Stuck Thermostat???

[TopK]

I need a sanity check - not sure if my pea brain is over-analyzing this one. I’m doing basic maintenance on the used BX2360 that I just bought (460 hrs). Followed the steps from this link to change the Coolant:

When I removed the bolt to drain the Block, hardly anything came out - just a little trickle. The video showed a ton of coolant coming out from the Block. Then, after I completed the change, I let it cool down to add more coolant (since it’s expected that the “heat cycle” would open up the thermostat and fill the Block). I didn’t have to top off the Radiator at all, just a very small amount in the overflow tank.

Could this be an indication of a stuck Thermostat? It appears that it should be relatively easy to remove and test it - I see from the KPAD diagram that it’s at the Block end of the Upper Radiator Hose.

Or, perhaps I didn’t let the Tractor get hot enough? Ran it close to 10 minutes, and the temp gauge was about midway between Bottom and HOT. I’ve hardly used the tractor, but when I have, the Temp gauge never got too Hot. Should I be concerned and go to the trouble of pulling the Thermostat to test it?

 

[TheOldHokie]

I need a sanity check - not sure if my pea brain is over-analyzing this one. I’m doing basic maintenance on the used BX2360 that I just bought (460 hrs). Followed the steps from this link to change the Coolant:

When I removed the bolt to drain the Block, hardly anything came out - just a little trickle. The video showed a ton of coolant coming out from the Block. Then, after I completed the change, I let it cool down to add more coolant (since it’s expected that the “heat cycle” would open up the thermostat and fill the Block). I didn’t have to top off the Radiator at all, just a very small amount in the overflow tank.

Could this be an indication of a stuck Thermostat? It appears that it should be relatively easy to remove and test it - I see from the KPAD diagram that it’s at the Block end of the Upper Radiator Hose.

Or, perhaps I didn’t let the Tractor get hot enough? Ran it close to 10 minutes, and the temp gauge was about midway between Bottom and HOT. I’ve hardly used the tractor, but when I have, the Temp gauge never got too Hot. Should I be concerned and go to the trouble of pulling the Thermostat to test it?

Unless the tractor overheats I wouldn't touch it. Get the engine up to operating temp , shut it off, check coolant level when safe to do so and top up as needed.

Dan

 

[GeoHorn]

The “trickle” may have been due to rust/sediment blocking the drain. A wire or screwdriver stuck into the hole might have cleared out the sediment and facilitated a quicker drain-time.

 

[TopK]

The “trickle” may have been due to rust/sediment blocking the drain. A wire or screwdriver stuck into the hole might have cleared out the sediment and facilitated a quicker drain-time.

Hmmm....it sure didn't seem to be blocked, but it may be worth investigating. Tell me if this is a proper approach - I'm thinking I can just remove the Block bolt again and use a wire to ensure there is no blockage. If I get more Coolant, than it proves your theory correct. If I don't get any, then I'm still puzzled by the lack of Coolant in the Block. I won't drain the Radiator again. I'll get it up to operating temp, shut down, cool off, and (hopefully) top off the Radiator - sound reasonable? The other part of me tends to agree with the first reply - "If it aint broke, don't fix it"! But, I'm just too curious at this point to give up.

 

[D2Cat]

If you have an infrared thermometer you can measure the top hose and the bottom hose to see how hot it is and how it is cooling. They're an inexpensive tool these days.

 

[cthomas]

Are you taking the radiator cap off when removing block drain? Therefore, the thermostat is holding vacuum. During the duramax block heater recall I was applying vacuum and swapping heaters with little coolant lost as the new duramax sucks to get full.

 

[North Idaho Wolfman]

None of what your explaining is a "stuck thermostat".
Pull the block drain plug, and pull the radiator cap and the radiator drain if equipped to drain the system.
The thermostats have a burp hole that eliminates the pocket of air getting stuck in the block.

 

[GreensvilleJay]

ct just beat me , need to remove rad cap. My BX23S only gets 1/3rd on the temp gauge,even when worked hard on hot days.

 

[TopK]

ct just beat me , need to remove rad cap. My BX23S only gets 1/3rd on the temp gauge,even when worked hard on hot days.

The Radiator Cap was off from the start. I also removed the plug near the Upper Hose like the video showed during refill.

 

[GreensvilleJay]

hmm NOT a vacuum problem, suspect 'crud' in the drain spigot/hole. My air compressor tank does that... 150# pressure and water doesn't flow out until I 'tease' the gorf with an awl...THEN it dribbles and finally flows out. Silly ,CHEAP design uses 1/4" valve and no easy way to plumb in a 3/8 or 1/2 ball valve...
great NOW I know what my morning 'project' is going to be......sigh..

 

[Vigo]

I also agree with just poking something through the block drain hole and seeing what happens. This is pretty common with block drains which are very rarely removed so whatever coats/blocks them on the inside has time to almost fossilize with all the heat cycles, turning into something that most be poked through or broken up to get it flowing again.

But in general removing block drains once in a while is a good thing just because it avoids the scenario where noone has moved it in 30 years and then im doing surgery trying to save an engine block from a stupid 30cent plug that has tried to become one with it.

 

[lmichael]

Yeah, first time I tried to open the block drain petcock on my G2160, nothing came out. I had to totally remove it. While out I cleaned it, flushed the system well with plain distilled water, the reinstalled and now all works fine.

 

[6869704x4]

Redneck cooling system flush and clean. Powder Spic and Span if you can find it, if not Tide works OK.
Drain system, fill with water and a couple cups of Tide or powder spic and span. Run for 40 minutes to an hour at medium to high RPM. Drain and flush with water until it comes out clean. I've done this on many vehicles and it has worked. YMMV
You can do this with the thermostat in or out.

 

[North Idaho Wolfman]

Redneck cooling system flush and clean. Powder Spic and Span if you can find it, if not Tide works OK.
Drain system, fill with water and a couple cups of Tide or powder spic and span. Run for 40 minutes to an hour at medium to high RPM. Drain and flush with water until it comes out clean. I've done this on many vehicles and it has worked. YMMV
You can do this with the thermostat in or out.

That's the first time I've ever heard of such a thing???
OH that's right, I don't do redneck fixes.

 

[The Evil Twin]

White vinegar is about the only thing I have ever used to clean a cooling system.

 

[lmichael]

I have also heard of using dishwasher detergent. No thanks. I love on my engines too much to take those kind of chances.

 

[The Evil Twin]

I have also heard of using dishwasher detergent. No thanks. I love on my engines too much to take those kind of chances.

Don't know of that would work or not. But, at least there would not be any unsightly spots on your glassware

 

[fried1765]

That's the first time I've ever heard of such a thing???
OH that's right, I don't do redneck fixes.

Not suggesting that I might do it, but Spic &Span is phosphate free, as well as low sudsing.
Would seem to be a much better option than Tide.

 

[TopK]

Sounds like I should re-do my coolant change and perform a flush - the only thing is I dread trying to remove the lower Rad hose again to drain the Radiator (yeah, I did that instead of trying to reach the drain plug cause the video I watched said "that's the easiest way". It did appear to me that it would be difficult to reach the Petcock. Thanks everyone for your advice!

 

[GeoHorn]

My ‘97-ish M4700DT has never had it’s coolant changed as far as I know. I bought it 5 yrs ago w/400 hrs on it. I am planning a change before this winter… but I’m thinking I should also change the 25 yr old hoses while I’m at it… the thing that I wonder about is…how old are the hoses that have been sitting on the shelf at the warehouse …. what is the shelf-life of rubber hoses anyway..? (In the aviation world it’s about 10-yrs …5 yrs if in-service… I doubt automotive/tractor stuff is any better.)

Should I also consider changing out the water pump as well…despite only 650 hrs on the 25 yr old machine….? (rhetorical question only… while I like to perform “preventive mx”… I don’t like to fix things that aren’t broke.… it’s too easy to cause addt’l failures digging where no hole is needed… I’ve heard Kubota water pumps rarely fail..?)