Drive Belt question

[dawgn86]

Model 917.203900....2014 with Briggs 22 hp with RS 800 transmission

my mower has 4 drive pulleys and I am having an issue with the drive belt coming off. The pulley its coming off from is the smaller back one near the transmission. It has a belt keeper on it and I have it bent down as far as I can. I never comes off while moving, only after I stop and back up to cut grass near curb or flower beds.

It takes 30 seconds to put back on, but would prefer it to just stay on like it should..any suggestions as to what could be causing this?

Thanks

 

[ILENGINE]

Make sure the transmission support brackets are still attached. If the bracket is not connected will allow the transmission to pivot when starting and stopping. Also will cause cracking at the connection points at the frame/axle area

 

[dawgn86]

Thank you. Where would they be located?

 

[ILENGINE]

Either on the front of the transmission or the front corners. different mowers and transmissions use different setups so need to look around the front and see if everything is attached.

Some will have both front coners, some just one. Some will have a connection on the front and others will be the front top.

 

[StarTech]

The RS800 anti-rotation bracket are on the front corners bolted to the frame with L brackets. On the transaxle the bolts a thru with the brackets on the top side of the mounting holes.

 

[dawgn86]

I checked everything I could get my hands on and it all seems tight. I will keep looking and see what I can find.
Thanks for all the tips.

 

[Forest#2]

So the motion dirve belt comes off:

Here is a link to download a owners manual.
If the link don't work do a on-line search and then download from sears parts direct. I did not look for a parts diagram. The belt routing diaqgram is on the bottom of the floor pan on yours.

https://c.searspartsdirect.com/doc/1502293L

Look at page 55.

The belt being stretched or wrong belt being to long or too wide will cause such plus if the idler pulleys are worn out.
Some of that version tractor have two rear pulley, some only one so don't get confused if it shows two rear ones and you only have one.

 

[dawgn86]

Thanks Forest,

I have the owners manual and the belt routing sticker under the tractor. The belt I ordered came from Sears Parts direct as well as the new pulleys. Mine does have the two rear pulleys which are about 3 months old.

 

[Forest#2]

Was the old belt also jumping off or did the problem surface AFTER you replaced the belt and pulleys?

 

[dawgn86]

My bad.... I got this drive belt from Lowes. I think the belt I took off was possibly the original, but the belt stayed on the few times I mowed with it before replacing.