DK45 HST blues

[K5lwq]

I think you got it this time!

 

[Billrog]

Stay cool Harry , you'll soon have a good feeling of accomplishment.

 

[Harry in Ky]

Stay cool Harry , you'll soon have a good feeling of accomplishment.

Would you care to bet on that?

Today's installment is more bad news. I got it running this afternoon for maybe thirty seconds, probably less. The leak is still there, same place. But wait, there's more. The piston stuck again!! (yes, in that a short a time span) When I bolted the pedals back on it seemed both were travelling full stroke. I had tested the lever arm going into the control valve after installing the unit back into the clutch housing. It was going back and forth from forward to reverse, and returning to neutral just fine. After starting the tractor I tried both pedals again and they seemed to work properly. When I got on it and tried to put it into gear it wouldn't go. Felt like it was just grinding. After playing with it gently for a few seconds, it slipped into M range and promptly started travelling forward. At this point I have no brakes or steering hooked up yet, so it's only a jury rigged switch to power the fuel stop solenoid and a remote start button. I shut it off and went for the pedal linkage again. This time it will go towards reverse a slightly longer distance than before I started on it, but not much.

I talked to the owner later, and he told me he has located a kit of some sort through Bobcat for the unit. $2500, but it includes a new piston assembly as he understands it. I don't know any more about it than that. I need to make some decisions here.

 

[K5lwq]

Well crap! I can not believe that piston stuck again. I would sure like to understand the cause of this problem but if I was in you shoes I believe I would tell the owner it is time to go a different route.

I think instead of a kit for the unit he should be looking for a complete replacement unit. Either that or we would have a good understanding of how we move forward so your time is compensated properly even if it never works again.

I sure hate you have to deal with that BS and hope the owner is taking care of you!

 

[Harry in Ky]

Turns out the "kit" he mentioned is only a rotating group. ONE rotating group. Not really part of the problem at all. The latest option was a complete unit at $6500. A tough bite to swallow, but at this point options are few. I'll wait and see what he decides.

In the mean time I'm looking around for somewhere that works on them. I found one place online somewhere in Ohio called Wooster Hyrostatics. Their website shows promise, but reading between the lines I get the feeling their prices will be right in line with a new unit.

 

[K5lwq]

Turns out the "kit" he mentioned is only a rotating group. ONE rotating group. Not really part of the problem at all. The latest option was a complete unit at $6500. A tough bite to swallow, but at this point options are few. I'll wait and see what he decides.

In the mean time I'm looking around for somewhere that works on them. I found one place online somewhere in Ohio called Wooster Hyrostatics. Their website shows promise, but reading between the lines I get the feeling their prices will be right in line with a new unit.

Well he can not buy a replacement 45 HP tractor for that price and as it sits it has little value. Still think his best bet would be pay the $6500 for The new one and pay you for your time. Afterwards he will have a good little tractor again and can work the cost back out of it.

Makes me glad I always like gear drive over HST. HST can get expensive in a hurry no doubt but I guess to some people the benefits out way the cost.

 

[Harry in Ky]

There are definitely pro's and con's to both. I once put three clutches in as many months into a little l3250 Kubota. They traded for something with a hydrostat and have been happy with it ever since. Hydrostats are great for people who really don't know how to treat a tractor but insist on running one anyway. On the other hand, for those who need a tractor for working, and not for homeowner chores, gears are the only way to go. More usable power and less wasted energy.

 

[Harry in Ky]

Okay, we're back. The owner has made the decision to spring for the $6K+ new replacement transmission. The local Bobcat dealer came through, produced the unit, and took his money. That was sometime last week I believe, and he has been on my case ever since. Gently, but consistently.

So today I got back to it, split the tractor, swapped out the units and rolled it back together. Hopefully tomorrow I can get enough "stuff" hooked back up to get it started and tested before final assembly. We'll see.

One interesting point he made while I was there. He mentioned he had been in contact with number of Kioti dealerships in various other locations in regard to repairing, rebuilding, replacing, etc, this unit. Not much luck on any of that. However, he said that at one of the dealers he spoke with someone who was aware of the "sticking piston" problem. The details of the conversation are sketchy, but this fellow claims that this is not a new, one time situation, but that other tractors have done this as well. His claim was possibly a design flaw, and that it was not repairable. A new transmission is the solution. I've had no contact with this person so I can't elaborate on what he said or what he based his conclusions on, but I do find that interesting. Depending on how this project shakes out I may try to contact him and see if I can get a little more information.

More updates coming.

 

[K5lwq]

Glad the owner made the right decision and it is on the way to recovery and out of your life! You would think if this was a wide spread issue we would have heard of this before. It also is strange that it is not repairable. Hopefully the owner can have many trouble free years on the new unit. Thanks for the update.

 

[Harry in Ky]

I don't know about how widespread an issue this is, but unless this guy is just blowing smoke, ours may not be the only one. Either way, whether it's repairable or not, I can think of more fun things to do than to try it again.

 

[Harry in Ky]

More good news today. I had it running for a little while with good results. It shifts without issue, has forward, neutral, and reverse. No leaks (not yet anyway) that I noticed. I didn't run it long and couldn't do much without steering, but the transmission seems to be okay so far, The floor plate is back on, the steering column, brake pedals, and all that assembly is back in place. The lines to the steering valve took up most of the afternoon. I'm certainly no fan of BSPP fittings. I think it's the fine thread that makes them so difficult to start. They have to be lined up nearly perfect for a thread to catch. Not very forgiving. There's still a lot of electrical to hook back up, dash, switches and all that.

Going to let it sit until next week sometime. I feel pretty good about my chances of getting away from it now. I do think the bulk of the frustration is behind me.

 

[Harry in Ky]

So much for what I think. Things are pretty much all assembled now, except for the plastic panels around the steering column. I have (at least) one more issue to resolve under there. The dreaded "no start" condition. As in "no signal to the starter solenoid". This was there the first time I had it back together, but I didn't really get too excited about it, figuring I could sort that out sooner or later. I just used a remote start button for my purposes and moved on.

Now I need to sort it out. Two stumbling blocks I can't seem to get past. 1) Part of the start signal goes through the operator aggravation module. Somewhere in there is a second start relay that evidently only activates when the module is satisfied with all that it oversees. I see no easy way to test that. 2) There is a range shift safety switch involved as well. This is the biggest obstacle at the moment. I've spent most of this afternoon studying the Bobcat electrical section and its included diagrams, in addition to the PDF on the DK45. In neither of them is there a clear picture of how that switch fits into all this. It doesn't show up on any diagrams in either manual. I see references to it in the Bobcat manual, but not in any context to show where or how it connects.

The actual start relay is on the firewall in the engine bay. It has power to the main terminal. The load circuit does lead to the starter. The coil circuit has ground on one side. There is no power coming to other side in start position. There a few "creative"options here, but I'd like to keep as much as possible of the safety features in place. The range shift switch for sure, if I could just figure out what wires to look for and where to look for them. In the end I may end up running new wires back there and working them in as needed.

 

[Harry in Ky]

A little more studying last night and I made a couple more discoveries. The range shift sensor (that's what they call it) isn't directly tied into the start circuit at all. I finally found it on the diagram off in a corner near the cruise control/preheat unit. It operates mainly through that unit, and its function is to select (and illuminate) an indicator light on the dash. Four lights, actually. L, M, H, and N. When the N light is on a signal is supplied the aggravation module. That in turn decides what the start and fuel stop relays do. Gotta love these simple little tractors. This darn diagram is all condensed down onto one page, a reprint at that, and rather feint in color. I have a lighted high power magnifying glass and really have to work to read any part of it.

So armed with that I plan to take another shot at it today. If the diagram and color coding match the tractor, I expect it to start with the key today, one way or a another.

 

[Harry in Ky]

Well I feel better today. I think I'm finally separated from the ball and chain. I went through the motions again, the neutral light is on, both brake pedal switches are working, PTO is off. Still the module refuses to let the starter operate. I'm done chasing circuits. The creative option was the order of the day. The start signal wires in and out of the module are now externally connected, and it starts with the key.

Miller time.