Electric water pumps

[mikethemechanic]

Magazine October includes article on mod to air inlet to help with electric pump - over many years and considerable involvement with Stags I have only twice experienced overheating with the standard well maintained water pump /radiator system, the first was when towing a caravan with an auto Stag and the second returning from Silverstone when the fan torque unit semi - collapsed so I have never seen the need to use an electric system and to then add rad shutters seems even less desirable.
The original system with good radiator and a high mounted overflow bottle WORKS so why go to all the trouble off electric, additional help can be given to standard system by use off low level indicator in overflow bottle, front spoiler to aid air ingress and rework of bonnet seal to allow air exit in heater inlet area.
Going further a case can be made for electric radiator fan and temperature sensor with timer relay to bring it on at correct times - the only use for an electric pump is if a small unit introduced to bottom hose area is wired in such a way as to assist circulation under extreme need but not as a replacement for a standard working pump.
don't forget many B.M.W.s, ford Granada's etc.used high mounted pumps without problems until loss of water for many reasons created the overheating.
Mike the Mechanic

[maynard flint]

As the author of the article referred to. The reason I have an EWP fitted is that the well respected Stag specialist who re-built my engine, will not undertake such work without fitting an EWP. This being due to inferior re-manufactured pump parts.
The result of the way the Davies Craig system is programmed, is a slower engine warm up period. Hence the radiator shutter to reduct this period.

[flying farmer]

I have had two drive gear failures on original pumps.

First one was on a Dolomite Sprint which I caught before it failed totally due to it chattering at idle. Couldn't be bothered to remove the engine to replace the jackshaft and pump so that was my first EWP conversion.
Second failure was on my first Stag, that seized the jackshaft, snapped the timing chain and lead to a full engine rebuild. That one ended up with a belt drive conversion, the first batch that Steve Hill produced.

Original pumps are great when they are working but a PITA to work on, and can lead to catastrophic damage when they fail.

I am not a great lover of the electric pump controller due to the slow warm up and useless heater output compared to the original set up. I prefer to drop the running voltage to 8V using a resistor and leave the pump running continuously. Can boost the voltage via a switch for extreme heat or track days (this is on engines producing over 250bhp and I am only using the EWP80)

I currently have 2 Stag engines and a Rover V8 with electric pumps, and the other Stag with the belt drive conversion.

Neil

[AndyM2]

The currently available seals for the original water pumps are poor quality and a poor fit so effectively an overwhelming case for an alternative.

The location of the original pump is an example of poor design in that it is located too high and leaves things vulnerable to low water levels.

As it stands the only option is the electric pump as the alternative mechanical pump isn't an option since Stagdad stopped selling his conversion. I think that used the Essex water pump.

[trunt]

As the author of the article referred to. The reason I have an EWP fitted is that the well respected Stag specialist who re-built my engine, will not undertake such work without fitting an EWP. This being due to inferior re-manufactured pump parts.
The result of the way the Davies Craig system is programmed, is a slower engine warm up period. Hence the radiator shutter to reduct this period.

I found that installing a thermostat as per Davis Craig FAQ, solves any warmup issues. In fact I would recommend that anyone considering EWP should retain the thermostat, just drill a couple of holes to allow a little coolant through to keep the sensor happy. I have an early manifold so have the bypass blocked but with a later one with the foot you could even retain it as long as you plumb it correctly.

[Goldstar]

The currently available seals for the original water pumps are poor quality and a poor fit so effectively an overwhelming case for an alternative.

The location of the original pump is an example of poor design in that it is located too high and leaves things vulnerable to low water levels.

As it stands the only option is the electric pump as the alternative mechanical pump isn't an option since Stagdad stopped selling his conversion. I think that used the Essex water pump.

Apparently it wasn’t an issue in Dolomites but I assume they had a system with less opportunity for poor system sealing, there are loads of places where our system might not be water tight and therefore not perform well. .

The mechanical water pump is still available from Craig Bartholemew at the Stag Hood Factory.

[jbuckl]

I had 3 gear failures.

nearly lost all enthusiasm for the car….

but invested a lot of time and effort to find worthy pump parts.

have rebuilt about 30 pumps now for members.

the parts I use don’t come from the usual suspects…

however the oem pioneer Weston seal is about £30 now…

I only do this to help pain avoidance for members…

[wilf]

And much appreciated it is Julian.

[LE BRAS]

bonjour
depuis le montage d'une pompe électrique David graig je n'ai plus de chauffage.
Je précise que lors du montage de cette pompe je n'ai pas souhaité remettre le thermostat.
Je suis hanté par les problèmes de chauffe la casse de la pompe d'origine mécanique avait entrainé une casse moteur.
Alain

[Goldstar]

Alain’s post translated.
Good morning
since installing a Davis Craig electric pump I no longer have heating.
I would like to point out that when assembling this pump I did not want to put the thermostat back on.
I am haunted by the heating problems, the breakage of the pump of mechanical origin had led to engine failure.
Alan

[trunt]

Did you connect the heater output hose to the inlet of the new pump with a T connecton?

if you leave it in its original connection to the mechanical pump cover it will not have any flow through the heater.

Avez-vous connecté le tuyau de sortie du chauffage à l'entrée de la nouvelle pompe avec un raccord en T ?

si vous le laissez dans sa connexion d'origine avec le couvercle de la pompe mécanique, il n'y aura aucun débit à travers le réchauffeur.

[vaun_c]

I live in the Caribbean and when I got my Stag the Temp Gauge would not read under 2/3 during normal driving and would quickly 'peg' the gauge in even the slightest traffic. This was in-spite of having an uprated radiator, new fan-clutch, Kenlowe fan & High-mount Coolant reservoir. Our average temp here is high 80's to mid 90's (F), with high humidity to boot. I installed a DC EWP115 kit and it COMPLETELY transformed the car. I programmed it to keep the Temp just a tad below the halfway mark and it absolutely DOES NOT MOVE, no matter how hot the day or heavy the traffic. Being paranoid from the previous overheating, I also replaced the Temp sensor and installed a second Temp Sensor and gauge for the other head and checked the ENTIRE engine and cooling system with an IR Thermometer through all stages of driving and operation ... all readings were consistently within the normal temperature variations expected. Now I'm not saying that the other mods haven't contributed to the overall result however, the DC solved what the others combined could not. Next up is an Engine oil cooler as I expect it will run a little hotter with the new EFI setup once completed.

[vaun_c]

... as an added bonus, the WP & fan runs for a couple of minutes after the engine is switched off which, given the aluminum heads and cock-eyed head bolt / stud design, should (theoretically) greatly reduce warping of the heads by allowing the heads and engine block to cool-down evenly. It also eliminated the hot-start issues with the Holley carb.

[MandM]

Julian where do you obtain the -" oem pioneer Weston seal is about £30 now…"

thanks