ST-324 auger chain routing

[Will D 0]

Picked up a snow thrower for my 653, an ST-324. Anyone have a service manual? Only thing I can find is the assembly and operator's manual/parts list.

 

Someone removed the idler and tried just looping the chain around the drive and auger sprockets, which wouldn't work because the chain will hit the guards and the auger will spin backwards. I assume it goes like my sketch? A= auger sprocket.

[Sparky-(Admin) 26,272]

 

 

 

[WHX?? 57,982]

 

You may be right in your drawing but others will be along to welcome and hopefully have a pic or two. 

That manual does not show the chain routing, size or the size of the idler. You will need that and an idea of the chain length would be helpful as well. 

The idler bolt may be fitted in a oval hole for chain tension adjustment. 

[ri702bill 12,942]

Will - Welcome!

I too have the same 1964 32" snowthrower that I use on my 854 8 speed. Even though mine was 50 years old, it was NOS & never used!

Before I used it, I did a couple of upgrades that the 1965 & later models have from the factory. The big one deals with a re-routing of the drive chain and the addition of a second idler that is fixed mounted above the lower adjustable one. The early routing as you pictured it only puts THREE teeth of the auger sprocket in engagement with the chain - a recipe for stripped sprocket teeth due to insufficient chain wrap. The revised routing gives both correct rotation and much more engagement. Position the upper idler so that the chains do not touch...

The early lift flag had no provision for an assist spring  - I welded the tab and added those pieces. (Lowell sells the new style too).

The OE chain is #41 - the fixed idler I used was #40 - same pitch chain, a bit wider. Get a 10 foot length (#40 or 41) with a Master Link. You will need to cut it to the proper length. You also need to alter the OE front chain guard. I've used this for 6 seasons - no issues.

 

Edited 19 minutes ago by ri702bill