[Vwdiesel] More on coolant flow through radiator

Roger Brown r.c.brown at ieee.org
Sun Sep 5 19:46:34 EDT 2004

Erik Lane wrote:
> it seems that all the 1.6L diesel water pumps are the
> same, at least from the backside. i know that there
> are two different size hubs on them, but the pulleys
> themselves seem to be the same size.

If you have a 1.9 engine, the crankshaft pulley is larger than on the 1.6 engines, as is the water pump pulley.  However, if you
swap in a smaller 1.6 w/p pulley, you get an overdrive affect on the pump, larger crank pulley drives the w/p at a ratio grater
than 1:1.  I found this made about a 1/2 mark difference on the temp gauge running down the highway.  The trick is finding a 1.6
pulley that matches the 1.9 offsets.  I used a cast iron pulley that was close to the right offset, then fine-tuned it by
shaving off some of the inside flange surface on a lathe.


More information about the Vwdiesel mailing list