Woods RD7200 mowing deck problem

[phawes]

I have a Woods RD7200 mowing deck with a problem. When running, it vibrates enough so that stress cracks have formed in the deck structure and the belt shields. Belts do not last long. I believe that this is caused by the idler wheel being out of alignment with the drive and blade sheaves. Placing a straight edge on the idler seems to confirm this. I have replaced the idler-arm-pivot bushing (part #35145), but there is still considerable play (i.e., slop) in the idler arm. Spring tension forces the idler arm to a position where the idler wheel is misaligned. Is there a common repair for this problem?

 

[KennyV]

You should not have a LOT of vibration...
Check for bent cracked blades, loose bolts and tweaked pulleys, especially the drive pulley on the gear box. If something is out of alignment or balance it will eat up belts.
If your tensioner is not free to move you can use bushings and spacers to place things in alignment.
With 3 blades and pulleys plus a long belt and idler(s) there is a lot of inertia to overcome at start up, you should feather in your PTO drive, with engine RPM low, to avoid over stressing things. KennyV.

 

[GIJOE]

Remove the three blades and run the mower at cutting height. If the vibration has disappeared install new blades. The idler pulley is a flat grove pulley and tensions from the back side of the belt and is usually wider than a v-grove pulley. So putting a straight edge across the pulleys will make it appear it is out of alignment, but it is actually just sticking up a tad above (and below) the others.

Joe

 

[phawes]

KennyV-

Thank you for responding. The tensioner IS free to move, but perhaps the pivot shaft is worn because the idler is definitely out of alignment. The entire arm is quite loose even though I just replaced the bushing. Where can I place the bushings and spacers so the the idler is twisted back in place?

You should not have a LOT of vibration...
Check for bent cracked blades, loose bolts and tweaked pulleys, especially the drive pulley on the gear box. If something is out of alignment or balance it will eat up belts.
If your tensioner is not free to move you can use bushings and spacers to place things in alignment.
With 3 blades and pulleys plus a long belt and idler(s) there is a lot of inertia to overcome at start up, you should feather in your PTO drive, with engine RPM low, to avoid over stressing things. KennyV.

 

[phawes]

Joe-

I appreciate your advice. I realize that the idler pulley is wider than the drive v-grove pulley and the strait edge will not intersect. But, the idler is not PARALLEL. The idler arm has excessive play at its pivot. If I lift up the end of the arm under the idler wheel about 1/2-3/4", the idler pulley is aligned (i.e., parallel).

Paul

Remove the three blades and run the mower at cutting height. If the vibration has disappeared install new blades. The idler pulley is a flat grove pulley and tensions from the back side of the belt and is usually wider than a v-grove pulley. So putting a straight edge across the pulleys will make it appear it is out of alignment, but it is actually just sticking up a tad above (and below) the others.

Joe

 

[windy acers]

BLADES ARE PROBILALLY REVERSE THREAD

 

[KennyV]

Can you post a picture of the idler and arm & its attaching hardware... I have seen that deck but do not remember just how it attaches...
I reworked the tensioner on my 7foot LandPride rear finish deck a little before I was happy with everything. KennyV

 

[phawes]

KennyV-

I will take a picture, but it will take a couple of days. The mowing deck in a pasture some distance away from my home. Today, I decided to bend the arm to see if I could get the idler wheel aligned. The lever does not bend, but it does break. So, the picture will show that damage.

Paul

Can you post a picture of the idler and arm & its attaching hardware... I have seen that deck but do not remember just how it attaches...
I reworked the tensioner on my 7foot LandPride rear finish deck a little before I was happy with everything. KennyV

 

[WH401]

It sounds like your problem is that the idler, or some other pulley in the belt route, is out of alignment/or some other type of problem, and that the blades are out of balance, and or either cracked/damaged. Having one of the pulleys out of alignment shouldn't generate enough of a vibration to cause stress cracks in the deck. However, that would definitely cause the belt to be eaten up faster. The deck cracks would have to come from something major as that deck itself is pretty thick. I think most likely you'll find it's the blades. Take the blades off and run the deck empty, just as another poster suggested. That way if nothing else you will at least get one possibility off the list.

 

[have_blue]

The idler rarely causes vibration. Sometimes the idler will seing rapidly back and forth on the pivot, causing a bad vibraiton. That's pretty easy to see, however.

1 or more blads shafts could be bent, pulleys could be warped or not concentric with shafts.

Did you ever try to run it with the blades removed to see if it ran smooth? That's also a good opportunity to peek at the shafts and see if they wobble. Bent shafts will smooth out once the blades are removed, but you can usually see the wobble.