after market electric water pumps

[Hybrid_From_Hell]

How do you fit then to say a v8

how much difference do they make

why ?

Pros and cons please !

Nige

[Bowie69]

Oi!

http://forums.lr4x4.com/index.php?showtopic=67483

[secondjeremy]

I suppose you could use 2 and get proper controlled cooling of each cylinder bank rather than a single pump attempting to feed 2 circuits at the same time which probably achieves equal cooling of both banks by good fortune.

There's also the possibility of circulating the water from the back which may help with the overheating problems some engines seem to suffer from at the back.

[Nobbymogs]

Nige Just buy one they are a great bit of kit but get the full kit with the controller as well helps stop hot spots as it circulates the water after turn off plus you can alter what temp the fan kicks in gets 11/10 in my book http://www.demon-tweeks.co.uk/motorcycle/water-pumps/davies-craig-ewp80-water-pump-controller-combo

[Team Idris]

Lets say you are working the engine really hard at lower revs, when the water pump is running slowly. Electric sorts that out

Electric maintains water flow between gear changes.

No thermostat bypass required, so the flow you pump is the flow you get.

At high rev the standard mechanical runs unnecessarily fast, so is parasitic load. (or even cavitating)

You are limited on mechanical pump size, but electric can easily be as big as you need.

Bads;

You're a fuse away from a blow up.

Pump shaft power may be twice the alternator shaft power, due to electrical losses.

[Team Idris]

Some interesting stuff on the other thread there. The faster the water flow the higher the Reynolds number, so less boundary layer and better water to metal heat transfer.

But also, watts = mass-flow-rate * heat-capacity-fluid * temp difference. If the watts are fixed and the mass flow rate doubled, the temp difference halves. So 100 over 90 deg.c becomes 100 over 95. (assuming engine makes 100 deg.c and rad exits 90 deg.c). 95 is further from the ambient cooling air than 90, so the rad works better. So you get a double helping from a faster water flow. But the back pressure is the square of the velocity, so twice the flow could take a lot more shaft power?

Sure is a tricky one

[Daan]

Some interesting stuff on the other thread there. The faster the water flow the higher the Reynolds number, so less boundary layer and better water to metal heat transfer.

But also, watts = mass-flow-rate * heat-capacity-fluid * temp difference. If the watts are fixed and the mass flow rate doubled, the temp difference halves. So 100 over 90 deg.c becomes 100 over 95. (assuming engine makes 100 deg.c and rad exits 90 deg.c). 95 is further from the ambient cooling air than 90, so the rad works better. So you get a double helping from a faster water flow. But the back pressure is the square of the velocity, so twice the flow could take a lot more shaft power?

Sure is a tricky one

from your post it only confirms my opinion that, other than being able to flow when the engine has stopped, I cannot see what the advantage is. I have only seen 1 application where there was an advantage: on a touring car, which had an alternator that would switch of the field on full throttle, so no power loss from the alternator. It did have a rather large lithium ion battery, which was fully charged at the start of a race, and flat at the finish. So any time you floored, it would drain the battery, but have about 1 hp more. In that case, ok there is a point, but on an off roader, leave it I reckon.

[FridgeFreezer]

Also worth looking at the rated lifespan of the EWP's, it was not a lot of hours last I looked. As team Idris points out, more flow does not mean better cooling.

Being able to circulate coolant after switch-off is a nice thing, but everyone's managed without so far... a few cars have had "helper" electric pumps and these can be had on eBay / breakers, but it's unclear if these are for engine helping or for helping heat the occupants up in winter.

I picked up an EWP at Sodbury for £40, carried as an emergency spare for Ladoga on the grounds it could be bodged to fit any engine of the fleet (from TDi to LS1) as a get-out-of-dodge measure.

[zim]

Nige,

I honestly think you have a problem with your radiator / fan setup. Yes you have a 5.2 but i've (touch wood), never had any issues - bearing in mind we regularly sit with it revving away for a while driving winches etc.

Boothy has run an ewp for ages, i have always run normal pumps and been perfect. My radiator is rear mounted and relies solely on its fans (with cowling) for cooling.

G

[FridgeFreezer]

A cheap experiment might be to turn a smaller pulley for the water pump, that will gear it up a bit so it's flowing more.

The 5.2 is kinda irrelevant, assuming the BSFC is similar or better than standard it's only making more heat than a standard lump when it's making more power, which is only when the skinny pedal is hard down. The rest of the time it should be fine.

[Team Idris]

" As team Idris points out, more flow does not mean better cooling." The other way about. More better'er.

Machining the cooling fan pulley down on air cooled Deutze works, but on water it may send the water pump into cavitation at high revs? I'm not saying it will, but it might. But as a short term mid-range rev test, it sounds a flippin' excellent idea

Thing is though, Alan Burns had poor cooling due to too big a rad. Andy Alisport fitted a thinner rad, re-fitted the thermostat and all was well. Alan used to rev it really high though, like cruel rpm. He made that landy shift right enough! It's interesting in that case, that more wasn't better

[FridgeFreezer]

Running the pump too fast may well produce cavitation, most V8 timing covers have cavitation damage on them although I believe the later (serp/P38) type are better for it.

I bet Alan did not have poor cooling because of too big a rad, more a problem of the installation or not having a stat fitted. Having a huge rad would be no problem if everything else was working fine. But, as two things were changed (new rad, refit thermostat) you can't say what was actually causing the problem.

[Team Idris]

True. Biggest we've fitted to a rover V8 was 100mm deep

One thing that does interest me, is that the core has the most resistance and the pump is directly after it. From a cav point of view, I think any pump should be just before the rad?

[Boothy]

EWP115, rear mounted 19"x31"x2.5" cross flow alloy radiator with 2x1" cores, supplied by Summit racing from the USA $165 bargain.

The pump is mounted at the rear of the vehicle and is fed out of the bottom hose and then pumps to the bottom of the engine, the flow is terrific.

Its a Serp front end with blades cut from pump, piped to the rear via 2.5" hydraulic pipes (bomb proof and semi- flexible) running more or less along chassis rails.

1x16" Pacet pro-fan (highest CFM of ALL fans) fed via temp switch, plus one manually controlled 12" Spal fan, which was fitted as a back up if required.

The EWP does not have the controller (even though I have it brand new in packaging) and is switched and alarmed to run continuously

Works an absolute treat, like Steve says doddle to bleed up, if you are worried about failure then put a temp sender in with a light or buzzer to prevent overheating in the event of a failure.

Cost new from Demon Tweeks £173.

As a plus side mine is usually nice and cool under the bonnet because most of the heat has been shot to rear of the vehicle, looks like jet taking off in winter when it warm.

You cannot have all this power without a uprated cooling system, the very laws of physics tells us that more fuel burned equals more heat, get your money spent you tight git, or stick an N/A diesel cool runner in and stop moaning.....

[FridgeFreezer]

And on the other hand - 4.6 V8, smaller than standard rad in the front, with fat cores and far too few fins, standard water pump, pair of old Audi fans... works fine!

[Hybrid_From_Hell]

Er

actually regarded as runnibg too hot

hence probs ...donr for emissions

N

[Hybrid_From_Hell]

Er

actually regarded as runnibg too hot

hence probs ...done for emissions

N

[FridgeFreezer]

actually regarded as runnibg too hot

hence probs ...done for emissions

Nige - what are you replying to there?

[Bowie69]

Nige - what are you replying to there?

Perhaps early on the chiraz?

[Hybrid_From_Hell]

ha ha hadeha

No, the Merlot

Am thinking of a additional pump unit vs a full replacment.

Need to sort out a couple of minor leaks n weeps and then give it some stick, see just how hot it gets off raod, if it does then plan is maybe to pop one in the rear tub, and plumb in / out

as an "Assister" unit, so keeping the engine Waterpump, and adding it in as an additional unit, poss triggered to switch on when fans do. Also there would by the nature of adding it

give additional water capacity....this way don't need the control gubbins, and aslo if assister pump fails, its not an issue ....

We will see.

[Jon White]

Cough......200tdi.......fan belt snapped about 5 miles north of Basingstoke.........drove all the way home with no water pump, and it still didn't overheat.........

You could have had a 200tdi machined from scratch from unobtamium the length of time you've been pissing about with that v8!

:-p

Jon

[SORNagain]

I guess the fan turned into a windmill and kept your engine cool!

I think some measurements would do wonders to reduce the speculation....thermocouple meters with two inputs are not expensive. You can then measure the temperature difference across the engine (or the radiator) while you are driving.

If you found that the coolant was entering the engine at 60 and coming out at 90 you would probably say the flow wasn't enough. If it was going in at 85 and emerging at 90 then the EWP issue would probably vanish!

[FridgeFreezer]

Deja-vu all over again Nige http://forums.lr4x4.com/index.php?showtopic=67483

Need to sort out a couple of minor leaks n weeps and then give it some stick, see just how hot it gets off raod, if it does then plan is maybe to pop one in the rear tub, and plumb in / out
as an "Assister" unit, so keeping the engine Waterpump, and adding it in as an additional unit, poss triggered to switch on when fans do. Also there would by the nature of adding it
give additional water capacity....this way don't need the control gubbins, and aslo if assister pump fails, its not an issue ....

You what eh?
This sounds like a rather over-complicated way of not actually proving what the problem is...

I think some measurements would do wonders to reduce the speculation....thermocouple meters with two inputs are not expensive. You can then measure the temperature difference across the engine (or the radiator) while you are driving.

^^^ This - for the amount of time, effort, and dosh you're potentially throwing at this on a hunch you could justify splashing out on a couple of extra temperature gauges semi-permanently mounted on the dash (you wouldn't struggle to re-sell a VDO temp gauge for good money) or even do something radical like wire an extra coolant temp sensor into the megasquirt and datalog it alongside all the other engine parameters, that would cost you a temperature sensor (£10?) and a small mod to the ECU, and would enable you to get a much better handle on what's really happening.

As SORNagain says, temperature sensors / loggers are peanuts all over eBay, you could plaster the thing in them for not very much.

[FridgeFreezer]

Under £20 for a digital temp monitor that could be used for programmable fan control (or even EWP control):

http://www.ebay.co.uk/itm/12V-Mini-Digital-Temperature-Controller-Thermostat-16D-/261097943971?pt=LH_DefaultDomain_0&hash=item3ccaa673a3

[Jon White]

I guess the fan turned into a windmill and kept your engine

Er.....what fan?