GF1800 - Front deck Mower PTO Problem

Chessie

New member

Equipment
GF1800-2 and Grasshopper
Jun 10, 2014
5
1
0
Elkton, MD, USA
Greetings from a newbie. I have a 1999 GF1800-2 with 1300 hours on it. It is a good machine, 4WD, front (lifting) deck mower. The (three cylinder diesel) engine runs great.

The (wet-clutch) PTO Stopped engaging all at once... my son said it "clicked" and never engaged.

Here is what I have tried to learn to help diagnose the problem:

There are two safety switches (Seat and PTO Engaged) which both function. If the engine is running, and I'm not on the seat, and I engage the PTO lever, the motor shuts off. If the PTO lever is engaged, the motor will not turnover to start..

I have check all three fuses, and they are good.

I added hydraulic oil to the reservoir and the deck lifts very strong... the hydraulic pump appears to work both the lift and mower (PTO). (there is a separate pump for the hydrostatic drive of the wheels.)

Now here's some extra explaining in case it's useful.

Out of the front of the engine there is a drive shaft connected directly to the engine, so when the engine spins (runs) so does this drive shaft. It goes into and through the wheel drive pump, and into the next pump, which is the PTO Pump. To engage the PTO, a lever is thrown which physically opens a little hole, allowing oil to flow. (No electric solenoids or valves.) The lift is operated with another lever on the same pump... so I'm figuring that I have good hydraulic pressure. The drive shaft to the clutch has a splined end and that I guess connects to the drive shaft from the engine.

The input of the hydraulic line (when the PTO lever is thrown) goes into the middle of a gear with holes throughout.. and these holes go into the series of wet-clutches...

Everything looks clean and like new.. yet she no workey!

Any suggestions or ideas? I don't mind replacing the clutch pack, but it would be nice to know if that was the problem ahead of time!

tnx...
 
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kuboman

Member
Dec 6, 2009
725
6
16
Canada
If you are getting proper oil flow and pressure to the pto clutches then you have a blown seal in the clutch pack. It is the same pump that lifts the deck that engages the pto. You can check the pressure but if it lifts the deck there should be plenty of pressure/flow to engage the pto. Just for curiosity can you lift the deck with the pto engaged?
 

Chessie

New member

Equipment
GF1800-2 and Grasshopper
Jun 10, 2014
5
1
0
Elkton, MD, USA
In normal use, when you are mowing, if you quickly raise the deck, the mower blades stop running until you stop lifting, then they re-engage... this is what I would call "normal operating procedure".

The hole that allows oil to flow into the clutches is very small, so I'm guessing that if the PTO were in the "on position" allowing oil to flow into the clutches, then there would still be some flow available to lift the deck.

(Now that it is all apart and in my hands, I can't test any more operations until I put it back together.)

So apparently, you're saying that there is a seal within the clutch pack.... I notice a large spring also. So if I'm putting it back together, should I replace the seal and the spring or just the seal? The clutches, from what I can see, look fine...

thanks!
 

Chessie

New member

Equipment
GF1800-2 and Grasshopper
Jun 10, 2014
5
1
0
Elkton, MD, USA

Chessie

New member

Equipment
GF1800-2 and Grasshopper
Jun 10, 2014
5
1
0
Elkton, MD, USA
It looks like the link that I sent doesn't go to a specific model... which may be helpful for people looking for parts, but doesn't help my discussion...

Let me try to attach a PDF that I created showing my PTO:

Thanks again,

Chessie
 

Attachments

North Idaho Wolfman

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L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
Jun 9, 2013
29,549
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Sandpoint, ID
The seal that would be bad would be #80 D-ring, that's the seal for the piston that engages the clutch.
You would also do #50 and the 2 #30's.
Also check very closely for cracks in either #60 or #90.
 

kuboman

Member
Dec 6, 2009
725
6
16
Canada
WOO-HOOO, thanks for the info, I'll replace and inspect what you recommend!

Chessie
Please let us know how it goes and what you find. I have one of these mowers so I will follow with interest.
I wish they would make it so the pto did not stop when you raise the deck. Seems like just a little more hydraulics would cure that.
 

vic gerbasi

Member

Equipment
M110 L3300
Feb 19, 2016
232
5
18
dugald mb canada
I have one of this model as well my blades go around whether the deck is raised on lowered continuously running the only time that they stop is when i get off the seat or i disengage the lever

It starts every single time but i do have a situation - in order to start the engine the brake pedal must be depressed- it used to return automatically but now does not i can reach down and pull it up with no problem and it just running and running just like the ever ready bunny Great machine one of best purchases
 

Gerrygmann55

New member
Jul 30, 2016
3
0
1
Michigan
Thanks to your information, I went here:

http://kpad2.kubota.co.jp/kpad2/PartsInfo.do?bookCd=100K0173&funcCd=&figNo=&himban=&dispType=0

and found a parts breakdown for my PTO "stuff".....

The only thing listed as a "seal", is number 050 on the diagram (P/N 37410-75320). I see that this part is in the whole "clutch pack" area, so I'm guess that's it...

Am I getting warm? Is there any thing else to do while I'm there?

Thank you much!
How much oil does the clutch housing require?
 

Daniel Taylor

New member

Equipment
Kubota gf1800
May 5, 2022
1
0
1
21787
Greetings from a newbie. I have a 1999 GF1800-2 with 1300 hours on it. It is a good machine, 4WD, front (lifting) deck mower. The (three cylinder diesel) engine runs great.

The (wet-clutch) PTO Stopped engaging all at once... my son said it "clicked" and never engaged.

Here is what I have tried to learn to help diagnose the problem:

There are two safety switches (Seat and PTO Engaged) which both function. If the engine is running, and I'm not on the seat, and I engage the PTO lever, the motor shuts off. If the PTO lever is engaged, the motor will not turnover to start..

I have check all three fuses, and they are good.

I added hydraulic oil to the reservoir and the deck lifts very strong... the hydraulic pump appears to work both the lift and mower (PTO). (there is a separate pump for the hydrostatic drive of the wheels.)

Now here's some extra explaining in case it's useful.

Out of the front of the engine there is a drive shaft connected directly to the engine, so when the engine spins (runs) so does this drive shaft. It goes into and through the wheel drive pump, and into the next pump, which is the PTO Pump. To engage the PTO, a lever is thrown which physically opens a little hole, allowing oil to flow. (No electric solenoids or valves.) The lift is operated with another lever on the same pump... so I'm figuring that I have good hydraulic pressure. The drive shaft to the clutch has a splined end and that I guess connects to the drive shaft from the engine.

The input of the hydraulic line (when the PTO lever is thrown) goes into the middle of a gear with holes throughout.. and these holes go into the series of wet-clutches...

Everything looks clean and like new.. yet she no workey!

Any suggestions or ideas? I don't mind replacing the clutch pack, but it would be nice to know if that was the problem ahead of time!

tnx...
Hey, did you ever happen to figure out what the problem was? I'm experiencing the same problem with my gf1800 as well