Electrically controlled water pump
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alexanderfoti
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Electrically controlled water pump
Has anybody thought about using an electrically controlled waterpump with a thermostat.
Delaying the pump coming on, would allow the engine to warm up quicker, and therefore be more efficient. Set a stat to turn it on when it gets to 50/60/70 degress.
Any thoughts?
Delaying the pump coming on, would allow the engine to warm up quicker, and therefore be more efficient. Set a stat to turn it on when it gets to 50/60/70 degress.
Any thoughts?
- Diesel Dave
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Re: Electrically controlled water pump
I've seen one fitted to a 650 Beemer 'cos the original gave up (does happen if you use the wrong coolant apparently).
Fitting seemed to involve a lot of JB Weld & Silicone....

Fitting seemed to involve a lot of JB Weld & Silicone....
- coachgeo
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Re: Electrically controlled water pump
Not sure what your getting at here. Does not the thermostat do what your wanting already? Engine's pump moves coolant thrur radiator and back to pump in a loop till engine is warm. When engine gets warm thermostat opens itself to allow coolant to move thru the block/head. Is there some other benefit to electric over OEM pump your trying to achieve?alexanderfoti wrote:Has anybody thought about using an electrically controlled waterpump with a thermostat.
Delaying the pump coming on, would allow the engine to warm up quicker, and therefore be more efficient. Set a stat to turn it on when it gets to 50/60/70 degress.
Any thoughts?
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alexanderfoti
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Re: Electrically controlled water pump
Hehee I can imagine. I have contemplated it on my K100 when it gives up, but so far so good!
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alexanderfoti
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Re: Electrically controlled water pump
The new BMW and Mercs use this to increase engine efficiency.coachgeo wrote:Not sure what your getting at here. Does not the thermostat do what your wanting already? Engine's pump moves coolant thrur radiator and back to pump in a loop till engine is warm. When engine gets warm thermostat opens itself to allow coolant to move thru the block/head. Is there some other benefit to electric over OEM pump your trying to achieve?alexanderfoti wrote:Has anybody thought about using an electrically controlled waterpump with a thermostat.
Delaying the pump coming on, would allow the engine to warm up quicker, and therefore be more efficient. Set a stat to turn it on when it gets to 50/60/70 degress.
Any thoughts?
For example, my mums C250 CDI has a magnetic clutch on the water pump.
The pump doesn't engage when you start the car, only once the engine coolant has warmed up slightly, to increase fuel economy.
If I am using an engine that doesn't have a water pump, or uses an electric water pump, then it should be simple to increase warm-up efficiency slightly by delaying the pump turn on.
- coachgeo
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Re: Electrically controlled water pump
first..... I'm going to assume what I say below is wrong. The engineers that did it are way smarter than me. That being said though.... why they really did it and how the Auto manufacture's ad agency pimps why they did the change could be very different.
so lets think here... they "said" it was done to improve warm up rate... hmmm, really? since when does the engine working less hard (not pushing coolant around) make it warm up faster???
Could it improve fuel mileage during the time period of cold to warm.... well maybe... engine not working as hard but geez the savings would be very minimal.
so lets think here... they "said" it was done to improve warm up rate... hmmm, really? since when does the engine working less hard (not pushing coolant around) make it warm up faster???
Could it improve fuel mileage during the time period of cold to warm.... well maybe... engine not working as hard but geez the savings would be very minimal.
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BertTrack
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Re: Electrically controlled water pump
No need to assume. It's all explained. 
https://daviescraig.com.au/electric-water-pumps
The 80 version was installed on the Track unfortunatly without any type of regulation and full power from the moment you turn the key. (Not very good with a small battery)
Since the modern engine all run at higher rpm and more fuel consumption when cold it's worth it to not have the losses of that pump (which is much higher at those high rpm's) during that time.
Heating up the catalytc converter etc. And with a diesel it's very efficient to heat up at least the burn space on a fuel air ratio as lean as possible. Aka idle. Especially when the cilinder and head is cold overfueling may not burn as nicely with the walls and head being very cold still.
In my car where i monitor coolant temperature, oil temperature, turbo boost, calculated load, direct fuel consumption etc i see a big difference in fuel use with a cold (below 50c coolant) and warmish engine. But i get the best mpg only when the engine is fully heated through. Meaning oil is over 90c The difference is ussually 1 to 3 liters per 100km. Depending on speed you have. Where the that difference is bigger at higher speeds.
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https://daviescraig.com.au/electric-water-pumps
The 80 version was installed on the Track unfortunatly without any type of regulation and full power from the moment you turn the key. (Not very good with a small battery)
Since the modern engine all run at higher rpm and more fuel consumption when cold it's worth it to not have the losses of that pump (which is much higher at those high rpm's) during that time.
Heating up the catalytc converter etc. And with a diesel it's very efficient to heat up at least the burn space on a fuel air ratio as lean as possible. Aka idle. Especially when the cilinder and head is cold overfueling may not burn as nicely with the walls and head being very cold still.
In my car where i monitor coolant temperature, oil temperature, turbo boost, calculated load, direct fuel consumption etc i see a big difference in fuel use with a cold (below 50c coolant) and warmish engine. But i get the best mpg only when the engine is fully heated through. Meaning oil is over 90c The difference is ussually 1 to 3 liters per 100km. Depending on speed you have. Where the that difference is bigger at higher speeds.
\
Last edited by BertTrack on Mon Jun 15, 2015 3:57 pm, edited 2 times in total.
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alexanderfoti
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Re: Electrically controlled water pump
It does seem to be a combination of changes in the cooling system. The engine, OM651, also has a 3 stage electronically controlled thermostat.coachgeo wrote:first..... I'm going to assume what I say below is wrong. The engineers that did it are way smarter than me. That being said though.... why they really did it and how the Auto manufacture's ad agency pimps why they did the change could be very different.
so lets think here... they "said" it was done to improve warm up rate... hmmm, really? since when does the engine working less hard (not pushing coolant around) make it warm up faster???
Could it improve fuel mileage during the time period of cold to warm.... well maybe... engine not working as hard but geez the savings would be very minimal.
I think the reasoning being that if the water in the block is left still, to heat up first, the engine as a whole will heat up much quicker.
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alexanderfoti
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Re: Electrically controlled water pump
Thats a good read there! Many thanks.BertTrack wrote:No need to assume. It's all explained.
https://daviescraig.com.au/electric-water-pumps
The 80 version was installed on the Track unfortunatly without any type of regulation and full power from the moment you turn the key. (Not very good with a small battery)
I can imagine having it on the whole time isnt great for starting. Im sure there is a pin that goes live from the smart ECU when the engine is started, you could use that to drive a 5v relay
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BertTrack
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Re: Electrically controlled water pump
I went for a mechanical pumpalexanderfoti wrote:Thats a good read there! Many thanks.
I can imagine having it on the whole time isnt great for starting. Im sure there is a pin that goes live from the smart ECU when the engine is started, you could use that to drive a 5v relay
