I’ve fitting an electric water pump to my Rover V8. The P38 water pump I was using tried to occupy the same space as the front 4×4 prop shaft. I had a mate cut and weld it, but clearance was still incredible tight.
Modified Rover V8 P38 Water Pump
This is the standard water pump.
This is what my cut ‘n’ shut pump looks like with the outlet moved about an inch higher.
I was always concerned the TIG welding had degraded the bearing. It seemed perfectly fine but who knows how long it would last.
With my mock-up propshaft in place you can see that there was still only 5mm clearance. Rev the engine a little and no doubt it could touch. Therefore going electric was probably a smart move.
I went for their vibration absorbing bracket, but I so far I haven’t been too impressed as the pump has already popped out twice. I’ll look at using the rubber but throwing the metal bracket in the bin.
Using some 10mm thick 6061 Aluminium plate I made a water pump blanking plate. Added to which I attached a 105° Chevy swivel water neck. I tapped the plate, thread locked the bolts and sealed the plate to the water neck with high temperature sealant.
With the plate in place there still isn’t a great deal of room but at least I now have a good 15-20mm of clearance to all moving parts. I did want to put the pump in the bottom hose; pumping water from the radiator; but the front differential, propshaft, oil cooler and remote oil filter were in crammed in the way. My engine bay compared to a Super 7 with a Kent engine is ridiculously tight.
The only room was in the top hose feeding the radiator. In this configuration the front propshaft now has a good 30mm of clearance. The 7 rib fan belt (7PK1260) now only drives the alternator and is over 1.1metres shorter than the standard one.
Davies Craig make several digital water pump controllers. These not just control at what temperature the pump kicks in, but they also extend the life of the pump. However, I’m using the electric fan output from my Megasquirt, a few relays, 2 temperature senders and 2 electric fans. If I have issues with this set-up, I’ll add a little home-made circuit to my ECU, that will switch on the pump at 80°C. I’ll also add a timer that keeps it running for a minute or so after the engine is turned off. I have a little Audi auxiliary electric water that I’ll add into the heater circuit to make sure I get hot air to defrost the screen.
Electric Water Pump Advantages
Mechanical water pumps are always pumping water when the engine is running. On start-up it’s pumping lots of coolant when the engine isn’t hot enough to actually need it. That’s wasted energy. In stationary traffic on a hot day, or after a hard run, the engine needs more cooling than it gets. An electric water pump delivers coolant when needed, more in tune with your engine’s specific cooling needs. This not just reduces engine wear and increasing efficiency. The pump creates less mechanical drag on the engine releasing even more power. PWM, can control the pump’s speed to precisely deliver exact volumes of coolant depending upon engine temperature.
EWP 150 Specification
According to various forums the EWP130 was more than plenty for a Rover V8, but seeing as my radiator is a fraction on the small side, I’ve gone for the biggest I could get. I don’t want slipped liners!
|Voltage||12 Volt Pump|
|Operating voltage||3V DC to 15V DC|
|Maximum current||10A @ 13V|
|Flow rate (max)||150 L/min (39.63 US gal/min) @ 13V DC|
|Operating temp.||-40° to 130°C (-40° to 266°F)|
|Pump design||Clockwise centrifugal with volute chamber|
|Pump weight||1,170 grams (2.6 lb)|
|Pump material||Aluminium (Powder Coated)|
|Burst pressure||500 kPa (72.5 psi)|
|Seal||Ceramic face seal|
|Fits hose sizes||35mm to 51mm (1⅜” to 2”) Inlet & Outlet -16AN (12)|
|Push-On fitting Size||EWP Inlet & Outlet 38mm