problems with carlton kubota 4012

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stump-dude

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hi all those who own and want to own a kubota 4012.
im just trying to find out who has had any problems if any with the new kubota engine 4012. As i have had a few not large but irritating problems.
the engine whitout being engaged vibrates like crazy, and it looks like i have to tkae it in to the dealer to be looked at. the vibration is basically ripping the machine apart, ive had to weld up the belt cage(from engine to jack shaft) twice and then the third time, weld it with re-inforcing. ive replaced my rain guard on the air filter 3 times, and had to disconnect the safety switch next to the key ignition until i found the vibration had broken a connector to the oxygen sensor( so that was an easy fix). replaced the belt setup with the free upgrade kit. but i was just wondering if anyone else has had these types of problems? many thanks!
 
Sorry to hear about your problems, but yet again it seems we the buyer are the field testers for a new product, when will manufactures properly field trial there products ''before'' they hit the market!

I read about the new kubota 4012 less than a year ago, is that really enough time to, design, test, re-test,re-design etc etc?
 
Hey Stump-dude,

When I demo'd a Kubota 4012 last July at the Carlton factory it was the smoothest running machine I'd ever seen. What was yours like when it was new? Has it always had a vibration problem? Something must be wrong or broke that you can't readily see, I don't think it was a design problem, at least the one I saw was really smooth. But, maybe some of the other guys that got them like Bigstumps will put in their reports.
Hope it's an easy fix, yours should still be under complete warranty, engine and rest of machine. Let us know what you find, it is still my choice for next machine.

Stumper63
 
No vibes at all. Had my belt drive system replaced to an updated one by the factory - the Kubota is one of the smoothest diesels I've ever been around. Pushing 300 hours.

Are your vibes there without the wheel engaged??? At idle?? At full throttle?
 
Any one with a 4012 had trouble with bearings on jack shaft and cutter wheel, if so what did you think caused it?

Appreciate any replies:)
 
hey creeker, how many hours do you have on your machine? ive got just under 500, and no real problems yet, but iknow im going to have to replace the cutter wheel bearings real soon, reason: sucking up planting rope into the bearings. my one bearing has lost its grease nipple. my wheel is experiencing alot of wear, ive added extra material by wire welding in the heavy wear areas. also looks like i will need to replace some of the bushings that move the cutter head as it is getting sloppy.
 
Thanks Stumpdude for reply,

Machine done bee's d...k over 100 hrs.

Looks like appreciable wear on all four bearings, jack shaft and wheel, having trouble working out what has worn them so fast.

It certainly isn't grease, it is greased (20 pumps/bearing) to purging every day of use and looked after pretty well I would say.

Our hard wood stumps are heavy duty timber but I was under the impression that the machine was over-engineered to handle them.

Generally it is a good machine and I love the wireless remote, makes for improved safety, the KUBOTA is super smooth and fuel efficient, 2 to 3 litres per hour when working. Don't like radiator blocking with bark/wood chip and affecting air flow. Multi V belt from engine to jack shaft lasted about 90hrs, at Aus$180 is an expensive problem.

I'm certainly not happy with the maintenance costs at this stage of its life!

The bearings are going to be in the $100's each.

Our local distributor, RED ROO are good blokes to deal with and I hope they do the right thing by me in this case.

PS...Had relative here in Feb' from near Toronto, he hunts over BC way, looks like beautiful country.

all the best, CRKR.
 
Creeker,

I don't understand how you see wear on the bearings. Usually you will hear them roar real loud or you can move the shafts by hand once they have wear in them.

100 hours is way low for bearing life - something must be going on. Grinding in a ton of rock? Dull teeth? Some kind of abrasive soil getting in them?
 
Thanks Bigstumps for interest, good questions:-


I was giving the machine a real good going over recently and checking belt tensions, greasing, tightness of shaft collars etc etc. (114hrs since new)

I'll add that when turning the cutter wheel over manually in the previous week that that it had a bit of a clicking noise coming out from the jack shaft/belts/cutter wheel area. Couldn't really ID it, but seemed like bearings. But could have even been a bit grit stuck in a belt.

Anyway I checked the poly belt, (jack shaft to cutter wheel) and saw that it was a fair bit loser that usual. When I squeezed the belt together I could see the top right hand bearing moving and feel it. Ie the shaft and inner bearing surface was moving inside the outer bearing surface. I suppose it had < 0.5 mm play/movement.

I describe the top right as being the bearing on the j/shaft nearest the multi V belt drive from the motor pulley.

I've tightened the poly belt and its taken that movement out due to the pressure applied by the belt.

I then checked over the bottom bearings and the bottom right one (on the cutter wheel shaft, furthest from belt) has a steel cover bolted into the end of the shaft which, when the weight was on the cutter wheel, by lowering the whole engine/cutter wheel, that the cover moved upward about 1mm.
(25.5MM = 1 inch)

Yes been cutting some tough hardwoods, yes, hit rocks, yes hit odd piece of steel.

Abrasive dust - we are in a very dry area last few years, have been working constantly in super heavy dust, but rarely in sandy areas.

Greasing as I said, went to local bearing supply and got the best high speed grease they stocked.....it is used EVERY day to purge all 4 bearings.

Anyway, will get it checked over by local mechanic who is clued up on this sort of thing, I'm hoping he will tell me its just a bit of wear within reasonable tolerances, but I doubt it.

Have ordered 4 new bearings.

Expect to fit them this week.

regards CRKR.
 
GR8 SCOTT,

In AUS. the dealer is RED ROO. They import the Carlton machines, rename them and sell them.

I have spoken with them, they are good to deal with generally speaking, I haven't broached the subject of 'warranty'.

Machine under 12 months old, 116.6 HRS today.

Ps .. been working it today, bit of vibration but nothing very bad, bearings not hot.
 
Creeker,

That makes sense - squeezing the belt and watching for movement. You shouldn't see any.

The bearings on my Carlton are way larger than those on my old Rayco - and are the style used on my 672 Vermeer. Odd that they would be out with such low hours.
 
I have decided to try the following in an effort to get longer bearing life when the new ones are fitted:-

1. Grease during the day, say every hour.

2. Run belts not as tight.

3. Slow slew speed on cutter wheel down.

4. When transporting machine put less weight on cutter wheel in trailer, sitting on an old 13" car tyre and three folds of carpet at present.

5. Drink more beer and say 'bugger it, she'll be right mate' !! :givebeer:

Appreciate help, thanks.
 
Red roo sp4012 bearings.

So now the machine is about 40 hours down the track and on the original bearings.

Had covers off y'day and can see play in same, maybe same or fraction worse.

My local RED ROO (CARLTON MACHINES RE NAMED FOR AUS.) dealers had been s/t Carlton in US who reckon it was impossible for the bearings to be worn out.

Also advised me that I was 'over greasing', and the manual instruction of daily means 5 or 6 hours work.

So now grease very 4 hours or so and hopefully will get some more lfe out of them.

The bearings at around Aus$450 each X 4 are a very expensive repair, will hope to not have to spend that sort of money for a while!
 
creeker im not familiar with your machine but in previous post you say u put 20 pumps of grease in to the bearings, thats a #### load mate, id say with all that grease ur pumping in youve up set the bearing case and some dirts got in there.

just my 2 cents
 
G'day Treeops.....

Manufacturers Manual says "Grease jack shaft bearings daily, these bearings should be purged using grease every day"

Ditto...cutter wheel bearings.

When I s/t Red Roo they indicated that after consultation with Carlton in US that every day was say......4 or 5 or 6 hours machine time.

If my machine did 1 or 2 hours in a day then I was greasing these bearings to purging.

Have been told not to grease so much, so now grease to purging every 4 hours or so.

Grease gun is hand operated, takes pretty much exactly 20 pumps to purge, another owner nearby also found that number of pumps on his SP4012.

Anyway, will work on!

regards, Creeker.
 
G'day Treeops.....

Manufacturers Manual says "Grease jack shaft bearings daily, these bearings should be purged using grease every day"

Ditto...cutter wheel bearings.

When I s/t Red Roo they indicated that after consultation with Carlton in US that every day was say......4 or 5 or 6 hours machine time.

If my machine did 1 or 2 hours in a day then I was greasing these bearings to purging.

Have been told not to grease so much, so now grease to purging every 4 hours or so.

Grease gun is hand operated, takes pretty much exactly 20 pumps to purge, another owner nearby also found that number of pumps on his SP4012.

Anyway, will work on!

regards, Creeker.

Yeah, it takes about 30-35 pumps to purge the bearings on my Carlton 7015.

That's why I got a cordless gun. lol
 
Sp4012

G'day GR8SCOTT,

Know where you're coming from!

Has got to be a good thing that cordless greasegun.

Does it take the cylindrical (small) tubes of grease, or are you fitted up to a larger grease can of some description?

rgds, CRKR.
 
G'day GR8SCOTT,

Know where you're coming from!

Has got to be a good thing that cordless greasegun.

Does it take the cylindrical (small) tubes of grease, or are you fitted up to a larger grease can of some description?

rgds, CRKR.

It takes the regular size grease cans that you can buy at any auto parts store. I like the Lucas Red & Tacky.
 
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