F3680 mower deck height adjustment

[Rip]

Guess I replied to Neil when question was not really directed to me....but Johncar's description of sliding uncontrolledly sideways is what I was referring to myself and thus the all-out effort to prevent such reoccurrence.... wheel spacers do not address that by themselves, but do greatly increase the overall stability and control of the machine in extreme conditions. Up/Down, Diff-lock and 4WD lock always in such conditions....and keep that engine running!!

Cheers and Good Luck!!

 

[OrangeRidge]

Many thanks indeed for the detailed replies to my concerns

This is the new machine : http://www.tractorbynet.com/forums/...g/378300-back-orange-kubota-f3690au-72-a.html

They took longer than expected to un-crate and deliver , as it appears I was number 7 of the 10 they were bailing out of . Consequently I'd just cut all the grass with the Hustler , only to be phoned an hour later to confirm a time to bring it out . Now I'm patiently waiting for the grass to grow ( winter's begun ............. ) to have a decent go . The cyclone Debbie was quickly through these southern parts and only gave us 12-14 inches here . More wind than water.........

Recommended tyre pressures ( 20psi front : 35 rear ) are too high and bounced all over the show so I'm going with 17psi in the 24x12x12 and 25psi in the small ones . 30psi in the castors .
I noticed that the rims are 12x10.5 ( 24x12x12 tyres ) as per the BX18## rears . It's easy to find spacers for BX 12x12 rims , but this F3690 has smaller lugs and bolts ( same spacing ) and rim holes that don't take a BX size stud/bolt size .......... that's annoying . Check the photo in the above link to see .

 

[johncar]

Nice mower there Neil, congrats, I hope that you like it and it does everything you expect of it. I still love mine despite the odd scare but we are talking extreme hill work here obviously beyond their design. I haven't had a repeat while using the diff lock so that is good.
If you get on to any wheel spacers I would appreciate it if you would let me know how you got on. I was thinking even about 50mm per side would give just that bit more safety margin but just haven't got around to doing it.
Yes the tyre pressures are probably suited for running over clean parkland. Lower pressures should help for grip and less bounce and in my case less punctures.

Great advice there Rip thanks also. Never though too much about the engine / seat kill switch. Mine is still connected but has never hinted at stalling while I am in the seat. Always a first time and I guess under load it would stop very quickly should I slide on that seat in any way at the wrong time.

 

[OrangeRidge]

A quick look at unit width (outside of tyre to tyre ) for comparison :

BX2360 1145mm
B2920 1245mm
B3030 1365mm
F3690 1370mm

Combining the low centre of gravity due to the 24x12x12 tyres and the high weight counter-balanced on the arms whilst cutting , the F3690 was more stable than I first thought when looking at the ride height of the operator's seat .
Got to cut a couple of acres yesterday evening and was very pleased with the cut quality . Had to watch the rear with its swing out though ....... Although the driving unit bounces a bit , the deck ride is as smooth as could be
Had to reduce drive thrust on uphill turns a bit to avoid 24x12x12 wheel spin , but the small rears behaved very well and I never lost traction/control . The engine revs stayed constant at 2800rpm ( my selected rpm , but will go 3170 )
uphill and down , through thick and thin grass . The power is just awesome ! Nothing on this machine labours under inadequate available power . I'm smitten !

 

[johncar]

Thanks for the info re your tyre widths. Yes it is a good stable machine. I think I just got lured into thinking that it was invincible and just go anywhere until the wheels just wont drive but there is that one situation I have to be mindful of.

So running up a steepish embankment of around 25 - 30 degrees not quite square on and at the top of the embankment it levels off fairly quickly. So when I just went up slightly over the edge onto the flat slightly angled before backing down, it was then that the machine got out of control and skidding sideways down the slope. It has never done that thing since though with the diff lock engaged so it is just habit now and anything beyond about 25 degrees the difflock is engaged.

FYI, I found that for my personal situation here the standard Kubota blades to be a bit aggressive in throwing the grass out which tended to cover everything in grass clippings including me. So I opted for the ASP equivalents who are based around the north side of Brisbane and happy to post them out. Their blades still throw the bulk of the clippings clear but with out the hurricane. I think that they may be a bit stronger and cheaper as well.

BLADE KUBOTA 72" STEPPED