Make Sense to Retrofit a Coolant Recovery Tank?

[Teese]

My 1995 era new-to-me B20 was factory equipped with Kubota's then version of an idiot light ... the "overheat warning" whistle on the coolant overflow tube. Does it make any sense to now retrofit an aftermarket coolant recovery tank (on the theory that the universal appearance of these in subsequent years certainly represents some nature of mechanical wisdom)? If so, any urgency for prioritization on my project list?
Part of me thinks that retention of the whistle preserves its own sense of urgency should I encounter an overheating situation -- or do I counter that with adding a tank only if I also install a temp gauge?
Another part of me thinks that I may not ever even hear the whistle as long as my hearing "protection" consists of noise-canceling headphones thumping out tunes from my phone.

 

[North Idaho Wolfman]

Over flow and temp gauge are good bets, but the temp gauge can be a little tricky to put in those older tractors.

 

[Orange Tractors]

It depends. I'm not familiar with your tractor. Does it have a for real water pump and thermostat, or is it the older Thermo-Syphon system like my L175 has?

In my opinion, if it has a circulating pump and thermostat, I would put the gauge and recovery system on and keep a good eye on the gauge until you know where normal operating temperature is.

If it is the Thermo-Syphon system, where the water has to boil to circulate. I would simply clean the cooling system (and whistle) and leave it alone. I really do not enjoy watching a water temperature gauge that is normally going to read 240F degrees or so .

Like I said, just my opinion.

Robert

 

[lsmurphy]

Mine runs cool, cooler than I think it should.

Yeah, I've added coolant twice in the last year, It loses about 2" of coolant about every 30 hours or so......not worth the effort of a recovery tank to me.

 

[Teese]

My B20 has the D950-A-T engine and indeed has both a water pump and thermostat. I'm sensing a bit of "You can if you want" as opposed to "Yesterday wasn't soon enough".

 

[Bluegill]

I wouldn't retrofit. Never had any trouble with my old Kubotas.

But I would turn down or turn off the tunes so I could hear what the tractor is doing.

 

[phaser]

I've added coolant twice in the last year, It loses about 2" of coolant about every 30 hours or so......

My B7100 essentially does the same thing.

So, is this normal on these thermo siphon engines it have to add coolant regularly?

It's been driving me up a wall, as I can't find any obvious leaks, and it's not going out the exhaust either.

 

[Orange Tractors]

My B7100 essentially does the same thing.

So, is this normal on these thermo siphon engines it have to add coolant regularly?

It's been driving me up a wall, as I can't find any obvious leaks, and it's not going out the exhaust either.

phaser, I don't know what is "normal" as this L175 is the first thermo syphon cooling system I have ever been around. I will say that I have to add coolant to mine over the course of the summer.

My L175 has a Woods belly mower on it so it is used mostly as a lawn mower, and occasionally moves trailers. I use my old WD for any real tractor work I have to do.

If I let the grass get tall enough that I can't mow in 4th, the tractor will overheat in hot weather. Most times I mow the yard and the temp is over 85*F, I can see a wet spot on the front axle from the steam condensing out of the whistle, although the flow isn't enough to sound. I check the level of fuel oil and water each time I use the little Kubota, just to make sure.

I clean my cooling system every year or two, or at least try to. I use washing soda to clean, then flush it with clean water a couple of times before refilling with new antifreeze and water.

I check the freeze protection every fall since I really don't want things to freeze up and break.

From what I have learned while reading some antique tractor forums, some American tractors were produced using the thermo syphon system; but the newest ones I can think of were last sold in the early 1950's. The system is supposed to work okay, you just need to keep everything clean and the level topped off. It just seems really strange to anyone that has never been around an engine without a waterpump.

While I am not totally sold on the thermo syphon system, I do like the fact that I used less than five gallons of diesel to mow my yard this year. When I was using riding lawn mowers, it was roughly one gallon of gasoline every time.

hope this helps,

Robert

 

[phaser]

I will say that I have to add coolant to mine over the course of the summer.

Thanks, your post is helpful.

My operators makes this statement: "When the cooling water mixed with anti-freeze decreases due to evaporation, replenish with water only."

So that indicates that normal evaporation does takes place. My operators manual does not makes mention of recommended antifreeze to water ratio, but 50/50 is the general consensus here.

On the net, I came across an article on Yanmar thermo siphon engines. They recommended only a 25% antifreeze mix for proper cooling due to how viscous the mix is. But that only gives protection down to -4f. These engine apparently have an overflow bottle which allows coolant recovery when the engine cools.

So, to summarize, it appears to be normal for Kubota thermo siphon engines to "use" coolant through evaporation.

I like the idea of possibly adding an overflow bottle.