Kubota G18 surgery!

   #1  

Grrrr

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Jul 17, 2007
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800
Location
Devon, UK
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John Deere!
I have just brought a Kubota G18 which is very similar to the G2160-R48S Direct Shoot mower you have in the US (except it has an 18HP engine instead of 21HP.

It is a 1999 model with 1050 hours but it is in superb order, been really well cared for.
In this country these mowers are in very high demand, I had to pay 」3500 for this mower, which is about $5500, but a mint one with 200 hours would be more like $7000 dollars which was too much for me. We're about 40% more expensive on new over here as well.

When I brought it, I intended on stripping it right down, going over everything with a fine tooth comb, respraying anything that needs it, and reassembling it. Today I started that process.

Here are some pictures of the mower (I shall take more soon, I only had my mobile phone camera today):

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Unfortunately there is some work to do. As I started stripping the mower down, I found that the floor pan in the rear collector shoot that pivots up is about the only part that has rusted - and it has well in truly rusted out. Great big hole in it. I assume it was left with wet grass in the shoot for some time. I will order a new flip up floor pan for it, because I would waste more time fabricating and welding one than a new one will cost.

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(The hole looks smaller than it is in this photograph).

The second major thing I found was that something has hitthe bottom of the tractor at some point, and smashed the HST fan (or so I thought).

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But on closer examination, I realised it wasn't just the HST fan that was smashed. There is some sort of hydraulic pipe that comes out the bottom of the hydrostatic pump, around the fan, and up under the seat area somewhere. But this has actually been bent, the round pipe has been compressed like it has been pinched reducing the flow, and was now in the path of the fan causing further destruction. The dealer who sold it has offered to cover the cost of parts, which I thought was fair of him seeing as I brought it as seen rather than letting him service it and add another 」1000 to the price :)

So this pipe will need removing, a replacement ordering and then fitting. And then the HST fan can be repaired as well. I looked the pipe up in the manual before I went to do any ordering, and it is some sort of drain pipe, and according to the Kubota dealer, it isn't going to have actually caused any harm, but he still recommended replacing it, as otherwise it would mean the two gearbox units would start pushing oil out of the breather pipes. The fan is way to fragile for what it costs as well!

I then began stripping the mower down. It comes apart quite nicely, the seat comes off, the dash all lifts off and then the rear fender panel slides forward and comes off. About 15 bolts to undo in total.

However, I couldn't actually dissamble it tonight as the big set of socket wrenches were in the other workshop and the steering wheel bolt is 24mm and my other set only goes up to 22mm :( But it is all ready to go once I can pop that steering wheel off.


I then went round the tractor and worked out all the bits I needed to order:

  • PTO lever trim
  • Hydraulic lever stickers
  • PTO sticker
  • Operators station mat
  • Brake pedal rubbers
  • Deck height adjustment knob and stickers
  • Dash indicator lights sticker
  • Dash sticker kit
  • Rubber flap for collector
  • HST fan
  • Mesh grill for collector
  • HST drain pipe
  • HST pedal springs
  • Throttle springs
  • Rubber trim for rad screen
  • Rubber pads for bonnet on dash
  • Collector safety switch
  • Decal kit

They are all fairly small bits but all things that will annoy me. The mat was a bit torn in places, but more importantly, it had an abundance of grass / crap trapped underneath it which I wanted to remove to stop it from rusting. It also tore fairly badly when I lifted it to remove the bolts under it as it was brittle.

I also ordered a cruise control kit (why not!) and a front PTO kit (future plans :thThumbsU)

I intend on respraying the bonnet and the fender pan totally as the bonnet is a little faded with a few dents and the fender pan has some marks and is a little messy.

The rest of the tractor will just be touched up where necessary depending on how fair I strip it down.

The mower deck is in great condition, I will strip it down though and respray it as well.

Then the mower will be back to as new condition after a full service. Then I can work on making a front mounted rotary broom for it :fing32:

Has anyone got any tips on respraying a plastic bonnet? It was obviously sprayed at the factory, as I can see overspray on the underside.

I will keep this thread updated!
 
   #2  

jinman

Epic Contributor, R.I.P.
Joined
Feb 23, 2001
Messages
21,008
Location
Texas - Wise County - Sunset
Tractor
NHTC45D, NH LB75B, Ford Jubilee
Congratulations Jake! Enjoy your refurb. That's a great looking :thumbsup:little tractor.
 
   #3  

Gator6x4

Veteran Member
Joined
Dec 7, 2003
Messages
2,267
Location
NC
Tractor
Kubota Grand L3830
Enjoy the refurb. If I may share some information I learned one day by listening to a friend that used to own a automobile body repair shop. (Now deceased) He was grumbling about having to redo an area because it was plastic and some primer or paint had contacted the plastic part. I do not remember if he said plastic takes a special primer or it takes a special primer and paint. This may be something to discuss with a local paint supplier prior to painting.
 
  
  • Thread Starter
#4  
OP
Grrrr

Grrrr

Platinum Member
Joined
Jul 17, 2007
Messages
800
Location
Devon, UK
Tractor
John Deere!
Well today I got a little bit further into the teardown. Don't have a lot of spare time at the moment and the weather is miserable, wet and cold.

I'll have to split this update into a few posts as I can only post 4 photos at a time.

I finally managed to get the top off the mower after much pondering on it last night. There is a deck height adjustment knob that sticks out between your knees - and you have to take the stalk it sticks out on off to remove the fender pan.

Well I couldn't work it out for the life of me - it just did not seem possible to remove it until you had the fenders / seat area lifted off - but you couldnt lift the seat off without removing it!

So I gave my local dealer a ring (not the one I brought it from), and the workshop there were able to enlighted me. Turns out you can pull the shoot that runs through the mower out from the rear of the mower. This then allows you to put your hand in and line up a 15mm (typical Kubota, awkward size) spanner on the rear of the shaft. And then by lowering the linkage all the way down on the hydraulics, you can lock the shaft off so it doesn't turn when you undo it. The whole process only took about 5 minutes once I knew what I was looking for - it didn't help that the mower had 10 years of caked on mud around this nut!

Anyway, once I sorted that I was away. Fender pan lifted off. Total time taken nearly 4 hours, (with a lot of tea drinking). If I did it again I could have it off in 15 minutes if I was in a rush I reckon!

Here are the photos of the mower with the dash and fenders removed:

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Here you can see all of the dash taken out. I had to take care to label all the indicator lights along the top of the dash as otherwise I would have had a fun job workign out which cable connected to which light again! In this photo you can also see the fan that was the cause of this project - the famous HST fan. The broken HST drain pipe will also now be easy to replace.

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Here is a photo from the front of the mower. I was really surpised at how heavily built this mower was compared to the mowers I have had in the past. It really is a big tractor condensed down. Everything is made of 1/4" plate or thicker. All captive nuts as well so it is lovely to take apart. In this photo I have already done a lot of cleaning up. The fuel tank sits underneath the seat (removed in photos) but there was a wheelbarrow full of crap and old grass under there and especially above the HST housing. It is very difficult to clean these areas on any mower, but espeically on this one considering how big the HST is and how cramped the mower is inside squeezing so much in under the seat (grass shoot to collector, fuel tank, HST unit, differential, drop down wheelhub gearboxes and hydraulic pump / valve block as well as the mower deck lift linkage / cylinder! And it is all under the seat!

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The steering on this mower is interesting. It is not the typical 'power steering' with hydraulics and nor is it the hydrostatic steering usually found on mowers and tractors. Instead, it is some sort of rack and pinion system, but it has a whacking great electric motor that kicks in as soon as you start turnign the wheel. I have to say I quite like it, and there is no slop in the system at all, and I think it is more precise than hydrostatic steering. But it is not as light as hydrostatic steering - but I think the motor may be a little week on my system, need to check that one out. It took me a long time to get that wheel off as well, had to get the hydraulic pullers out as it was well in truly stuck on the splines.

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This is the back of the mower, with the hydraulic levers shown. You can see some of the areas of rust on the rear collector here, which will be repainted. I haven't decided if I will continue to strip the mower down or if I will repaint these grey areas in situ. It is going to be quite a major operation to take this back bit off. I do still need to clean up around the hydro unit by removing the cover on top of it. My plan is to scrape everyhting I can off and then I will drag it outside and give it a good wash with the steam cleaner to remove the last of the junk. I think this is the first time it has been stripped since it was built in 1999.

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This is another shot of the mower looking forwards. You can see a rubber flap in the bottom left side of the photo - this needs replacing as it is disintergrating and it is what prevents grass from blowing back up at the operator - and it really is necessary. The airflow that the blades generate is incredible.

The big lever stickign up is the PTO lever, this is mainly all OK but I made some adjustements to the cable lengths to correct some slack in it.

You can see here more damaged paint. I think will strip all the items like this off and take them to be sandblasted. It will be much quicker than me trying to clean them up myself and then they are ready for paint.

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Here is the engine compartment. The battery is new (the dealer who sold it to me put it in before it left). There quite a lot of dust junk around the dash which I have sc***** out. There is also a lot of crap down in between the radiator and the battery stand, which has caused a sealing foam to perish. I will have to strip the radiator out and replace this I think. You can also see the air filter intake, this needs replacing as it has all melted and deformed at this end, but that is an easy job and I may see if I can fix it with a hot air gun. I was impressed with the wiring loom on this mower, it is extremely heavy duty and well built, having been through 10 years of unhealthy conditions.

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This is underneath the back axle, with a lot of stuff stripped out. On top of the HST unit is the hydraulic valves. You can see the big whole where the grass shoot goes through. The cylinder here is for the deck lift, I have no idea why it is so beastly. It is a monster. On the right is the lift pump for the diesel, and the fuel tank sits on top of that grey plate and is sandwiched between too rubber mats.



And this is the HST unit, showing the damaged fan. hope the fan hasn't done any permanent damage. I took this photo just before I started stripping the drain pipe out - that is why the clip is undone on the pipe in the middle.

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This is a photo of the big hole the grass comes through - looking in from the back of the mower. In this photo you can see all of the crap that is caked around the HST unit. I will scrape all this out and then give it a good wash. It is nearly impossible to clean this area without stripping the mower down, but if this is all that happens after 10 years and 1000 hours, I don't think there are too many problems. There is very little rust on the whole mower. If the chassis was more rusted, i would strip everything off it, engine included, and repaint the whole lot. But I simply don't think it is worth it. After all, it is a lawnmower!

You can also see the HST filter, I imagine this can be replaced by just popping the rear wheel off instead of the whole top. The big pipe in the foreground of the photo is the fill tube for the HST oil, and the pipes with the red caps are breather lines for the gearboxes. The flap that is covering the axle is the floor to the grass shoot, and this is being replaced as it is shot, and there is a piece missing as well.

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This photo shows the HST levers. These were really loose, and vibrated around a lot, with plenty of slop.

I had a look at the linkages, and it was a simple matter of tightening up a bolt on each one and they are back to as new with no slop at all. A million times better, and such a simple fix now the mower was stripped down. There are some naf rubber pipes over the hydro levers that have become discoloured, I will chop these off I think, and I will see if I can replace them but only if I can get the knobs off the levers. But I'm not really sure what the purpose of these levers is.

You can also see the primary diesel filter in this photo above the lift pump, I think I will replace this one for sure as I can't imagine it can be replaced without flipping the top.

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Here was another really nice easy fix - the throttle linkage. It was too loose and would not stay at top speed. Two minutes with some spanners and a good clean - and it is back to new. That was going to annoy me for ever if I did't fix it. You can also see the computer in this photo - a computer on a lawnmower! It seems in perfect order, don't think I will go fiddlign with it!

Right that is all the photos for now. Next jobs are to pick up the new parts from the dealer, and fix the mechanicals of the mower. At the same time I will continue to clean it up. Need to get hold of some grey paint and I will start touching up areas with a brush which I don't want to strip off.

Then I need to strip the radiator out and replace the foam strip, I think that is going to be an awkward job. Hopefully soon I will have a workshop manual for the mower.

Then I need to take all the bits I want sandblasting off to the blasters, and then drop them off at the painters. I'm going to get a mate to paint the panels as he will get a better finish than I will, especially as my workshop is a bit damp at the moment.

Then I will start putting it back together, new stickers and we will be ready!

Oh I need to order up some filters for the back end and drop the oil, the engine has already been serviced.

So far I am very impressed with how the mower has been designed, and it is much nicer to work on than the typical store bought ride on mower.

More later (I hope this thread will be useful to someone, even in the future who decides to do some work on a Kubota mower, they are all very similar).
 
   #5  

David_Kb7uns

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Joined
Aug 21, 2005
Messages
2,002
Location
Willamette Valley Oregon
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Kubota X 4
"You can also see the computer in this photo - a computer on a lawnmower! It seems in perfect order, don't think I will go fiddlign with it!"

The computer is the control box for the "Electronic Power Steering".

You should like the mower, have the G2160-60, has the 60 inch, same as on my BX2230 and it is like a sports car for mowing. Does well around trees and curves and the large deck makes short time of large lawns. In the spring doing over 4 acres every 5-6 days.

David Kb7uns
 
   #6  

J Dunne

New member
Joined
May 9, 2011
Messages
1
Tractor
Kubota G18 & John Deere 6430 Premium
Hi there Grrr,

How is the restoration proceeding?

I must say that I was very impressed with your attention to detail.

I too bought a second hand G18, they are a really well built mower.

Hope you are cutting grass at this stage?


J
 
  
  • Thread Starter
#7  
OP
Grrrr

Grrrr

Platinum Member
Joined
Jul 17, 2007
Messages
800
Location
Devon, UK
Tractor
John Deere!
Hi there Grrr,

How is the restoration proceeding?

I must say that I was very impressed with your attention to detail.

I too bought a second hand G18, they are a really well built mower.

Hope you are cutting grass at this stage?


J

Hi J Dunne

Yes I have finally got the mower back together and cutting grass daily with it :)

I'll finish off this writeup as soon as I have a chance.

Got it all stripped, replaced the broken bits, repainted bits of it (haven't got around to doing the bodywork yet), then put it all back together again!

Then I had a few problems with the cutting deck, firstly I needed to replace some of the idlers because the bearings were shot, and replaced the blades.

Then it seemed to vibrate a lot.

So I replaced the belts as well.

That made it vibrate less, but it still vibrates a bit and I still haven't quite got to the bottom of the vibrations.

I also had an oil link on the front shaft coming out of the mower gearbox, had to put a new bearings and new oils seals all around (and a new cap thing).

Other than that, it has been going well.

Kubota UK are quite handy, as are the dealers.

If you need a workshop (or operators) manual, I have them on PDF.

Jake
 
   #8  

edevelop

New member
Joined
Aug 13, 2011
Messages
1
Tractor
Kubota G18
:thumbsup:Hi Jake,

New member, I recently bought second-hand G18. Grass on acre site nearly 3 foot high. Cut thu it like butter, had to change PTO belts 3-4 times with spurious make as I did not have Kubota belts. Recently got Kubota parts so plan on doin a bit of work change deck belts that are in bad condition and look like they will go anytime so a bit of preventative work planned.

I note you have manual on a PDF, I would really appreciate if you could forward a copy. Your Kubota G18 surgery post was inspired, great work.

Regards,
Martin.
 
   #9  

Chrispyke

New member
Joined
Oct 15, 2012
Messages
2
Location
UK
Tractor
Kubota G18
Hi Jake

After many years of trying to cut damp grass with various makes of ride on mowers I have just purchased a Kubota G18 (2003 with 1000 hrs on the clock). You mention that you have the owner and service manuals in PDF format. If it is not to much trouble may I have a copy please. Looking forward to many years grass cutting with new machine. Regards Chris
 

Les aldrich

New member
Joined
Apr 13, 2013
Messages
1
Location
Northumberland
Tractor
Kubota g18
Hi Anyone,

I need to buy a replacement battery, I've tried the usual haunts but the sizes and terminals are different. Thanks Les
 
 
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