Electric Water Pumps.

[crf450 0 1 Cars]

Just wondered if anyone's had any experiences using these.I'm planning on fitting one to my new motor after looking in to the possibility's of fitting a larger pulley to slow my origonal pump down, only to find theres not really enough room.

My engine bloke recons when you start revving over 8k with an origonal pump running the standard ratio will start cavitating causing it not to pump right.

He also recons I will save up to 12bhp buy loosing the original pump .

I know the electric pump will load the alternator more, but as I may run electric power steering as well, I'm thinking of fitting a switch to the throttle so the alternator disconnects when I hit full throttle.

Cheers Martin

[Miles 331 1 Cars]

I will be fitting asn Electric one on mine soon or when I get around to doing the engine , I have thought about the cavatation as well considering mine will run to around 9k, I've spoken to a couple of people with them and it really does control the water temp by all accounts, If you need one let me know as I can get them dirt cheap.

[jonah 1]

Someone else was asking about these recently, here's the thread:

 

http://forum.205gtidrivers.com/forum/index...showtopic=16324

 

As I pointed out the electrical load is minimal so you shouldn't need to worry about disconnecting the alternator at full throttle.

 

If you're only worried about cavitation at high speeds, I wonder if it would be possible to modify the existing pump by fitting a modified high-rpm impellor? I've never heard of it being done but I imagine it ought to be possible.

[Guest Wiggs]

Strange this topic should come up... I was just thinking about this earlier, on a Turbo Technics 205, the turbo is water cooled and the only way it'll be cooled down after a good run would be to leave the engine running, the kind of thing a turbo timer would do.

 

Anyway, instead of that, I was thinking of plumbing in an electric water pump on some kind of timer or thermostat, like the fan, to continue pumping when the ignition is off.

 

I was also thinking about the fan on the car, when it stays on to cool things down, it isn't doing an especially great job is it? I mean realistically it's only cooling the water in the radiator, what about all that hot water sat in the engine?

[Anthony 1,003]

Strange this topic should come up... I was just thinking about this earlier, on a Turbo Technics 205, the turbo is water cooled and the only way it'll be cooled down after a good run would be to leave the engine running, the kind of thing a turbo timer would do.

You're overlooking something though Wiggs - when you leave the engine running after a hard run on a turbo car, you're doing it to circulate oil around the bearings rather than to water-cool the turbo unit itself.

 

If you switch the engine off with the turbo still hot, you'll get coked up bearings inside the turbo as the oil is no longer circulating and will get "burnt" onto the hot bearings.

[cybernck 403 1 Cars]

Anyway, instead of that, I was thinking of plumbing in an electric water pump on some kind of timer or thermostat, like the fan, to continue pumping when the ignition is off.

 

my T16 has got this fitted as standard .

 

 

but as anthony said, oil circulation is the main thing so try to drive the last few miles

(before shutting down) easily and then leave the engine idling for about 2-5 minutes

when you've stopped and it will be ok.

[Guest Batfink]

So would you still use an mi16 cambelt or would u need a smaller one??

[Deadliest Pug 0]

I spoke to our top engineer at work about this and he said don't fit one.

 

This is all on my V8 which Perkins did a lot of work on when they tried to make it a diesel.

 

Although the water pump is cavitating it still has a good amount of flow, on an electric pump it only measures the inlet and outlet temp of the water. This does not take into account hotspots. Because you run them without the Stat the water temp as an average might be spot on, but the reduced water flow means that you would get hot spots round say the top of the cylinder which is higher than normal. So despite it gaining around 6hp (It's the figure some V8 tuners have given me on average) I definitely wont be fitting one.

 

My engineer said water temp is easy to do, just get a more efficient rad, but water flow is the decider on how well your engine is cooled, it's the average temp across the whole engine, not just inlet and outlet difference.

 

Dave!

[Guest eccentric_uncle_rich]

I haven't seen an electric water pump fitted to a Pug but a lot of the Caterham and Westfield boys use them (I've got one fitted to my Westfield).

 

The most popular pump is the Davis Craig item (2004 Demon Tweeks catalogue page 197). The general concensus of opinion amongst the kitcar boys is to run them without the electronic controller but with the original thermostat fitted. We drill an additional two or three holes in the outer edge of the thermostat to maintain a small amount of water flow through the engine when the thermostat is shut (to prevent localised hot-spots in the cylinder head when the engine is warming up).

 

These pumps are extremely reliable when run flat out and you save £80 by not buying the electronic controller. You can also keep the water flowing through the engine for a few minutes after you shut the motor down which is a bonus. Prodrive also used these pumps on the Ferrari 550's they ran at Le Mans this year.

 

Richard.

[C_W 3 1 Cars]

Them electric water pumps must be proper bo!

[NickR 10]

One thing I never understood.

 

Load the engine up and / or rev it, this is when its going to need the water the most. I dont see how the electric pump could/would improve things. I on part load/low revs, wont matter that the permanent pump is sapping a little power.

 

Same thing with those altern-powers, when engines revving, sparking away more, needs the alternator for contious usage. I know as I had an alternator fail on me and within 200 miles on the motorway my battery went flat (and it is a good bosch 5 year battery).

[Guest eccentric_uncle_rich]

Them electric water pumps must be proper bo!

Well yes and no! Unless you're getting really serious about your engine modifications you're probably better off keeping the standard water pump.

 

If it works why piss about with it, saving a few horse power at 6000 rpm isn't going to make a noticeable difference.

 

The kitcar lads use them because it makes the engine installation easier.

 

Richard.

[red 0]

I'd agree as they have a life span of 2000 hours according to the info, I thought they were aimed at championships with restrictions on engine mods where this would possibly be quite a good gain, or fully blown race engines.

 

Regards Russ...

[Guest Wiggs]

You're overlooking something though Wiggs - when you leave the engine running after a hard run on a turbo car, you're doing it to circulate oil around the bearings rather than to water-cool the turbo unit itself.

Doh!

 

Yes, I was having an 'off' day. I totally forgot about that. So really I'd need to have an alternative oil pump too. Just as easy to get a turbo timer or leave the engine running a few minutes then.

 

Thanks!

[C_W 3 1 Cars]

One thing I never understood.

 

Load the engine up and / or rev it, this is when its going to need the water the most. I dont see how the electric pump could/would improve things. I on part load/low revs, wont matter that the permanent pump is sapping a little power.

 

Same thing with those altern-powers, when engines revving, sparking away more, needs the alternator for contious usage. I know as I had an alternator fail on me and within 200 miles on the motorway my battery went flat (and it is a good bosch 5 year battery).

Isn't it because the water pump is like an impellor spinning in water which means a lot of drag? espeically the faster the engine spins.

 

The alterpower thing is probably less useful for increasing power as you say.

[pug_ham 245 3 Cars]

One thing I never understood.

 

Load the engine up and / or rev it, this is when its going to need the water the most. I dont see how the electric pump could/would improve things. I on part load/low revs, wont matter that the permanent pump is sapping a little power.

 

Same thing with those altern-powers, when engines revving, sparking away more, needs the alternator for contious usage. I know as I had an alternator fail on me and within 200 miles on the motorway my battery went flat (and it is a good bosch 5 year battery).

If there is any benefit to be made from running an electric pump IMO it'll be that you can have it running at prime rpm (just below cavitation) to give best cooling efficency all the time whatever rpm the engine is spinning at but surely the radiator efficency is the most important.

 

Google search results for Alterpower , read some of the results & decide if it makes any worthwhile difference. If it did they would fit a similar idea to the BTCC or WRC cars surely? (don't know if they do though)

 

Graham.

[Guest Pugmasterful]

Sorry to butt in on this one but:

 

Another thing to bear in mind is that the water can be whizzing around the engine TOO fast. Therefore not actually getting hot at all, which is it's purpose. When I used to go grasstracking some mates of mine experimented with leccy pumps on their specials and sometimes made the situation worse.

 

There's probably some highly complicated formula to work it out, but I wouldn't know!