Electric water pump

[chris385]

Good morning ,

I am in the process of restoring my stag and having read various posts about electric pump installation I am wondering if on reflection you considered this the correct action? Thank you, Chris

[flying farmer]

I have 3 Stag engines and 1 Rover V8 on electric pumps plus 1 more Stag engine with a belt drive pump. Had far too many problems with the original pumps to replace with original. The Rover V8 was done for space reasons

[Lingen]

Chris. Just to counter Flying Farmer, () I have had my Stag since 1990, and the mechanical water pump is still the one that came with the car This has now done well over 100k miles and only the seals have been replaced. There is no question that in the past the quality of the new pumps available was disgraceful, but the one currently on sale I am assured is well made, and has a good reputation.
If you do want to go for an alternative, I would say go for the belt driven one for simplicity and reliability.
Mike.

[jbuckl]

Hello Chris,
Welcome.

If you choose to stay with the original:-
1.Some bearings and seals being offered give poor to very poor results. (also often causing somewhat uninformed criticism of the original design)
2.Make sure to use an rhp bearing & a pioneer weston seal.... the other items needed & readily available are usually ok.
3.Sometimes the original pumps are tricky to remove without special tools. (slide hammer, adaptor & cage - jack)
4.The cover needs careful checking on reassembly to ensure its close but not touching the vanes.
5.Often the underside of the impellor needs a careful skim (on a lathe) to clean up pitting & corrosion.
6.Its straightforward to rebuild if you have access to basic engineering facilities
7.Its easy to damage the skew gear if a hammer is used(!)
8.The impellor can be stuck to the shaft, but its usually easy to remove with a few basic support tools.
9.The impellor bolt is a left hand thread.

Join the soc, its more than worth it to save / avoid experiencing stuff going frustratingly wrong!
Also Private messaging is available to members too.

I think a self fitted mechanical external water pump kit is about £500 with the alternator relocate parts.
I think a self fitted electric external waterpump kit is about £700 with alternator relocate parts.
I think a new original pump is about £300.
A badly rebuilt original pump can do about £1750+ of damage if the gears fail due to high torque to turn.
A properly rebuilt original pump can be done for £70 with all correct parts. (pump only ~depends on condition)

[malc4d]

Has anyone fitted a new mech. or elec. pump and been able to keep the A/C compressor ?

[jbuckl]

Has anyone fitted a new mech. or elec. pump and been able to keep the A/C compressor ?

No I haven't but I did once see a ford mechanical water pump fitted low down on the left, with home-made brackets & hoses / pipes.... it appeared that the aircon pump would still have been ok on that setup.
FWIW I thought it looked far easier to access too.

[trunt]

Has anyone fitted a new mech. or elec. pump and been able to keep the A/C compressor ?

Yes, well not exactly as in the end I decided not to recommission the a/c but if you ditch the mech fan you can mount the electric pump low left which retains the alternator and compressor in original positions. Mine is configured that way and it handles the USA heat absolutely fine.

[trunt]

I went electric as I had no mechanical pump and didn’t fancy removing the inlet manifold if anything ever went wrong with it. As above post I mounted it low left as I had a mind to keep the a/c but to make that easier the mechanical fan has to go so that the right outlet of the radiator can be piped to the left. I can assure you that as long as you have a decent electric fan it is fine, I live in the northeast of USA and temps hit the 90’s and above for 4 months of the year. reports of overheated engine bays are mostly theories, my experience is that it’s fine, especially as the electric pump/fan controller will run a heat soak cycle on switch off.

The only advice I have is that you retain the thermostat, otherwise when running in cooler temperatures it will have issues getting up to temps.


oh, and regardless of electric or mechanical consider a spoiler, helps a lot with cooling

Terry

[StagJonno]

Going back to the original question - yes, I've fitted an electric (Davies Craig) water pump, together with the controller, which also controls the electric fan. Works very well and, in my mind, reduces the additional thermal stresses from the effect of heat soak by running the fan and pump for around 3 min after switching the engine off. Previously, I could see the temp increase to 105+C with the heat soak.

The electric pump also provides appropriate cooling when coming into a 30mph limit after a spirited run on the dual carriageway/ motorway as its operation is completely independent from engine speed.

Can recommend the hose kit supplied by EJ Ward - pricey but makes a very neat job and includes blanking off hose stubs to close off the bypass circuit. You can purchase the pump & controller plus a blanking plug to replace the original pump from there too. Interesting to note that EJ W always fit this electric pump on engine rebuilds as they had too many issues with the mechanical pump.

[bullstarz]

Electric water pump is the way forward, just like an electric fan. They work when you need them at 100% efficacy regardless of engine speed. They are designed to do the job correctly and not just ok. All mechanical engine driven stuff is a compromise by design. A good controller is needed and keeping the thermostat is a good idea, as long as the coolant can circulate in a aux system. Removing the old pump is also needed. But 100% flow at tick-over whats not to like.

[DJT]

The external, belt driven water pump conversion is excellent. Quality, reliable pump driven by proven technology belt, which can be changed at the roadside in the extremely unlikely event that it should break. No complex electronics to go wrong.

[trunt]

The external, belt driven water pump conversion is excellent. Quality, reliable pump driven by proven technology belt, which can be changed at the roadside in the extremely unlikely event that it should break. No complex electronics to go wrong.

Similarly All the “complex electronics” can be bypassed if needed to get you home.