Electric water pumps

[cusword]

Somewhere I saw a flow diagram that explained the problem with heaters not getting an decent flow and the solution of a second pump.

Where did I see it?

David

[rgh0]

You dont need a second pump - just locate the heater hose that goes to the original pump suction on the right of the front cover to the suction of the new electric pump.

cheers
Rohan

[cusword]

Sorry but I don't understand. Can you tell me more?

David

[paddy]

With the convenional pump, the heater circuit is in parallel with the radiator circuit - so the heater acts like a second radiator, and dissipates heat from the engine. The bottom heater hose attaches to the front cover on the inlet side of the pump.

When an electric pump is fitted, it goes inline in the bottom radiator hose. This now means that the heater's bottom hose is on the outlet side of the pump, so the pump will then tend to push water through the heater in the opposite direction - which by itself isn't a problem, except that the circuit through the heater is then in parallel with the engine, so a fraction of the flow bypasses the engine entirely.

The solution is to relocate the heater bottom hose - blank off the intake on the front cover, and attach the heater hose to a new tee on the inlet side of the new pump.

Paddy