2400 water pump belt

[doublegarage]

My 2400 engine's water pump drive belt is in poor condition and I need to replace it.

Every manual I have read seems to suggest that the alternator and water pump are driven with the same belt, but my engine has one belt for the alternator and a separate one for the water pump. Since Superformance sells the waterpump belt (and I bought one) I assume I can't be alone.

But I don't understand how this works - I guess I have to remove the pulley from the front of the pump and swap the belt that way? But, how does the belt get tensioned?

Thanks,

-Richard

[DOMCHA31]

Hi Richard,

Here is the pic of the water pump and his belt



You have to remove the front pump pulley with the 6 screws and the setting is done through différent thinkness shims

Hope this help

Dominique

[doublegarage]

Hi Dominique,

Thanks, yes that does help. I have that manual, but now you've mentioned the shims I see that the part number 4174524 "anello registro" - translated to "ring" has quantity 5 in the parts list - so I guess you remove them to increase the diameter of the pulley and tighten the belt.

Got it - thanks!!

-Richard

[doublegarage]

To follow up - my belt was very loose, I removed it (first have to remove the the alternator belt to be able to remove the water pump belt_) and found that I had a 10x630mm belt.

researching the Fiat part number (4174521) this belt should be a 10x625mm belt. The belt I had bought from Superformance translates to a 10x615mm belt which is too short and rides at the bottom of the belt groove, touching the shims.

So I decided to improve the tension of my 630mm belt. I removed 2 shims and found the 630mm belt to be too tight - added 1 shim back and it seems to be pretty good now.

In other words, the water-pump pulley's shimming method seems to work very well at adjusting the belt, even when the incorrect size (too large) is present.

Thanks, Richard