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How to properly install an Electric Water Pump with Zero issues!!!

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Some of you know i switched to a Davies Craig EWP (electric water pump) not long ago EWP150 to be precise but the model is not a concern here.

I found an issue with doing this swap that NO ONE has ever mentioned previously here and well in fact anywhere online! So I am here to tell you what issues i had and how i solved them with a little thinking and problem solving.

When you shut the engine off i noticed a loss of coolant in the swirl pot and first thought head gasket! After many checks it turns out the head is below 10% loss so i was happy. Then i resorted back to the why i was having excess pressure in the upper rad pipes after its all cold for days? Then i looked at the oem housing and figured the problem out! Its as simple as a BYPASS!!!

So the factory housing allows the high pressure side to by pass the thermostat a bit and go straight back to the pump and this circulating the high and low around and around. This creates a vacuum inside that draws the water back into the system once its cooled down from the recovery tank and mine was not doing this because "you guessed it" I had NO bypass! Not knowing this was a thing as nothings mentioned anywhere on the webs, I did an easy bypass from swirl pot to lower rad pipe, NOTE this must be placed in the lower pipe BUT before the pump and NOT after or you dont have a low pressure zone! anything after the pumps rotor fins is the high side!!! doing this will allow it to bypass the radiator core which is the restriction and push its way through the EWP rotor and back through the head creating my new circulation needed. I can now confirm i have ZERO excess pressure in the upper pipes after only a few hours of running AND i can open the cap to receive FULL water in the swirl pot and also the recovery tanks lower from being used now properly pouring it back into the system upon cooling cycle!

This is a huge result and thought I would share this knowledge as it took me some weekends to figure this out and solve and now it means in future this wont be as much of an issue if anyone wishes to go this route later on!

I have also done a video explaining this on my phone, if its annoying or not great please inform me and i will re shoot it on my action camera and hope it comes out better and less rotations LOL for some reason when filming it locks the screen and does not allow me to rotate without the camera rotating? silly thing

I hope its helpful and later on informative to anyone wishing to go this awesome route.

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You should draw up a basic diagram outlining the circuit. I think that would be helpful for the masses trying to implement the system.

Nice work!
 
You should draw up a basic diagram outlining the circuit. I think that would be helpful for the masses trying to implement the system.

Nice work!
Im sure i can do something basic yes, let me whip something up over the weekend
 
You have an electric water pump that has a temp sensor, remove the thermostat.
 
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