EMP Stewart Water Pump

Muttleys V8 · Post by **Muttleys V8** » Thu Jan 31, 2008 9:27 am

I have just got shipped over from the States a EMP Stewart Water Pump.
It's a great peice of kit which can pump 56 gallons of water around the system. The reason for buying it is to try and keep the temp down while stuck in traffic!

It's not a varibale flow pump so it's either on or off!

The question is? can I leave the machanical pump in place and just use the electric pump as a booster, will the machanical pump restrict the flow of electric one or will I need to grind down the implellors (sorry about spelling) of the machanical pump?

The engine is a 5L Rover V8.

Many thanks
Steve

chodjinn · Post by **chodjinn** » Thu Jan 31, 2008 11:28 am

In short, yes you can run both the pumps at once.

There are a few people on here who don't favour the electric type water pumps and will quote pump volumes etc etc compared to the mechanical. However, since you are using it in conjunciotn with the original mechanical pump it can only aid in boosting water flow. They usually mount at the bottom of the radiator (that's where mine will be going).

However, I have a few good reports of just the electric pumps on their OWN are sufficient enough for the RV8 in many applications; although it does seem to be a bit random whether they work well, very well or just poor! I have removed my mechanical water pump in favour of a Davies Craig EWP Pump.

Muttleys V8 · Post by **Muttleys V8** » Thu Jan 31, 2008 11:38 am

The electric pump will be set to come on at around 86c when stuck in traffic, am just concerned that if the machanical pump is only doing 700rmp, will it cause a back-log of water behind it?

The Stewart pump has a pump life of 10000 hours compared to the 3500 hrs for the davis graig pump I was looking at, the adventage of the davis graig pump is that is can be varibale flow!

Steve

alex · Post by **alex** » Sun Feb 03, 2008 4:53 pm

Hi.
Ive got a stewart industries one in mine. aswell as the std pump. its mounted low down below the radiator level so its always got a good head of pressure feeding it.
Make sure the pipe clips are quality and tight.

dont ask how i know this.
alex.

stevieturbo · Post by **stevieturbo** » Sun Feb 03, 2008 5:41 pm

The Stewart stuff defo looks like nice gear....

Im sure you could also use a controller with it, as long as you can find one that will handly the currents involved. Id certainly buy it over the DC pump.

Muttleys V8 · Post by **Muttleys V8** » Sun Feb 03, 2008 6:45 pm

stevieturbo wrote:The Stewart stuff defo looks like nice gear....

Im sure you could also use a controller with it, as long as you can find one that will handly the currents involved. Id certainly buy it over the DC pump.

The tech guy from EMP says that they are not variable flow units, it takes 12v to start the pump.

Would be good if they could be variable flow, make life so much easier!
Steve

alex · Post by **alex** » Mon Feb 04, 2008 9:00 am

Dont think speed control is that important really but try to find a sensor to switch it with a small difference between off and on temps that way it will cycle but keep the temp close to what you want.

Muttleys V8 · Post by **Muttleys V8** » Mon Feb 04, 2008 9:18 am

Alex
Any ideas where I can find this kind of sensor?
many thanks
Steve

stevieturbo · Post by **stevieturbo** » Mon Feb 04, 2008 5:47 pm

Any thermostatic switch would do ( via a suitable relay of course )

eg....what controls your fan ?

Paul B · Post by **Paul B** » Thu Mar 20, 2008 10:54 pm

chodjinn wrote:In short, yes you can run both the pumps at once.

There are a few people on here who don't favour the electric type water pumps and will quote pump volumes etc etc compared to the mechanical. However, since you are using it in conjunciotn with the original mechanical pump it can only aid in boosting water flow. They usually mount at the bottom of the radiator (that's where mine will be going).

However, I have a few good reports of just the electric pumps on their OWN are sufficient enough for the RV8 in many applications; although it does seem to be a bit random whether they work well, very well or just poor! I have removed my mechanical water pump in favour of a Davies Craig EWP Pump.

I have a Davies Craig on my hot rod. I took the guts out of the stock pump and sliced the front off for rad clearance. It has done just over 5000 miles with no problems.

I had a bit of a dilema with the thermostat, as it ideally needs removing and an electronic controller wired in to control pump speed/engine temp, but I have just drilled four 6mm holes in mine to save the pump dead heading when the thermostat is closed. It takes ages to warm up the motor as it always has some flow through the rad.

I bought a remote thermostat housing, which would make the motor warm up quicker, but have never got round to fitting it yet.

Here's where mine is mounted. I used a short elbow to connect it straight to the rad lower outlet.

One thing I'll say for the DC company, when I e mailed to ask about a whistling noise the pump was making, they sent me a new pump!!!! I told them I bought it secondhand, had no warranty, but they still insisted on sending me the new one, all the way from Oz! Thumbs up for them I reckon. By the time it arrived the whistling had stopped, so the spare pump is still in the shed somewhere.

stevieturbo · Post by **stevieturbo** » Thu Mar 20, 2008 11:11 pm

When I ran my setup like the above....even with the controller, mine always ran very warm.
Even pump flat out, it struggled to keep temps good.

And with the WP pulley removed, and only 2 pulleys left similar to above, I always had issues with the alternator belt flipping itself over and destroying it anytime I revved the engine..
I can only figure the belts didnt like so much wrap around the alternator or something.

The DC was quickly removed. Still baffled as to why mine worked so badly, when others seem to have success.

Ian Anderson · Post by **Ian Anderson** » Fri Mar 21, 2008 8:50 am

Stevie

Fan belt turning over is a problem on a 2 pulley system as most???? belt manufacturers have what appears to be a radial sort of band through them

Take he new belt and press the 2 sides together - if it twists it will turn over on the pulleys

Try and get an oriinal VW Beetle belt (the length should be about right) and use it - they are designed for 2 pulleys only and ( ran the Formula V engine at 10000 through corners and never had it jump but lost numerous after market ones first!)

Another fun fact - if you are on the strip with a system like this slacken the VW belt so you can touch the 2 sides between the pulleys - it will slip like hell and mean you are not spooling the alternator each time to 7000 rpm - said to be worth an extra 10hp on starts

Ian

stevieturbo · Post by **stevieturbo** » Fri Mar 21, 2008 1:49 pm

Ian Anderson wrote: you are not spooling the alternator each time to 7000 rpm - said to be worth an extra 10hp on starts

Ian

I find stuff like that hard to believe. Although at launch, I'd say its no big deal. Perhaps alter in the track some power might be appreciated more.

But at the same time, Id rather my fuel pumps and ignition had a full alternator powered 14v, than a weedy battery power 12v or perhaps less with no alternator charging.

Ian Anderson · Post by **Ian Anderson** » Fri Mar 21, 2008 3:44 pm

Stevie

It will still give you 14 volts even although the belt is slipping. How many revs does your engine need to turn to get 14 volts - a little over idle I would guess - so it wil be on 14 volts.

Have a look at the engine bay of something like a Lola T70 they actually drive the alternator off the driveshaft!

It does make a difference.

Oh and on the V we also actually stripped out the electrics and ran it solely off the battery - 3 *12 lap races and practice on 1 charge - big sparks as we tended to run 6 volt coils and a resistor so they were running on about 9 volt - without the resistor we got 2 race meetings per coil!

Ian

stevieturbo · Post by **stevieturbo** » Fri Mar 21, 2008 4:17 pm

Never thought of it like that.... Suppose they dont need to spin fast.