[mike82]

I hope it's fine I post this here.

Last Friday I purchased a T-B GTX20. It appeared to be decent deal. The tractor came with a rototiller, snow blower, snow plow, winter cab attachment all for $2300. It's a earlier model with the Kohler M20QS. the guy admitted he knows nothing about these tractors. It came with his house and he wanted a zero turn as it's faster cutting the grass. He said he replaced the head gaskets and the float on the engine. The engine starts right up and is very smooth from low midrange throttle to high. However, the engine slightly backfires on low idle and jerks a little. The hydrostatic drive runs smooth the only issue with hydraulics so far and he told me about was if you put the mower deck drops back down overnight, which I found to be the case. Would that be a hydraulic cylinder issue or a hydraulic valve issue? Also he mentioned the main fuse blows when you try turning the headlights on and the cruise control he could not get to work. He thinks is all related. When I got it home, I tried the cruise. In the on cruise position the light comes on but wont hold the peddle. If I hit the cruise reset the light gets super bright as if it's getting extra voltage to the light. Then sure enough, when I turned on the headlights none of them came on, but shortly after the engine started sputtering and just died. I've attached picture of the fuse that blows and a wire I found that looks like a repair going to the PTO possibly? Now, I can turn on the PTO and it runs just fine. Any ideas on where or how to start trouble shooting the electrical issue? Last, I dunno if this is an issue or not. This is my first Kohler opposed twin. For whatever reason after changing the engine oil (SAE 30) and Kohler oil filter. I noticed a decent amount of air blowing out the dipstick hole. I thought right away I have blowby due to bad rings? However, some posts I looked up said this is normal with opposed twin kohler engines and others have said it's not normal. Anyone with the M20QS notice if they have air coming out of the crankcase to be noticeable? When I installed the new spark plugs the old ones appear to have a clean burn and there was no oil on the filter or in that area. So that's a little confusing. I have a cylinder compression gauge coming in today. I see what it reads. I also changed out the trans fluid as the old was a non-transparent black with TS universal tractor hydraulic / trans fluid and a new Napa 1416 filter. The steering seems a little harder than the GTX-16 I have, not by much. Dunno if that's normal.. The unit has about 680 hours on it...

Any advice is greatly appreciated...

 

[DL-North]

I also have GTX 20, but it's the later model with the Vee twin, but, I also have an elec problem, as that same fuse in mine is blowing, usually when I engage the PTO/deck. I suspect a short in one of the safety circuits as the wire gets hot even with the PTO off.

I highly recommend searching the web for the manuals for your year tractor.

Good luck,

 

[mike82]

I also have GTX 20, but it's the later model with the Vee twin, but, I also have an elec problem, as that same fuse in mine is blowing, usually when I engage the PTO/deck. I suspect a short in one of the safety circuits as the wire gets hot even with the PTO off.

I highly recommend searching the web for the manuals for your year tractor.

Good luck,

I'll do that, thanks!

 

[mike82]

Hi Dan,
Just wanted to let you know I found a couple manuals online! Perfect advice. I was shocked you can easily download all those manuals. It turned out to be a undersized fuse. The electrical drawing called for a 30amp fuse. A 20amp was being used...

 

[dave_r]

thanks for coming back and posting what the fix was.

 

[nsconductor]

It is not an abnormal condition to have the hydraulics bleed down overnight. Mine actually bleeds down over 1/2 hour a little bit. Yes you can rebuild the control valve and hydraulic lift cylinder but is it really worth it just to keep it from bleeding down overnight? When i park the tractor I always put all attachments down anyway. Keeps any stress off of linkage etc.

There is a slight amount of crankcase pressure in the crankcase if you pull the dipstick while its running. If your not seeing oil in the air cleaner or all over the top of the engine and the plugs are not oil covered I would think all is normal. There is supposed to be a positive crank case pressure (just like in a car, pcv valve or positive crankcase ventilation valve) I wouldn't over-think some of these little issues and make a mountain out of a mole hill. Remember this tractor is 30 plus yrs old.

That M20QS weighs a little more than the 16hp in you gtx 16 so steering effort could be more or some of the steering linkage may be slightly worn compared to the gtx16 thus more drag Different design tires and tire pressures can cause different effort I just changed to old original Goodyears for a new set of Kenda K500 Superturfs with a higher load rating and the effort is drastically less with the newer tires as they hold 21lbs of air vs 10-12 in the old Goodyears. Loads of different variables to deal with.

 

[DL-North]

Mike,

Thanks for posting the solution, now I need to check, mine, the wiring diagram does show a 30 amp for mine also.

In my case, the wire is very hot to the touch, so I likely have more going on.

I'm getting close, I spent the afternoon cleaning the oil off and starting to put the engine brackets/mounts back on. Someone (either the PO or me) "bumped" something and bent the brackets and moved the engine rearward about 1/8-3/16 of an inch, meaning the PTO drive belts aren't in alignment. And the new PTO belts (OEM) I got seem to be longer then what came off, so I need to deal with that also. Maybe tomorrow it will be running and I can search for the elec issue.

Hi Dan,
It turned out to be a undersized fuse. The electrical drawing called for a 30amp fuse. A 20amp was being used...

 

[mike82]

Mike,

Thanks for posting the solution, now I need to check, mine, the wiring diagram does show a 30 amp for mine also.

In my case, the wire is very hot to the touch, so I likely have more going on.

I'm getting close, I spent the afternoon cleaning the oil off and starting to put the engine brackets/mounts back on. Someone (either the PO or me) "bumped" something and bent the brackets and moved the engine rearward about 1/8-3/16 of an inch, meaning the PTO drive belts aren't in alignment. And the new PTO belts (OEM) I got seem to be longer then what came off, so I need to deal with that also. Maybe tomorrow it will be running and I can search for the elec issue.

It's a possibility of a bad wire you have as well.. I've seen that plenty of times with new manufacturing like where I work. As the systems come together (electromechanical) Sometimes the systems on new turnup will keep blowing fuses.. The electricians will be all confused to only learn after wire checks.. in a lot of cases it was a pinched wire someplace not seen.

Also, something I noticed after reading more and more.... It appears the GTX20 models suffer more hydraulic issues and damage than the GTX16 owners... With having both models on hand the casings look the same... yet the odd thing is the dipstick sizes.. the dipstick for the GTX16 is shorter than the GTX20 models... if anything I would think this should be reversed? More hydraulic oil for a larger system? COuld this have been something missed at the factory?

 

[DL-North]

Ya, that's what I need to check for, thou it did build up gradually.

As for the sticks, IIRC, the 16 hp version has the single sp rear, and the 18 and 20 have the 2 speed, maybe that's why the difference?

 

[mike82]

Ya, that's what I need to check for, thou it did build up gradually.

As for the sticks, IIRC, the 16 hp version has the single sp rear, and the 18 and 20 have the 2 speed, maybe that's why the difference?

You said it happens when you use the pto? I wonder if the electric pro is shorting out? You can check continuity and resistance on those. What happens if you unplug the cable going to the electric pto and flip it on. Does it still blow the fuse?

Yes, the 16 has no high or low setting. The system on the GTX20 is a little larger. So I'd assume a shorter dipstick for more fluid volume. However, in this case the dipstick being longer.. your essentially keeping less fluid in the reservoir on the 20 versus the 16.. I find that odd. I wish someone had more input as to why. However, does not seem like many gtx owners on this forum. I may post that else where to see if I can get some answers. Where the "M" is stamped on the dipstick is where the operating level is marked on the 16. To give you an idea of the difference...

 

[mike82]

It is not an abnormal condition to have the hydraulics bleed down overnight. Mine actually bleeds down over 1/2 hour a little bit. Yes you can rebuild the control valve and hydraulic lift cylinder but is it really worth it just to keep it from bleeding down overnight? When i park the tractor I always put all attachments down anyway. Keeps any stress off of linkage etc.

There is a slight amount of crankcase pressure in the crankcase if you pull the dipstick while its running. If your not seeing oil in the air cleaner or all over the top of the engine and the plugs are not oil covered I would think all is normal. There is supposed to be a positive crank case pressure (just like in a car, pcv valve or positive crankcase ventilation valve) I wouldn't over-think some of these little issues and make a mountain out of a mole hill. Remember this tractor is 30 plus yrs old.

That M20QS weighs a little more than the 16hp in you gtx 16 so steering effort could be more or some of the steering linkage may be slightly worn compared to the gtx16 thus more drag Different design tires and tire pressures can cause different effort I just changed to old original Goodyears for a new set of Kenda K500 Superturfs with a higher load rating and the effort is drastically less with the newer tires as they hold 21lbs of air vs 10-12 in the old Goodyears. Loads of different variables to deal with.

I apologize I never noticed your post! Thank you for all that extra detail! I agree about not over thinking it. I was just concerned if this was normal or not. There was no oil on the plug and I actually purchased a compression tester. Each cylinder was around 105 psi.

As for the Hydraulic cylinder drifting. My concern is if I got to put the rototiller attachment on or the snow blower. It will quickly drift downward. So I'll be sitting there working the handle constantly to keep it in the up position or it might not be able to keep pressure down as well. Am I correct in being concerned of that?

 

[DL-North]

Ya, I wonder that also, and yes, with the clutch on, the fuse blows fairly quickly, but,
even with the clutch off, the wire gets hot and eventually the fuse blows.
I've been waiting (putting off) really searching for the problem until I get the front end back together.

The tractor has been down all summer, started with replacing the deck spindle bearings, and while removing the deck, discovered the ft eng mounting bracket/s bent and the PTO idlers shot/seazed and bad belts.

And all the wear points had what I think is excessive wear for 500 hours. So lots of finding pieces to "fix" bad joints and straightening bent metal. And I was probably being too cheep in this repair, as I previously bought a spare deck for the parts, so I'm using what I can from the 2 decks, and buying new what I have to.

After seeing all the wear, I'm wondering if the PO might have payed some games with this one and I over paid, who knows, that was 6 years ago.

You said it happens when you use the pto? I wonder if the electric pro is shorting out? You can check continuity and resistance on those. What happens if you unplug the cable going to the electric pto and flip it on. Does it still blow the fuse?