Drive pulley size

[Big Jake 18]

I got a1977 C120 I pick up to build a puller. I got it with no motor. I got a K341 16hp I need to know the drive pulley Dia. I need And if not to much to ask the belt size Thanks Jake :dunno:

[TT-(Moderator) 1,145]

OEM pulley sizes are 4" OD for the 8 speed models and 5.250" for the hydros. Both used a 5/8" wide belt.

Stock belt length for the 8 speed is 81.95" (OEM belt #7473) and the hydro is 84.22" (OEM #7478)

A puller might benefit from a different size - or even adjustable - engine pulley to vary the ratio. It's up to you to verify the "legality" within your pulling club / association.

[Big Jake 18]

Thanks TT for yor help Jake :dunno:

[Kelly 1,029]

Just a side note, if you use a aftermarket pulley be sure to use a iron pulley not a stamped steel one.

[carlsbarn2 7]

What speed difference could I expect by going to larger front pulley?I have 310-8 and C-175 8 speed.

[jonsteffen 6]

u talk about these ajustable pulleys i don't think i have seen one or if i have i don't rember what it looks like

[TT-(Moderator) 1,145]

LINK to an example of an adjustable pulley.

[Stigian 1,234]

OEM pulley sizes are 4" OD for the 8 speed models and 5.250" for the hydros. Both used a 5/8" wide belt.

Stock belt length for the 8 speed is 81.95" (OEM belt #7473) and the hydro is 84.22" (OEM #7478)

A puller might benefit from a different size - or even adjustable - engine pulley to vary the ratio. It's up to you to verify the "legality" within your pulling club / association.

Glad I found this thread, I was all set to machine a 4" pulley for my 6X6 project, I didn't know a hydro engine pulley was bigger!!

So thanks Terry post posting the above info and thanks to Jake for posting this thread in the first place :thumbs: