MTD Yard Machines problems.

Santa Chas

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To shorten the story I built this lawn tractor. Turned every nut and bolt on it. It is a 2007 MTD Yard Machines 15.5 B&S 38 inch cut mower. I am having two issues and cannot figure out the root cause.

Problem 1, BRAKES. Lawn Tractor wont stop. Took apart the brake assembly on the rear axle. Found the little pistons were frozen. The disc and the small pads looked okay and they were about 3/16ths thick and smooth as was the disc. Freed up the pistons, sanded the pistons and bores smooth and re assembled the brake assembly. Still don't stop. Not sure if this has the correct spring on it. It is not too hard to hook it up. Just a pair of vise grips on the end to pull it to connect to the rod is all I have to do and there is not much resistance. Should this spring be about 4 inches long and about 1/2 inch thick and the spring size be about 1/16th in diameter? Should this Lawn Tractor be locked in park with the brakes set? When I stop the tractor and put the lever in PARK, turn down the throttle and shut the tractor off when it is in neutral the tractor rolls freely. If I leave it in gear it stays in place. Is this normal?

Problem 2, Deck Blades. These do not ever stop all the way. Only on idle do the blades stop. Give it a bit of throttle and the blades begin to move. I have had the deck off and looked at the braking system on the deck. The pads hit the pulleys like they should. It appears there are two springs on this cutting deck brake system. One under the right blade pulley and another on the brackets near the middle right. In addition there is a spring that is hooked to the PTO cable and this is also hooked up (replaced the PTO Cable) and it works.

These are the only two issues I have. The tractor works superbly. This tractor was purchased cheap and needed some items fixed. One being a cracked in half dash on the lower left side. I installed a temporary plate to solve this problem but when I drove the tractor the hood always seemed to lean right. Another was the nose/grill piece was split by the two lower bolts. Craigslist netted me a parts tractor. It was a 2008 16.5 B&S 42 inch cut model which looked the same as my mower. I pirated the parts for my mower from the parts mower. Having nothing to do I decided to strip the parts tractor down to a rolling frame. Thinking it was time to install the good parts on my tractor I took mine apart. Well, upon inspection I found the main frame on mine was cracked in half by the foot brake pedal. So now both tractors got stripped down to bare frames and this huge pile of parts was gone through. The best of the best went in one pile, the bad in another pile. Every bracket, pulley, spring, nut and bolt, body panel etc was looked over and cleaned up. I re assembled the tractor and have been using it ever since with no issues other than these two. Since I never had one of these tractors new I do not know every characteristic of them so any help I would be grateful to get to assist me in getting this tractor 100% right. Thanks in advance.
Chas.

Here is a picture of this tractor as it sits now.
 

bertsmobile1

Lawn Royalty
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Nov 29, 2014
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:welcome:

Nice job.
The brake has two adjustments.
The bolt in the center of the actuating rod ( the bit that pushes on the pins) is the brake adjustment.
Tighter = harder
On the rod connected to the pedal is an adjuster nut and spring.
You use this to adjust when the brake gets applied with respect to the clutch being applied so you are not declutching while you are braking.

go tohttp://www.mymowerparts.com/pdf/MTD-Service-Repair-Manuals/ and download your manual.
The Must have book 3 or the 700 series depending upon your model umber which you have not supplied which makes giving acurate & detailed information difficult.
OR you can google Must have book 1 lawn tractors and see if you can find one on the web

MTD used funny size belts and generally blades not stopping is because the belt is too tight or the blade brakes are beyound use as the pads wear and the spring looses its tension.
When adjusted prperly the brake should have about .100" to .050" clearence from the pulley.
 

Santa Chas

Forum Newbie
Joined
Jun 16, 2016
Threads
2
Messages
4
:welcome:

Nice job.
The brake has two adjustments.
The bolt in the center of the actuating rod ( the bit that pushes on the pins) is the brake adjustment.
Tighter = harder
On the rod connected to the pedal is an adjuster nut and spring.
You use this to adjust when the brake gets applied with respect to the clutch being applied so you are not declutching while you are braking.

go tohttp://www.mymowerparts.com/pdf/MTD-Service-Repair-Manuals/ and download your manual.
The Must have book 3 or the 700 series depending upon your model umber which you have not supplied which makes giving acurate & detailed information difficult.
OR you can google Must have book 1 lawn tractors and see if you can find one on the web

MTD used funny size belts and generally blades not stopping is because the belt is too tight or the blade brakes are beyond use as the pads wear and the spring looses its tension.
When adjusted properly the brake should have about .100" to .050" clearance from the pulley.

Thanks for the info. I went to the MTD website and downloaded the owners and repair manuals. Im going to sift through it. Thinking of just ordering up new brake pads (or as the You Tube video I saw called them 'PUCKS") and also order up some brake pads for the deck pulleys and just go the new route. I'm not sure where to order these parts, Jacks?? I realized when I spoke of the rear brakes and this questionable spring I was talking about was not the spring on the brake or caliper assembly if you will. It was the one that hooks to this assembly and to the rod under the mower. It seems weak to me and I am wondering if it is the correct spring? Its about 4 inches long and is about a half inch thick and the spring is 1/16th diameter. Since I had a pile of parts I thought maybe I installed the wrong one? I have extra springs from the build. Does anybody sell brand new springs for these tractors. I think there is like 5 total and maybe it would be better to have new ones? I have been looking around and pricing new tires as two on my tractor have plugs. The best bargain I can find is Carlisle Turf Savers in sizes 15X6X6 and 20X8X8 already mounted on correct gray powder coated rime brand new for about $185.00 plus tax. Since I was rebuilding this one fron the ground up I installed new MTD blades, MTD belts and a new battery. I also retrofitted a bagger system on this one from a mid 90s MTD tractor. All it required was a couple of pieces of Aluminum angle pieces drilled out and installed on the rear corners of the frame under the seat and a new elbow and it works just like new. Over the winter I want to find a set of body 3 body panels for this mower and media blast and paint them and put them on along with the new tires and perhaps the new springs if I can get them still? I want this mower to last a long time and the labor part does not bother me as I enjoy spinning wrenches. Just trying to save money. Keeping an eye on Craigslist for another mower like mine that does not run because MTD does not sell body parts. I'm a stubborn old man and cheap. I won't buy a new one.
Chas.
 
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