[SuziBlu]

Love the extra power my electric fan gives over the old steel fan, what about an electric water pump ?

I have read up on them, can free up quite a bit of power, even when running at full as they are a far more efficient pump, meaning less power needed for the same LPM flow.

Anyone here have one, tried, ??

Im thinking about one, not sure yet.

[Gwagensteve]

done it, ran two Bosch pumps to replace the failed water pump in my 660cc motor.

I'm now still using one to boost flow to my rear mounted radiator, but one died when the motor took on water.

Yes, they work, as in they push water around the engine. They aren't anywhere near as reliable as the stock mechanical pump, just the same as thermos aren't as reliable as the stock mechanical fan.

If you think that they give you more horsepower, go for your life. Basic physics disagrees with you, but we've been down this track before. If the stock pump consumed 1HP maximum and you replace it with a pump with a 760 watt motor you've gone backwards because you now have to generate that 1HP in the alternator which is somewhat less than 100% efficient.

What in fact is the case is that these pumps don't flow as much water as the factory pump, just the same as thermos don't throw as much air as the stock fan. Do they flow enough? Maybe... maybe not. That's where your "increased horsepower" is coming from.


Steve.

[SuziBlu]

Steve, old design, pump compared to a modern design.

This is what I am led to believe, the pump itself is far better designed, so pumps either more water for the same power usage, or, less power for same water pumped.

If a big radiator is in new condition, and the engine has been chemically cleaned, ie, as close as possible perfect design heat transference, so only a very small amount of water is needed, the old stock pump is still trying to pump full flow where as the electronic controlled pump is only pumping the required flow, doesn't it stand to reason there is less power loss ?

My thermo very rarely comes on, only when in really dead slow speed, or, with a following wind, so I have a win there, surely.

[JrZook]

If the potential of gaining a few ponies outweighs reliability go for it. You got any figures for the power draw of the pump in question?

[SuziBlu]

Reliability is paramount, I believe in electronics. Many here poopoo thermos, mine work perfect, dont know of a modern car built with the old steel fan, even cluched fans are a rarity now.

Im not sure of what I need, one suitable for a 5l motor uses 7.5 amps max flow. With the controller and no thermostat, flow rate may be as low as 1 amp.

Thing I like about them, besides a few other things, turn your motor off, and the pump will keep running, cooling your engine down gently, thats got to be better hey.

The 5l may be overboard, there is one for 3 liter motors, but as they will only draw the power needed to pump the required water, not running at full flow constant, bigger may be better in my way of thinking.

[Paulw]

I also tried an elect water pump and experienced a slight noticeable improvement in performance(engine definitely felt more free revving) and a improvement in economy.
But what ever you do don't get the Davies Craig system.

Apart from the controller not working correctly- it would reset it self every 30sec when the supply voltage went above 13v(ie all the time when the car is running), the pump failed after about 6months of daily use. I had the larger model which seemed to flow too much for a M15a so the controller couldn't maintain correct temps( running cold).

[SuziBlu]

Do you still run one, or shyd away after the bad experience.

Was Davis Craig that I was looking at, no reason other than punch up google an they on top, hence the ask here.

[Paulw]

In truth I miss having it as anything which give a bit more punch and better economy is to me the gold standard for car performance mods, plus when I returned to using the mechanical pump is when I noticed the most difference.

I have tried running the controller with a diode(high current) from the 12v line to drop the incoming voltage by about 1.2v and it seemed to fix the resetting issue. To replace the pump I've been trying to find something which flows around 80ltr per min and have been looking at maybe a remote mount one by meziere-enterprises.

[droverdave]

Why dont you take the water pump belt off and take it around the block. I dont reckon youll notice any difference......

we put a davies craig or whatever it is system in a mates rx7. It worked but pretty complex com compared to a standard pump.

[SuziBlu]

My brother is a electrical technician, Ill get him onto it, running diodes, is sort of spanish with a french accent to me.

http://www.ebay.com.au/itm/MEZIERE-REMO ... 20d5d6430c

The above what you mean ?

Says nothing about a controller, I feel the controller to be the brains behind the system.

[royce]

Had one of the first Davies Craig systems on a mini 10 years ago, the difference was more than noticeable (mainly due to removing the engine fan I imagine)

What do you mean by resetting? there is no resetting function in them? they wont run continuously in a small engine, they sort of pulse the coolant around.

[Gwagensteve]

I have a Davies, Craig pump as a spare if my Bosch pump dies, but IMHO those Davies, Craig pumps are rubbish. They're a thermo fan motor and use a shaft seal. Based on their own data for service life, you could expect one to fail at about 140,000km on a normally driven car. That doesn't meet OEM specs, especially when a failure will kill your motor.

The Bosch pumps don't have a shaft seal - they are mag coupled. My failure with the bosch pump was due to water ingress to the motor - the ones I used were designed for inside the cabin use as a heater booster for VW products.

I still don't agree with your physics Suziblu. The exact same claim is made about thermo fans. As per usual, for all the claims to be made about them to be true, the factory must have no idea how to engineer anything. How come the OEM car manufacturer can't engineer anything yet some factory in china and a fancy printed box can miraculously make pumps that are 500% more efficient or thermo fans that put power back into your motor or something.

What in fact you are doing is sailing closer to the wind - cut back water pump flow as far as possible and hope you don't crack a head because there's some point that's not getting enough flow.... run a fan with half the output and hope because it's running flat out when it runs that it gets the job done.

Pull an electric water pump apart. They look surprisingly similar to a mechanical water pump.There's no magic in there. I'll give you 20%, maybe 30% efficiency on improved pump design. Funny though, your alternator is only 70% or 80% efficient, so just like the thermo debate, you're not actually gaining power on the long game.

The benefit with thermos and EWP's is that you can run them only when required. That's cool, so long as you know what you are doing. I'll tell you this much though, when you want the extra power, the EWP and thermos will be running.. so there goes your HP benefit... because were back to the alternator and its inefficiency again. Maybe you'll find an alternator that's 30% more efficient though, because shiny boxes and marketing hype can bend physics. K&N are proof of that.

OEM's now use thermos for a few reasons, none of them associated with how awesome thermos are. They run thermos for packaging with transverse motors (this wasn't always the case - toyota used hydraulically driven thermos for some years on FWD cars) They run thermos because they are light and cheap, they run thermos because they can be used to tune emissions. What you will notice though is that once you move into 4WD applications, the number of thermos fall away and the number of mechanical fans increases. That's just because the manufacturers don't know anything though and just like robbing us of power.

So once again, we're back to "you don't get anything for free"

I have no argument that not spinning the drag and inertia of an engine fan frees throttle response. I have no argument that when the thermos aren't required and you rev the car out, there's more power there at the wheels. I can also say at low speed/off idle when the thermos kick in it's all reversed and I have doughy throttle response and power loss. This was very evident with a manual, less so with the auto.

Steve.

[SuziBlu]

"I still don't agree with your physics Suziblu. The exact same claim is made about thermo fans. As per usual, for all the claims to be made about them to be true, the factory must have no idea how to engineer anything."

Do you use extractors, do you still have the pea shooter size exhaust system, do you non stock tyres, do you have a lift kit, why is the radiator in the back of your car, what shockies are you running, list is endless Steve.

Car makers, unless you are talking about upper end, build to a price, shave a few cents here and there, perfect.

Vane type pumps are so vastly superior than any other pump its not funny, all air and water pumps I know, except high pressure, are vane type, engine cooling water pumps are not in the slightest similar, like chalk and cheese.

I do agree, when everything is running hot, then there is no power gain, but, and I can only talk for myself here, I run a custom radiator, its about 3 times the size of the stock, front had to be cut to enable installation, sorry, but I do not think the stock is suitable, the engine was chemically cleaned before being installed, i use liquid to stop hydrophobia, and so, as far as I can make it, my engine is perfectly cooling, way manufactures specification. I run thermos, only time they come on, is in bog down gear, where power is somewhat less of an issue because in bog gear, there is more than enuf to spare, at higher speed, never thermos, more power, or less fuel used. Similar to electric water pumps I feel, at bog gear, so what if it comes on hard, im creating 100hp doing 10kph, I am very seldom there, im in the higher speed bracket, , a 5% increase in power to the wheels, is a huge upgrade in a 100hp engine.

[Paulw]

royce wrote:

What do you mean by resetting? there is no resetting function in them? they wont run continuously in a small engine, they sort of pulse the coolant around.

Not sure about the older ones but with the newer controllers when they are first turned on they do a self test where all the leds flash and the ewp/fan is pulsed(I assume so they can check for an overcurrent/open circuit condition) . I have two controllers (davies craig sent me a replacement and the new one had the same issue) both when the incoming supply voltage is above 13.25V would at exactly 30sec would reset ie. all the leds including the fault led flashing+pulsing the pump/fan. To rule out an issue with the jimny's circuit I check them out using a bench power supply and they still had the issue. I also used an amp meter to make sure the pump wasn't the culprit and it was drawing the correct amps.

The Davies Craig rep kept trying to tell me that it was possibly with the way I wired up the fan relay but the fault persisted even when the fan output was disconnected from the relay.
In the end when the pump shit it self i pissed it off.

I agree with Steve regarding the quality of the ewp I pulled mine apart and it is crap, although I followed all of the instructions regarding
installing the pump the shaft seal failed causing coolant into the motor after about 15,000k's.

[droverdave]

Gwagensteve wrote:

OEM's now use thermos for a few reasons, none of them associated with how awesome thermos are. They run thermos for packaging with transverse motors (this wasn't always the case - toyota used hydraulically driven thermos for some years on FWD cars) They run thermos because they are light and cheap, they run thermos because they can be used to tune emissions. What you will notice though is that once you move into 4WD applications, the number of thermos fall away and the number of mechanical fans increases. That's just because the manufacturers don't know anything though and just like robbing us of power.

I don't think that is a fair comparison as all/most 4wds have a north south engine layout where it makes sense to use a mechanical fan, so you would expect more of them to use it.

Late model bmws use electric water pumps it seems. I bet its a fairly complex control system to make it work well.

http://www.ebay.com.au/itm/11517586925- ... 417fda5fc2

[jdk81]

To me it seems like an expensive way to over complicate something, and reduce reliability.

By all means try it, but a mechanical pump and fan seems so simple.
Belt, wp bearing + seal (both of which last a real long time).
Viscous clutch fans are fancy enough for me, introducing another mode if failure
cheap, proven, effective and efficient

Electric wp
Motor and seals - unknown reliability
alt/battery are crucial
Wiring control system
There is efficiency loss in the power conversions
mech - elec - mech

More expenive, reliability unknown, more dependent on other systems.
For how vital it is, and what is at risk, it seems like a huge gamble with very little benefit.

If you are that desperate to give away money, fit a hiclone and be done with it.

Advertising: convincing a fool to part with their money.

If a g16b/g13b/g13bb isnt enough in a sierra, you are forgetting why you are driving a sierra.

[JrZook]

SuziBlu wrote:

Vane type pumps are so vastly superior than any other pump its not funny, all air and water pumps I know, except high pressure, are vane type, engine cooling water pumps are not in the slightest similar, like chalk and cheese.

Last time I looked at a generic mechanical water pump it looked like a rotary fixed vane type....

[sideways]

Instead of spending $11ty on an EWP setup that may or may not make a difference, why not spend the money on a nitrous oxide system?

G series crack heads and blocks often enough without messing with the cooling system.

[Gwagensteve]

Or lighter wheels or lighter seats or lighter tyres or less fuel in the tank or pull out the passenger seat or remove the bull bar or remove the heater box or scrape the bitumen sound deadening out of the interior or remove the inner guards or remove the windscreen frame or the doors or run a fibreglass bonnet or anything else to provide more performance through lower weight.

The idea that everything the factory fits can be improved upon is interesting, sure, cars are built down to a price, but so is nearly every aftermarket component. I'm not impressed with the quality of the Davies, Craig products I've seen, except their trans coolers which are made by PWR. I'm also rarely impressed with the quality of aftermarket replacement parts. I'm rarely disappointed with the quality of factory genuine parts which are "made down to a price" and yet, amazingly, were clearly engineered by people who had no clue.

I don't profess to know more than the factory Suziblu, so I'll happily admit my car is a bucket full of compromises and parts which are overworked and therefore don't offer anywhere near standard reliability. However, I have also fitted an engine which is mechanically standard that's adequate to do the job. It has extractors because the stock manifold was cracked, not because I thought they would give me 0.0005Kw more power. It has a rear mounted radiator because the stock location isn't appropriate for my use. It has a paper air filter, not some flyscreen that tells me I'm going to get 15% more power. It has heavily limit strapped suspension travel. In many areas, it's conservative, because conservatively engineered cars don't fall apart, break, and are therefore are more successful.

I had electric water pumps. They're flaky. I don't know how much power they added, I suspect none. I'm now glad I have a mechanical water pump. It's very reliable and if the electric booster pump fails the cooling system is still OK. You can search for someone to tell you how awesome they are, or you can believe the advertising nonsense. Don't, however, use the "because the factory now uses them" argument to boost your case, because the factory doesn't use them for added power, and in any case, everything the factory does is just made down to a price and can always be improved upon.

Your logic is as bendy as your physics.

Steve.

[SuziBlu]

Ok, thanks Steve.

[jdk81]

If you are itching to spend money, you could try a more efficient impeller to replace the pressed metal impeller.
then get wp pulley % smaller.

Change the wp pulley size based on increase in impeller efficiency.
Gain true power saving by % change in wp pulley size.
stock reliability, better performance, and more efficient.

[SuziBlu]

jdk81, sorry, im don here, seems im talking to er, well being answered by people who wish that they still walked, before the wheel was invented, its ok, ill speak to a rock, or maybe a brick, possibility is, better understanding that we live in the now, not as some understand, and that is 100 years or more ago, hey steve.

I ask a question, and am pounded down, attacked with great furry, lol, what fuckin ever, Steve, you should write a book on life the universe and everything, no questions asked.

Thanks all who answered with knowledge.

[fordem]

droverdave wrote:

I don't think that is a fair comparison as all/most 4wds have a north south engine layout where it makes sense to use a mechanical fan, so you would expect more of them to use it.

Ever looked at a JB or JT series Grand Vitara? North/South engine layout and dual electric fans. In comparison my SQ series GV (with the same J20A) uses a single viscous coupled fan.

My Pajero is also similar to the JB series - north/south engine & dual electric - and if we're going to discuss reliability - one of the Paj fans is dead - (brushes wore down & the springs destroyed the commutator)

[Rhinoman]

Manufacturers are moving towards electric water pumps because there are gains to be made by only running the pump as hard as it needs to be run. Usually they run them as a booster pump with a smaller water pump. Doing it that way means the electric pump isn't run continuously which helps reliability and the smaller mechanical pump takes less power to run, I don't think anyone has yet come up with an electric pump that has a long enough life for continuous use, I looked at the Davies Craig pump and I thought that the life was actually quite short.

[ChrisN]

How do W2A intercoolers move the water around? I thought they used an electric pump?

[Gwagensteve]

Yes. The one used by the TRD supercharged hilux was an excellent Bosch pump. They don't ususally run constantly though, generally only under boost. IIRC

Steve

[Rhinoman]

I think I shall have to run some tests on this, does the Davies Craig pump have diagnostics? I have designed a few OEM motor products and diagnostics are essential, I would certainly want early warning of a water pump failure.

[royce]

how would it tell you its about to fail?

[Rhinoman]

You can monitor the derived phase currents in software to check that the torque/rpm curve is as expected. On the hardware side the voltages across the drive transistors are monitored to check for short circuits and open loads - there are a few automotive qualified smart motor drivers available. The important thing is to know that the pump has failed before the coolant temp goes sky high. I'm intrigued by this now, I think I will try this, I'm already looking to add a smart fan and smart alternator.

[Paulw]

There is no over current protection apart from fuses as I found out when my pump failed and had to limp home trying to let the engine cool down and drive in short bursts.
It's so easy to use a sense resistor and a couple of comparators with a high and a low set points for under/over current protection but the controller will only fault on a open circuit.

The instruction manual for the Davies Craig ewp states that the input voltage range is 12-13.5V, most cars go above 13.5v when running I even checked the Jimny workshop manual and the hi range for the alternator output is 14.2-14.8V.