Morning guys,

What is the difference between a viscous and non-viscous water pump supplied for the Pinto engine?

Provision for fan drive viscous coupling via threaded boss on the drive flange.

The Viscous pump may need a larger bore for the pulley than the non viscous due to the thread being larger than the non viscous boss?

The pump isn't viscous is it ? It's the fan on the front and if you are using it on a kit you'll throw that and fit an electric one. The fan nut is left hand thread from what I remember but new pumps are cheap. The Transit used a fixed fan and Sierra were viscous.

cheers guys