMM, BX2750D snowblower. 1953 Minneapolis Moline ZAU
Apr 28, 2013
8,282
3,868
113
Chenango County, NY
I don't think this is your issue, but food for thought - - Couple times my older BX2360 read HOT, when in fact it wasn't even up to operating temp yet.

I got my IR after mine read hot. Next time it read hot my upper rad hose was 135 +/- degrees or so with the IR thermo. Wasn't hot at all.

Little cleaning of the spade connector and dielectric grease on sending unit helped. Easy to get at, right on top of engine with a single wire connection.

When you do get your IR thermometer, take some actual temps, will help you characterize "HOT". Top/bottom hoses, radiator collar at top of tank/cap, etc. Maybe valve cover, block.
 

Evan Williams II

New member

Equipment
BX1870
Mar 27, 2023
16
2
3
SW Pa, USA
I don't think this is your issue, but food for thought - - Couple times my older BX2360 read HOT, when in fact it wasn't even up to operating temp yet.

I got my IR after mine read hot. Next time it read hot my upper rad hose was 135 +/- degrees or so with the IR thermo. Wasn't hot at all.

Little cleaning of the spade connector and dielectric grease on sending unit helped. Easy to get at, right on top of engine with a single wire connection.

When you do get your IR thermometer, take some actual temps, will help you characterize "HOT". Top/bottom hoses, radiator collar at top of tank/cap, etc. Maybe valve cover, block.
Ok. Do you know what the proper operation temps for the top and bottom hoses would be?