Electric water pump relay

[J-440]

I have the Meziere 300 series electric water pump for a 440 and was wondering if I need some type of relay in the harness. The pump right now is hooked into the fuse block under the hood, which is tied into the fuse box in the car, which is tied into the ignition switch. So when the key is in the run position, naturally the pump will be running. Do I need a type of relay similar to the one that is in an electric fan setup? Thanks again.

[waynieZ]

Thats a good question I'd be interested in the answer too.

[cees67]

the fan only comes on at high temp setting and kicks off at the same temp setting on the way back down ....if the engine is running that water pump should be running as well. no relay. mine is wired to the ignition as well

[J-440]

Preciate it 67...ya'll have a good weekend.

[GregWeld]

A relay is nothing more than a "switchable switch"... it is a switch that can carry a heavy load - switched by a switch that is only capable of carrying a light load. This saves the light switch from burning out.

I would ABSOLUTELY run the electric pump on a relay... regardless of how it's wired now. All you have to do is to wire the "LOAD" (the pump) to the relay and have the relay doing the heavy current... and use the wiring you have now run to it - to switch the relay.

I would think that the pump should be run "continuous". So it might only be switched on once during the run cycle... but should still be on a relay. The wire gauge and relay should be sized correctly for the load. Looking at their website - they sell a 30 amp relay as an "upgrade"...

[J-440]

Greg, so just wire the relay using Meziere's harness between the pump and the fusebox/ignition switch? Would I still need to use the relay even though I'm using a 140 amp alternator as well as the stock voltage regulator? Thanks again.