MMM Height Adjustment Knob

AceDeuce · Apr 27, 2006

The height adjustment knob for the MMM has a "Top" indicator which is supposed to keep the deck locked in the highest position so you can us the 3PH without raising and lowering the deck at the same time. Problem is, when the mower deck is attached I can't phyiscally turn the knob all the way around to the "Top" position. When the deck is off it works fine. I've tried adjusting the left and right side hangers but I have to go way outside of spec to get the knob to work correctly. THen the deck bangs against the frame every time I go over a bump because of the large gap.

Has anyone else had this problem?

Is there another adjustment that can fix this?

kevinj · Apr 27, 2006

( Is there another adjustment that can fix this?
)

Yep, It is all detailed in the owners guide. I had to redo mine as well. My 1850 has a bunch of other things out of adjustment but the mower top lock was fine!

gobbler · Apr 27, 2006

If I raise my deck and hold the lever in the up position with my right hand, I can set rotate the knob to the top position with my left hand. Try it.

AMR · Apr 27, 2006

I have had this problem, I tried turning that knob with all I had and it wouldn't budge. I found that the deck was not raised all the way up and actually the 3 pt arm tops in the back were not all the way up, even when the deck appeared to be, I could not turn the handle to top. I just moved the lever to bring everything up, the deck and the 3pt arms in the back, and the knobbed turned to the "top" indicater smoothly.

rdsaustintx · Apr 28, 2006

Raise the 3ph all the way up, then turn the knob.

imported_timalabim · Apr 28, 2006

I am also having this issue. I have looked at the manual, but am not sure which adjustment should correct the problem.
Any help?

Tdog · Apr 28, 2006

acedeuce & timala - - listen to rdsausins advice.

ericbx1500 · Apr 28, 2006

Did my 50-hour on my bx last weekend, which went smooth as silk. I then went and started to move some dirt and the first time I put the bucket in float position it work fine. The second time it would not lock in place, it only worked if I manually held it there. So I called the dealer and he told me more then likely the detent balls are rusted from condensation build up in the two caps at the bottom of the control valve (4 way). He was absolutely correct. I tapped the inner cap with a wrench and it started to work again. So I unscrewed both cylinders and let them soak in some penetrating oil. Then I cleaned them both up and lubed them really good. Now it works nice and smooth I did notice last season that it was a little tough to disengage the lever out of float position. Now I know why

This seems to eventually be a problem (though not a big one with an easy fix) down the road. Some people have drilled a little hole at the bottom of each cap so water can drain out. I would at least recommend unscrewing them both and lubing the spring up really good and put about three pumps of grease at the bottom of each cap. When I unscrewed mine there was only a little dab of white lithium grease on each spring. After I did all this the detent worked nice and smoooooooth better then the day it was delivered.

imported_timalabim · Apr 29, 2006

Do you mean to manually lift on the 3-pt? The 3-pt and the mmm are both on the same lift control are they not?

teachdocs · Apr 29, 2006

Sometimes, the MMM height adjustment knob can be placed into TOP position by clockwise or counterclockwise turning...other times, only by rotating from 1, 2, 3, 4, then top. The "steps" on the shaft are angled slightly and designed for one-way rotation.
Try raising 3PTH completely, then turn knob from lower numbers to higher, then TOP.

Mike_Lipke · Apr 29, 2006

Take those bad boys off again and drill a 1/16" hole in the bottom.
That lets the moisture out. The new ones already come that way.

ericbx1500 · Apr 29, 2006

( Do you mean to manually lift on the 3-pt? The 3-pt and the mmm are both on the same lift control are they not? )

Yes there on the same controll, No you don't manually lift the 3pt. When you pull your lever back to raise the mmm the lever automatically returns to the neutral position. But when you do this your actually not raised up all the way. Just pull the lever back again and you will see the mmm/3pt will raise higher. Now you will be able to turn your knob to the (top) position /forums/images/graemlins/grin.gif

imported_timalabim · Apr 29, 2006

Still can't get to TOP with the deck on. No problem without it.

rdsaustintx · Apr 30, 2006

( Still can't get to TOP with the deck on. No problem without it. )

Tim,

RAISE THE 3 POINT HITCH AND THEN TURN THE KNOB.

The knob controls the position of a stop under the deck links (which are attached to the 3ph).

Russell

imported_timalabim · Apr 30, 2006

I have tried several times to do this, with the deck all the way up, i can turn the knob down to 0 and up to 4 but can't get it to go to TOP. I tried holding the lever in up position while turning, still a hard stop at 4. The post above says there is an adjustment, but I can't figure out which of the mower deck adjustments would do the trick. /forums/images/graemlins/confused.gif

rdsaustintx · May 3, 2006

OK I'm stymied. Will have to crawl under and look at the thing. Will be mowing this weekend if it doesn't rain...

Russell

AceDeuce · May 3, 2006

I should have clarified earlier, but I'm in the same boat as Timalabim. I DID have the 3PH raised all the way up BEFORE turning the knob and I do have the MMM deck hangers adjusted so there is about a 1/16" gap between the deck and the hard stops welded to the frame (according to the instructions in the operator's manual). However, with the deck attached I still can't get the knob all the way around to "TOP". When the deck is off it works fine. I was wondering if there was a hidden adjustment somewhere, maybe on the knob linkage itself? I guess I'll have to mess around with it some more this weekend.

kkesler · May 4, 2006

I have this problem as well, except mine won't go to top even with the deck off.

kubby · May 10, 2006

I had this problem as well. The solution is just a couple of adjustments. There is a threaded rod with two 19mm nuts, visible from the rear between the right tire and the frame. These nuts adjust how far the MMM linkages lift when the 3PH is all the way up. Turn the nuts farther onto the rod and the mid-mount parts can lift higher, but only if the MMM support arms are not contacting the stops on the frame. If they are, the threaded angle brackets that lift the support arms must be extended (unscrewed a turn or two) so the arms do not hit the stops and prevent the mechanism from lifting as far as it has to to allow the knob to go into Top position.

I disconnected the retaining rings and clevis pins completely from the threaded angle brackets, then adjusted the 19mm nuts until the knob would easily go into Top position. Then I reinstalled the angle brackets, adjusting them by trial and error until they did not quite touch the stops at full lift and both ends of the mower were equidistant from the floor.

RED4x4 · May 19, 2006

I also had this problem, it would go into TOP only with the deck removed. After a lot of checking, I discovered the right side rear link was binding on stopper(see mower operator's manual page 14 fig.B), preventing the deck from raising all the way up. My solution was maybe a little drastic on a new tractor but it worked. I got out my grinder and shortened the sleeve on the inside of the rear link to gain clearance. I also shortened up the "stop" on the top of the stopper because it was hitting the main part of the rear link. While I was under there I also shortened up a couple of mounting bolts from the operators platform that were interfering with the rear links. I hope this helps. /forums/images/graemlins/confused.gif