Pump clutch ?

I have got a jabsco deck wash pump to be run on a belt off the engine, i have been told of electric clutches but cant find any info, have also been told i can run the engine with the belt loose and when i want to use the pump i tighten the belt with a tensioner on a cam, surely this would harm the belt. anybody got any ideas on how to fit some sort of clutch to the pump.
I dont think a centrifugal clutch (say off a go cart) would be suitable as the engine is low reving and would want to use the pump at just above tickover.

 

Its not common for cars in Uk to have airconditioning but some do. If yours has lift the bonnet and look at the front of the AC compressor,---that is an electric clutch 12v.

There a many shapes and sizes but you may find that one will fit your pump.

I would have thought that the Jabso dealer would know the model of the clutch required.

I have seen those pumps with a manual dog clutch.

 

If you Google electric clutch pulley you should find a supplier in the UK.

Here is a link for the US:
http://www.zacm.com/brand/eleclutches.htm

 

thanks for that, let the search begin.