Issues with new to me B7100 HST

Good evening all,

I picked up a 92 B7100 HST about 6 weeks ago. I have been acquiring implements and using the ol' girl for mowing, moving heavier items, pulling a 6' x 12' utility trailer, etc. Tonight, she fired up as normal, and I began mowing. Within 5-7 minutes of mowing, she started losing power, so I disengaged the PTO and made my way to the back barn. I made it to the apron before it stalled on me.

She will crank and fire, and within 3-5 seconds stall out again. Did that twice before I pulled the key and came inside. And of course, tonight we get a thunderstorm...

Since I have had it, even when looking at it before purchase, she would blow some whitish smoke for a few seconds upon startup. Shut it off for 5 minutes, start it up, and she smokes. But it always clears up. Always.

I did a fluid and filter change when I brought her home, with Kubota filters and fluids. I did top off the radiator before running her after the fluid change. And a gave it a general once over, so I was confident putting her into service.

Tonight I did top of the antifreeze with some 50/50, checked the oil, and began to mow. I noticed the right front hub was wet, and the radiator was low, and there was antifreeze on what I assume is the whistle on the end of the radiator bleed hose.

My thoughts are the radiator is going out, and as such it may have gotten hot and that caused it to stall. I let it set for about 3 hours, so it should have been ambient temp or close to it when I tried to start it to get it into the garage before dark. I blew the radiator on an older Cummins, and it was over 240 before I got the hose to the radiator to cool her down. Let it set overnight, the old Cummins fired up and never missed a beat.

Could I be so lucky with the Kubota, or do you think serious damage was done? I did check the oil, as I do before every use, and there is NO antifreeze in the oil. The level never varies on the dipstick. And the trans fluid is not overfull either.

I would be appreciative of any and all insight you folks have to offer. Right now I am saddened my ol' punkin is setting outside overnight in the rain with no way to get her up the hill and in the garage to dry out.

Good evening D2 , thank you for the response. She had fuel when I bought her, and I have added over 2 gallon as I use her. I also added some Power Kleen to the tank this last top off.

Yes, she will fire and run for a couple of seconds. Would injectors smoke for a short spell and clear up? I do get the occasional puff of diesel that the old ones like to emit when under good load. Until this afternoon, she was running good. I have heard no whistle, although I am unsure what I am listening for. But nothing sustained.

Setting here thinking about it, I am wondering if I should remove the radiator and have it pressure tested? If it tests good, place it back into service. If it does not, would it be better to recore it, or replace it? I would lean towards replacing it, but not sure until I hear from others. I will be replacing both hoses with stock Kubota hoses if I am able to find them.

Should I be worried about the head gasket if there is no antifreeze in the oil? It is a fresh fluid and filter change within the last 7 hours, and it is just a tick under full.

Good morning fellas, the previous owner told me he used the 7100 for snow plowing, but had sold the blade last year. It was just setting in his garage, as he had bought a Kubota ZTR. The previous owner did not appear to be too mechanical. History for the most part is unknown.

I have a 71 Nova I converted to a big block, my old Cummins I swapped injectors, fuel pump, exhaust, etc on, a Harley touring bike, 2 old Case garden tractors. I am no mechanic, but I am capable. I did download the WSM for the tractor,

1147 hours on the working hour meter. There are no signs of hydro locking at this time, thankfully. I worry about the head / gasket as I have read about the overheating these may be prone to, but at the moment that may not be the primary concern.

Based on your input, I am leaning towards some Power Kleen diesel 911, new fuel filter, and bleeding the injectors. Does that seem to be correct? If I buy the diesel compression tester, what numbers am I looking for compression wise? And if compression is up to par, is it better to replace the injectors or have them rebuilt? If replacements are warranted, is there a preferred vendor? I really enjoy this ol' girl, and some love to get her back I can give to her.

Thank you both for your input!

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Well, I was able to get the 7100 back up and running today. Turns out the last mow was the final vibration for the fuel tank repair that the prior owner had done. Epoxy finally let go, and my fuel drained until she was gasping. Pulled the tank, found the issue, filled it about half full, bled the fuel system, got her fired up and back into the garage.

First order of business is a replacement tank, lines, etc. The filter was changed today. The good news is the pump is working, and when she has fuel she runs. So until I am able to find and obtain a tank and new lines, she is on limited duty. After that is radiator hoses and pressure testing the radiator, and replacing if necessary. If it holds pressure, a good flushing and fresh coolant. If the radiator needs fails the pressure test, I will get a quite to recore and balance that against a new radiator.

For the moment, injectors are on the back burner. I have a small riding mower to mow with until the punkin is back in good health. I thank you all for your input, one system at a time until she is back to the workhorse I need.

The previous owner had epoxied the bottom of the tank, and it finally let go. As well, it appears to be weak under the rear strap, and flaking off in layers. I would feel better if I could source a replacement, rather thank try to patch a worn tank. I am rather fond of this old girl, and want her back in working order.

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Thank you for the link, NIW, I have a message out to @007kubotaguy, depending on his response I may go the new route. Your assistance and guidance is most appreciated. One system at a time until she is back in good working order.

PM replied to, thank you Lance.

I would agree, thank you for the link to Colemans as well, it is most appreciated.

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Quick update to the 7100. 007KubotaGuy sent me a good tank, it will arrive this coming week. I tested resistance on the glow plugs, got 1.2-1.3 on all 3, so they appear good. Pulled the injectors and had the local Kubota dealer test them, 2 out the 3 had irregular spray patterns, so 3 new OEM injectors will also arrive this week. I ordered the upper and lower hoses for the radiator.

Once the tank arrives, I will clean it well, install it with new lines, install the injectors, fill up and fire up. Bring it up to temp, pull the lower hose, drain the cooling system, and pull the radiator. Pressure test it, if good give it a good cleaning inside and out, reinstall, and fill with 50-50 mix. All other fluids are less than 12 hours old.

Only other issue at this time, is the front tire slips the bead and goes flat. Have to jack it up and strap it to get it to take air. Thinking about the starting fluid trick to pop the tire on the bead, and see what happens. Worst case it doesn't work, and new tires are in order. Wouldn't mind R4s in that case, but will likely go with the tires many went with, the mild R1s on rear and Kendas up front.

Once again, I appreciate the help as I work this ol' girl back into fighting shape. Hoping for many more years together.