Electric Water Pump

[richardm6994]

Sunday brought some hot temps (around 26C) and having a spontaneous drive out in the kit I got thinking about how good the electric water pump that I've fitted in the V8 installation really is.

 

During my drive, the cooling system had its first proper test.....duel carriageways, fast twisty roads.....and then to my horror about 50 minutes of 2mph TRAFFIC!! During this drive, my coolant temps maxed at 90C....which I think is pretty impressive given the V8 lump it's trying to keep cool.

 

Due to space restrictions, I ended up using a Davies Craig EWP115 with digital controller;

http://www.demon-tweeks.co.uk/performance/water-pumps/davies-craig-ewp115-alloy-water-pump-digital-controller-combo

 

I was nervous about how good it was going to be and couldn't find very many V8 related reviews (hence this post).

 

The way the pump and controller works is as follows;

You program your desired temp (for mine it's 85C).

 

When the coolant is below 75C, the EWP pulses on and off (about every 3 seconds or so) at about 33% speed. This allows for a really quick engine warm up and no need for a thermostat.

 

Once the coolant is over 75C, the pump increases from 33% speed to 100% speed as you get closer to your programmed temp.

 

If the coolant goes 3C over your programmed temp, then the controller switches on the electric fan (in my case a kenlowe fan that is also bl00dy brilliant).

 

 

For normal driving, there isn't any noticeable difference between the EWP and standard pump set-up (from past experiences).

I've not tried the car on a track day yet so I can't comment if the EWP is up to the challange, but my feeling from what I've seen so far is that it would easily manage.

 

The EWP really comes into its own when driving slow or stuck in traffic. Because the speed of the EWP is not linked to the engine's rpm....the EWP can be pumping at 100% even though the engine is just idling.

 

The only criticism I'd have on the system is that after the controller has switched the fan on, it has to get to about 5C(ish) below the set point (so in my case around 80-82ish) before the fan is switched off.

 

 

Installation is straight forward and it comes with a really good wiring loom that's plug and play.

 

For bleeding the cooling system, I connected 12v directly to the EWP (bypassed the controller) so that the pump was running at 100% whilst all the air was bled out (no need for engine to be running / hot water burns lol).

 

I would certainly recommend this system to anyone and although it's a bit pricey, if you're having overheating problems this summer (especially in traffic jams) then this could be a possible solution. They do 3 sizes, and 80, 115 and 150. The 115 keeps my 3.9v8 cool so there isn't much that can't be catered for in that range.

 

I have nothing to do with this company / product, just a happy customer review that I hope provides useful information to others.

 

 

[fry61]

Any idea on current draw, Richard? As when stuck in traffic with engine at tick-over cooling pump & fan may drag the battery done rather rapidly.

[richardm6994]

at full pump speed 10 amps....so combine that with the 18amps drawn from the kenlowe fan.....there's a lot to be said for a good alternator

 

That said, I've not had any trouble with draining the battery though (I've fitted one of these 60amp alts http://www.ebay.co.uk/itm/ALTERNATOR-LIGHT-WEIGHT-SMALL-RACE-TRACK-DAY-KIT-CAR-/281344425516?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item41816f3e2c#ht_2046wt_905).

 

The controller does has a visual warning signal when voltage drops too far (I've seen it a couple of times) but a few 'blips' on the noisy pedal livens the alternator up and sorts it out.

Edited June 3, 2014 by steamer

[edbond]

Did you remove your water pump / use shorter belt.

 

I have the T series engine on the superspec with the combined power steering pump and water pump and keep thinking of removing it and switching to elec pump but have no idea how easy it would be to find a shorter belt? Also keen on the pump continuing after a spirited drive and the engine off too.

 

Cheers

 

Ed

 

 

[richardm6994]

Hi ed,

Page 8 of my build thread shows the electric pump being fitted;

http://www.rhocar.org/index.php?showtopic=35307&hl=%20rv8%20%20into%20%20exmo&st=105

 

I removed the water pump and fitted a blanking plate with 2 inlets (1 inlet for each bank of cylinders).

Finding a belt on ebay wasn't a problem. Once everything was fitted I measured with a piece of string the belt length at both extremes of the tensioner....I then just looked for a belt somewhere in the middle of these two dims. Gates belts have their lengths in the part number so it makes for quick searching down the ebay results.

[brumster]

You've also forgotten another good aspect to these water pumps - they can be set to continue to pump even after engine off. This can be incredibly beneficial on some engine designs susceptible to heat soak and hot spots. Mind you, after a hot run, it's no hardship to leave the engine running for a bit to allow the heat to dissipate under a conventional pump - but these things can counter that. Just turn it off; no need to worry as the pump continues to run for a few minutes after engine-off to allow it to dissipate the heat.