Electric water pump prices!

[cat007]

Was thinking it would be nice to get an electric water pump for the Supra so when I'm stopped after a blat around the track, I can have the pump and the fans going to keep it cool.

I thought it was a good idea - until I saw the prices of them! Over $500 for a pump! WTF

Seem's pretty ridiculous to me?

[Dell'Orto]

Make one then?

[cat007]

Make one then?

Could be an interesting project. Anyone here tried to make one?

[sergei]

Make one then?

Could be an interesting project. Anyone here tried to make one?

easiest to make is to use blower fan motor and couple that to random water pump

[cat007]

easiest to make is to use blower fan motor and couple that to random water pump

Oh yeah?

Or maybe even an electric motor to drive the existing water pump?

[sergei]

easiest to make is to use blower fan motor and couple that to random water pump

Oh yeah?

Or maybe even an electric motor to drive the existing water pump?

It has been done before.
I have seen a few V8 dragsters having this setup (a small V belt and random electric motor of appropriate size)

[cat007]

Would there need to be any sort of speed controller if I just used an electric motor to power the built in engines water pump?
Or could I just run the pump at full speed all the time?

[xsspeed]

Either, full speed all the time will put more constant load on alternator

[sergei]

Oh BTW, have you been here: http://www.daviescraig.com.au/Electric_Water_Pumps-list.aspx ?

[wde_bdy]

They are expensive because (in theory) they have to last a long time and one failing could result in a very angry customer wanting a new motor.

Callum

[cat007]

Yeah had a look on that daviescraig website.
So expensive!

I wonder if an electric fan motor would have enough grunt to drive the pump?

http://www.alibaba.com/product-gs/25572 ... ctric.html

[Dell'Orto]

I was more getting at the fact that you couldnt build one that would do the job and last for $500, but hey - if you can go nuts!

[cat007]

I was more getting at the fact that you couldnt build one that would do the job and last for $500, but hey - if you can go nuts!

Rightio. Point taken.

/end

[Malcolm]

FWIW the motors that Davies Craig use in their water pumps appear to be identical to those used in their radiator fans, so it stands to reason that you may be able to achieve something similar using a regular radiator fan motor. The problem would be the pump, I suspect that a regular automotive water pump may have a bit too much resistance to be easily turned by an electric motor - the Davies Craig ones seem to spin quite easily in comparison.

[Bling]

Just plumb a bilge pump inline

[Malcolm]

Also FYI, I wouldn't necessarily claim that the Davies Craig pumps "last". In the time I was in FSAE (4 years), we probably bought 6 or 7 of them, mostly due to the frequency that they would start leaking or burn out. They didn't see anything like the use that a road car would either.

[Dell'Orto]

No neither would I, have heard many stories of them failing. That said, stockcar guys use them and take a hell of a hiding.

[cat007]

No neither would I, have heard many stories of them failing. That said, stockcar guys use them and take a hell of a hiding.

They only use them for short stints though - and I wonder how many seasons/hours they actually get out of them

[Dell'Orto]

True, but they do get more vibration than the average road car too. They seem to get good life out of them, definitely more than a season.

[sergei]

Well, I looked at the power consumption of the Davies Craig pump and it is hovering at ~ 100W, which is quiet low.
If the Davies Craig pumps burns out, it means it was not designed for load and/or temperature range, which means the motor is not up to the task (ie they recycled motors from the fans).
If the Davies Craig pump leak, it means that the seals are too weak, probably because motors do not have enough power otherwise.

I think the pump needs beefier motor (preferably induction with VFD) and of construction similar to factory water pump (all metal, tight seals).