C-161 Keeps throwing drive belt Part III

[rplosnak 0]

I have a C-161 Hydro with single Kohler 16 throwing drive belt.

Replaced new so far: idler pulley, spring tensioner, and 4 new ISO mounts.

Belt is correct size at 84". 83" TOO small.

Also when lever is pulled up to disengage hydro, it will STILL drive fwd and reverse!!

Can someone provide photos of clutch/lever mechanism? Don't know if prior owner did something and got things turned around.

Guy I bought it from said he put on new belt and the rubber burning smell was due to new belt being broken in!

I found out belt was riding off the idler pulley and running between belt guard and side of idler.

Belt completely flies off with guard and footrest off.

Don't know where to turn now.

Already put in a new/used transaxle that had bad seals. Owner said rearend was just serviced and was ready to go. Found out he had oil level down below the axle so as not to leak out!

I don't want to give up on this one, and I know with the great help from this site, I can get this thing right.

[smoreau 658]

My 417 had the same issue last week. It was the tensioner arm that was tweaked a little and under load it would ride up and over the pulley on the arm. I took a crescent wrench and straitened the arm and all is good again. With the guard off you should be able to see what is the issue.

[Don1977 605]

I have never had a hydro, It the belt won't stay on I would pull the hole idler assemble apart and check for ware on shafts, bushings, idler arm. Could be too much loose motion in the assembly causing the belt to come off.

[Callen 64]

If you have 1/8 inch gap between the drive pulley and engine block and the idler is a flat pulley ( no belt V groove) and the shafts and bushings aren't real loose.I would suspect not having a thick enough spacer on the idler mounting bolt. Can you post a pic of the inside of the belt guard?

[Trouty56 567]

The stock belt is 5/8 X 84...I have a C-160 hydro with the same belt size and the hydro would continue to run disengaged. I used a 1/2 X 84 and that stopped it. Maybe it is because it is not a Toro belt but I don't have the funds to test sizes with OEM equipment.

Another thought is with the 1/2 inch width belt the idler pulley will tuck in closer to the rear pulley and keep the belt on....

Edited November 18, 2012 by Trouty56

[Don1977 605]

I think you may have the wrong idler pulley.

[SousaKerry 503]

It may be that the belt guard is wrong or is missing parts. The belt guard keeps the belt from rotating while the tension is off. However I would check that all your pulies are in line with each other put a strait edge across all three. Also check the slot in the disengagement lever. I had one that was having problems and the slot was worn into almost a triangle shape, it should be a strait slot.