RCK48-18BX Level Issues

[locke-j]

Hi Everyone,

I have a BX1880 with this deck. I decided I'd get it properly leveled when I put it back on for the spring, and am following the manual's process, but am running into issues.

The biggest problem is the front of the deck is too high. In the manual, it states it should be level or up to 0.2" lower than the back and the adjustment for this is on the front link. I loosened the bolts on the front link to the point where I have no threads remaining and it's still too high. I have the side-to-side adjustment bolts on the back hangars basically maxed out in an effort to raise the back to compensate, but it still isn't enough. Last I checked, I'm nearly a 1/2" off measured from the tips of the center blade.

Any ideas? Is there possibly an adjustment that I'm missing that's causing the back to be too low? There is a rear link adjustment that I haven't messed with because the manual suggests this is just a stop, but I wonder if that has anything to do with it. It's a fairly new machine that I'm pretty confident I haven't bent anything on. I just want to learn what I'm doing wrong!

Appreciate any advice!

 

[JWR]

"Bolts on the front link?" I assume you mean the nuts on the front link , right and left. Each side having 2 nuts so it is a lock nut configuration. The only adjustment to the length of the parallel linkage (and to blade leveling) is those nuts. I say DECK leveling but it is really the BLADE that matters, not the deck per se. Rotate your blades so that the one close to the outside of the deck (on the side you are on) is pointing fore and aft in line with the tractor frame. Going by your manual, the goal is to have the front blade tip be somewhere between 0" and 3/16" higher than the rear blade tip. Accuracy for measurements of level in the 1 to 3 16ths of an inch range with a mower deck is far fetched in my opinion. The concrete probably varies by that much! Of course you need to be on a flat enough surface like a garage floor so you can measure well.

I suggest that you put the anti-scalp rollers in pin positions that cause your blades to be very close to "flat" (same distance off the concrete front and back blade tips) first and then adjust the nuts on the parallel linkage to take up any slack after that. Once the parallel linkage nuts take all the slack out of the linkage (and match left and right) everything should just be snug, nothing loose, with the deck resting on it's wheels. Tighten the nuts. You should then be able to raise the deck hydraulically and go back and measure the clearance to the concrete of the front and back tips of the blade with the anti-scalp wheels up in the air. This is not going to be some microscopic measurement but while the deck is raised the front and back tips of the blade should be roughly the same height off the concrete.

By the way I have found that the leveling of the plane of the blades is surprisingly sensitive to the adjustment nuts on the parallel linkage. That seems to be true of many different models of Kubota decks. You should not be at the extreme of the threads on the linkage -- if you are, there is something wrong.

Now your description to us essentially says "yeah but that doesn't work. The front of the deck is too high."
1) Make sure you are talking about the blade not the deck. My first suspicion is you were paying attention to the deck rather than the blades.
2) I agree it is unlikely that your parallel front linkage is bent -- those are pretty stout.
3) You probably need to go back and put the rear hangars in some intermediate position. Whatever your manual says. You should not/cannot use the rear linkage to alter the front/back angle of the plane of your blades. Only the nuts on the parallel link do that.

Please let us know what you find from here on.

 

[locke-j]

Thanks for the detailed reply.

As I mentioned, I'm not measuring from the deck - I'm measuring from the tips of the center blade. I'm using a blade height measuring tool to do that. Reading both your response and the manual's, I'm finding it's saying to use the right side blade, though - not the center. I'll see if that measures differently.

You're correct, I'm working with nuts, not bolts, on the front linkage and that's what I'm running out of threads on. However, my manual states the front blade tip should be 0-.2" lower than the rear blade tip, not higher. At the moment, I'm maxing out the threads on the front linkage before I even get it level.

I am doing this on concrete. I have a patio I'm using for it because it's very level. The garage concrete has a slight pitch to it.

I'll set the rear hangar adjustments at the middle of the thread again, then I'll use your suggestion of resting the front on its wheels to get the right pitch and tighten the linkage from there. I'm hoping simply starting from scratch makes a difference.

 

[JWR]

Understand. I assume you are using the Kubota BX mid mount mower and the manual I have shows it being used with either the BX1800 series or the BX2200 series tractors. I need to go back and hunt my manual but it had the little discussion about "X minus Y" measurements with X being front and Y being rear blade tips. I interpreted it to be saying the front tip should be higher. (?) As a practical circumstance I think "Level" with zero difference front and back is good.

Yes, I would hope that starting over from scratch will make the difference. Hard to imagine anything is bent.

 

[locke-j]

Understand. I assume you are using the Kubota BX mid mount mower and the manual I have shows it being used with either the BX1800 series or the BX2200 series tractors. I need to go back and hunt my manual but it had the little discussion about "X minus Y" measurements with X being front and Y being rear blade tips. I interpreted it to be saying the front tip should be higher. (?) As a practical circumstance I think "Level" with zero difference front and back is good.

Yes, I would hope that starting over from scratch will make the difference. Hard to imagine anything is bent.

Yes, the X/Y thing is in my manual and it takes a second to interpret, but I think it means the front should be 0 to -.2 compared with the back.

I think the RCK48 was only available with the bx1800 series, but the manual includes the RCK54 and 60 which were available for the other machines. The instructions and leveling measurements are all the same between them - though the 60" unit has balancers to adjust. I'll probably wait until the weekend when I can devote some more time to resetting it and trying to get it right.

One other thing I didn't mention is I verified tire pressure is to the book front and rear. I know that could mess with things.

I am fairly certain tightening the nuts on the front link raises the front, but when I look at it part of me wonders if I'm crazy and it actually pulls it down because of the way the link is shaped. When I play with it I can verify.

 

[JWR]

Your photo is helpful. Yeah, I agree that "the more the nuts are tightened towards the axle the more the front of the deck gets raised." If things are not resolved when you get a chance to 'start over' this could be a baffling situation.