takeuchi TL8 overheat incident

[damnescavator]

So I made the error of not checking the coolant level on my 2016 Takeuchi TL8 for about 18 months, I thought the overflow bottle was how you check it and apparently the bottle can be topped off but the actual coolant level in the radiator is super low.

So this week I am operating this machine and it shows the high temp bar graph with red top bars lit up, flashes the exclamation mark and beeps. I get out and there's plenty hot air flow coming out the back end so I start to wonder if the fan belt is slipping a little or the radiator fins are clogged. No go on either of those, get back in, everything ok for maybe ten minutes then the overheating starts again. It seems the situation is real, not just faulty indications.

Flip to the temp readout on the computer and it varies form 190F to 250F. I am starting to wonder maybe the water pump is going out or the temp sensor is loopy. This machine has the Kubota 75hp engine.

Cal the local dealer and he says water pumps and temp sensors rarely fail on these engines. He says clean the under cab area which I do. He says if the water level is ok then he's stumped, bring it in for a computer check.

Next day when the machine is cold I open the radiator and low and behold its super low. Dump in 6 quarts of coolant. Machine runs like new, no overheat, problem cured.

Ok to the point. We have an engine that saw high engine temps for a quite a few minutes that day. What do you think the damage is likely to be? Engine failure in a few hours? or nothing? The machine did not exhibit any immediate symptoms of gasket failure for the hours after the coolant was replaced. It ran cool and ran fine.

 

[MG84]

Sounds like you may already have issues if 6qts of coolant disappeared over 18mo. Any signs of coolant leaking or is it burning it? First thing I would do is find out where the coolant is going and work from there.

 

[damnescavator]

Yes I thought of that. I do not see milky oil, weird exhaust smells, rough running or anything. Maybe there's a leaky radiator hose.

 

[Arny L]

Get yourself a pressure test gauge, if you don't already have one. Pressurize system, and look for slow leaks. Another check, would be to warm up to operating temp, shut off, and look for bubbles in rad or overflow. This can indicate head gasket.

 

[damnescavator]

the worst is at now clearly at hand. Today I see this dark black oil bubbling up in the radiator overflow can. Hoping its just a head gasket but god knows how bad it is, gonna tear into it this week. Nice to know rebuilt V3307's are only $8k! Maybe I'll get lucky and its just the head gasket. I guess the buck stops with me as I trusted that stupid overflow tank as a sign the engine had fluids but it was obviously misleading. I've put 400 hours on this machine since I bought it, ok, but I am wondering now maybe coolant leak out was why it went to auction in the first place. It's an old united rentals unit

 

[Arny L]

Before you do anything, check the oil cooler, that is another area where oil and antifreeze can co-mingle. And it would be a lot cheaper than head gasket.

 

[damnescavator]

excellent idea ^, I'll do it. I was visualizing something like the head gasket blew where an oil passage is near a water passage but I'll definitely take that oil cooler to a radiator shop and have it checked out first thing tomorrow. It would be christmas early if that's all it is wrong. I guess I also need to see what shows up in the oil pan also, not sure what's in there yet. All I know today is she's dribbling engine oil out of her coolant bottle and of course that is scary.

 

[MG84]

Let it sit without running for a couple days or so and slowly pull the oil drain plug while watching what comes out. If water (coolant) is in there it will have settled to the bottom and will be the first thing to come out. I'd second the idea of checking out the oil cooler well before condemning the head gasket, head, block or whatever. I'd also agree with getting a cooling system pressure test kit, they can be had fairly affordably from Harbor Freight or the auto parts store and are easy to use.

 

[damnescavator]

Did the engine oil dump, nothing suspicious. Good black oil in sufficient quantity. At this point we have 1. what looks like black engine oil getting into the coolant and 2. a tendency to lose coolant going back a year or more. Haven't pulled the radiator out yet. Thinking to haul it to a shop, not sure. I'm working outdoors and engine work can be sensitive. Definitely suspect a blown head gasket but maybe it's the radiator.

 

[Arny L]

Don’t get ahead of yourself, check with a pressure gauge, you could have a leak that is slow, and gets burnt off, before you can find it. You mentioned 18 months, but how many hours? Is Eng low on oil, dipstick milky. Maybe you got some oil in rad from old container?

 

[damnescavator]

Oil looked fine and was up to the mark. No sign of milky froth or water content. Definitely pulling the radiator out and testing it next. You would have to be right there is a slow leak somewhere. It took 400 hours to burn off 6 qts. The overheat incident last week is why I suspect there is a blown head gasket and of course black oil residue in the overflow bottle is not good. It never did that before.

I decided I am doing my own work on it, the dealer's labor rates are like $125/hr and I was quoted $25,000 to put a new engine in it while you can buy a new Kubota V3307 for $12k online. There's a shop that does tractor work around here too, but I used them several years ago and they effed my job up. Same job effed up, twice.