lift up the tilting seat. look in the cavity underneath. there should be a decal/plate with the mfgr's name and the full model number and serial number. Post back here with that info so we know WHICH machine we are dealing with. Will help greatly to find an answer.

Sorry. Meant to include it. Lawn Machine 42 inch, 17.5 hp,
742 AL. Model # 13an772g729 (2007)

1) did you buy OEM replacement parts or aftermarket parts? 2) did you have and follow both the operators manual and parts list for that tractor?

In looking at both, the procedure seems pretty straightforward - unless you got a short/long replacement deck belt and then started to try to compensate for same...

Next time, ALWAYS take pictures before taking such things apart and relying on memory... (yeah, I know it doesn't help much now) But, look at the diaqgrams in the owner's manual, they have some detail on the location and hookup of that engagement spring.

I did purchase OEM replacement parts. A picture is a great idea but the spring broke and came off the machine. I replaced the spring based on my interpretation of the diagram. After the initial installation the belt was rubbing when the PTO engaged. I removed the spring tried several other options and each time the belt was too loose. I put it back as I initially installed but now the belt is way loose. I am at a loss as to what to try next. How do you go from rubbing tight to falling off the pulleys loose?

1) what spring broke? Pls identify by item number and parts list page.

2) Just where was belt rubbing when first installed? How could it possibly get longer?looser in the 2nd installlation?

I think I am correct when I say that the actual belt tension is made by the spring on the cable. be sure that the cable is on the proper side of the little round brake rod that it passes by. The idler arm itself on these get worn egg shaped at the mount and can bind. Plus the arm itself has 2 mounting holes- one for a 38 and one for a 42. The parts diagram will reference where the brake springs go.

I went to mtdparts to look at the deck diagram, much better than the ops manual. My model # is 13an772g029 the closest thing I could find is the 13an772g729 that I mentioned earlier. They are close but not exactly the same which I think has caused some confusion. Do you know where I can find the 42 inch deck assembly for my model. I am trying to position both the tension pulley spring and the spring of the PTO cable.

this may help... go to the link noted and download both a fresh operator's manual and a parts manual for your machines. Use your computer's ability to enlarge images to get better detail on springs in question.

to download, you will need both your full model number and serial number.

Here is a link that might be useful: manuals download

Thanks for the reply. I found the parts manual for my model, it does look a little different but closer than the previous one I had. I hooked up the pulley tension spring and it looks ok. It appears that the spring on the PTO cable hooks to a screw with spacer under the pulley on the right side of the machine. I located the screw but I can't stretch the spring far enough to hook it on. Two questions: 1. Have I found the right place to hook it? 2. If so, how do I stretch it that far?

did you follow the particular view for your sized deck? the configurations ARE different.

This seems hard to follow. The spring on the PTO cable itself will hook to a hole in the idler arm. Hook the spring in the arm and then the outer cable into the holder to the rear. The other springs are actually brake springs on the deck. Is this different than what you have found?

I thought that as well but when I hooked it up like that the belt was way loose. I enclosed a link to the diagram that I am using. There are only two springs; pulley tension spring which I hookup and the spring on the PTO cable. The spring on the PTO cable is confusing me. It is part # 27 on the diagram. I really appreciate you looking at this.
http://www.jackssmallengines.com/Jacks-Parts-Lookup/Model-Diagram/MTD/51008/20765

tomplum, You are absolutely correct. I went back and re-connected as you suggested. The belt was way loose but I discovered that the brake control rod was in the wrong position. Once I adjusted that the PTO engaged correctly.

Thanks for your help.

I have a Yard Machine MTD 42 inch cut the model number is 13A2775S000 I am in need of a diagram to show where the tension Springs hook. I am a woman and I am trying to do this myself. Thanks

I've not seen usable diagrams out there for MTD. I could look in what manuals I have though. So which springs have been removed? Are we in the transmission drive section or cutting deck? Pics are great!

I'm in need of same above with no way of finding model number because the orginal seat is gone.

I have a model# 13am775s000 yard machine 42 inches. I put new blades on, and a new deck belt. Now idler pulley will not engage. I have changed these things before with no problems. My PTO cable is not broken, but when engaged the idler pulley is hard to move. Disengaged the pulley moves easily. I need help, or should I buy a new mower?