The V8 Owners Forum -

Hi , I have got a 3.9 serpentine type engine (with dizzy and intermediate cover) but want to swap the belt and pulleys for the older type SD1 V belt and pulleys ( space is an issue ) I believe that the serp type water pump runs in the opposite direction , is there a way around this problem? many thanks David.

As long as you get all of the ancillaries, pulleys, etc. etc, then the water pump will be turned in the correct direction.

I think your crankshaft maybe too long and need a spacer too.

Chris.

Are you planning to keep the intermediate cover and serpentive water pump ? I think that you can run the pump in opposite direction since the vanes are in certain angle to the rotation. It will physically run backwards but not pump that effective. Maybe someone has tried this, though ?

Thanks for the replies , yes I am keeping the intermediate cover with the distributor drive, I just wanted to get rid of the serpentine belts and pulleys and use the SD1 set up , but the water pump will run the wrong way , thanks David.

ChrisJC wrote: ↑Mon Oct 26, 2020 8:40 pm As long as you get all of the ancillaries, pulleys, etc. etc, then the water pump will be turned in the correct direction.

I think your crankshaft maybe too long and need a spacer too.

Chris.

The 'serp-belt' and 'V-belt' front covers use different water pumps - these pumps are centrifugal pumps and need to turn the correct way (as designed) to operate efficiently.
serp vs V-belt pump by Tom Cranmer, on Flickr

I would not just bolt the V-belt pulley onto the pump for the serp-belt

the most compact front cover is the later GEMS/Thor if you don't need a dizzy.

I remember reading somewhere a peep had overheating issues on a serp motor. The guy had done mods as you want to and indeed got the whole thing running .....completely overlooking that the water pump was now running backwards .....so , no , you cant run the pump backwards

Electric water pump?
http://www.super7thheaven.co.uk/rover-v ... ater-pump/

Ian

Ian Anderson wrote: ↑Mon Nov 02, 2020 9:17 pm Electric water pump?
http://www.super7thheaven.co.uk/rover-v ... ater-pump/

Ian

Or even an electric motor driving existing pump

I have seen somewhere an electric set up made by morroso, will have a look at one of these , David