QuestionI have a Sears Rider Model # 917.270851; 20.5 HP Briggs; 42” Deck; 6 Speed Transaxle Manual.
The problem I have is with the drive belt. It has become loose, to the point that it jerks while under a load going up a hill while mowing.
I have replaced the belt and the problem remains. The belt is routed correctly as shown on the bottom of the rider and as shown in the owner’s manual. The stock belt is exactly 94” outside diameter and it is a V belt measuring ½” wide and 5/16” tall. I got a 92” and then a 93” belt from Grainger to see if that would help, but it was impossible to get either belt mounted properly – too tight.
I have checked the drive pulley on the bottom of the engine shaft, and it looks ok. I have visually examined the idler pulley and the clutch return tension spring which both appear to be operating OK.
There is, however a lot of play in the clutch – so much so that the clutch almost has to be let all the way out before the belt engages. It was not that way when it was new.
I know there must not be a lot of belt tolerance because I just could not get the 93” belt mounted – only one inch shorter than the stock belt of 94”.
I am at my wits end to know what the problem is.
Is it possible that the Transaxle drive pulley has separated slightly causing the loose belt condition? That is the one thing I have not checked out because of the work involved in removing the transaxle assembly.
Help!!
AnswerIt does sound like you have a problem in the transaxle itself. Perhaps a few broken teeth on one of the cluster gears. What will happen is when the drive gear hits this section of the gear missing teeth it "jumps" as you indicate.
Before you look that far however make sure the that key didn't fall out of your axle (can only happen if you removed the tire)
