davies craig pump control...

Ralphh85 · Post by **Ralphh85** » Fri Oct 31, 2008 12:29 pm

i got few options of how to control the coolant in my car.

i got a davies craig EWP80, and im not sure weather to run a thermostat or a digital controler. or both. and with maybe the little boster pump to keept he heater circuit going.

main worry is with the heater, as with out the thermostat theres gonna be little reason for any water to go through the heater matrix, as its gonna be easyer for it to go down the rad....

1, run just with the pump and existing 88deg thermostat, this will give good heater, but not so good on efficiency since the pumps runnign all the time.

2, run with the thermostat removed and with the digital controller, this would work the best from engine cooling but not sure how well the heater would work as there will be little flow, and without the thermostat restricting the main flow, i dont think much will flow through the heater matrix? would the EBP completely sort this? my only worry with the EBP is that it will probably reverse the circulation the the main RAD when the EWP is off and run cold water through the heater?

3, my other option is to run the EWP with the digital controller, and fit a lower temp thermostat, say 74 or 82 degree's, so on warm up the main flow of water will be through the heater, then the thermostat will open, and the controller will regulate flow while its fully open. the thermostats restriction would probably help the flow through the heater matrix?

any ideas???

Ralph

Ian Anderson · Post by **Ian Anderson** » Fri Oct 31, 2008 12:49 pm

Ralph
I would not be overly concerned about the heater matrix not getting hot. you will have enough heat coming through from the engine.

What I would suggest is to tap into your 32mm pipes to and from the rad (preferably where the main pipe does a bend) and at that point have a 15mm or whatever take off piece welded in Picture the 32mm pipe going off at 45 degrees and the 15mm pipe continuing straight.

Then the same for the return going back to the engine (2nd y piece)

I would make it in a circuit Engine 32mm pipe Y piece to heater and 32 to rad.
The Rad to 32mm to y piece from heater matrix then to water pump that way the water will only ever flow in 1 direction. (I can see the direction change possibly happening if you do Rad to pump to Y from heater!)

The radiator in effect will restrict the "easy" flow of coolant and so you will get some flow through the heater matrix and need a tap of some sort to stop the flow during the sumer - or you will have hot air throught he vents in August!

And if using the EWP by itself I would remove the standart thermostat so the oump can move water as the controler "suggests"

If you run both pumps then I would run the heater from the standard water pump connectoins and just fit the EWP on the return 32mm pipe from Rad.

Fun these conversions??

Ian

Ralphh85 · Post by **Ralphh85** » Fri Oct 31, 2008 2:28 pm

thing is heat from behind aint gonna clear my windscreen, also its gonna be foam insulated an carpeted on the inside so i dont think that much heat will get through.

good point about making the direct route to the heater matrix and the main pipe coming away at an angle, could help.

if the air is set to cold then it bypass's the heater matrix anyway, so i wont need to stop it.

yeah tis fun

Paul B · Post by **Paul B** » Fri Oct 31, 2008 6:53 pm

In a conventional set up, with the DC pump in the rad hose, you won't have any water flow at all with the thermostat closed, which may or may not harm the pump. I drilled 4 x 6mm holes in my thermostat to allow some circulation at all times. It takes ages to warm the motor up though, in cold weather.

Another method is to use a Landrover remote thermostat (and the normal 'stat removed) which will bypass water directly from the rad top hose to the rad bottom hose (Tee'd in between the pump and the rad) so your pump can still happily circulate water. I have one somewhere I bought a while back, but never used.

Something like this, but without the hoses:

This way you'll have hot water circulating in the block as normal, until it gets up to temp then it will go through the rad as well. You can maybe leave a restriction, like a big washer, where the original 'stat went and plumb your heater in to some existing fittings, maybe...

Ralphh85 · Post by **Ralphh85** » Fri Oct 31, 2008 8:25 pm

fairly sure the heater matrix flow on the rover is unrestricted by the thermostat?

Ralph

Paul B · Post by **Paul B** » Sat Nov 01, 2008 9:32 pm

Ralphh85 wrote:fairly sure the heater matrix flow on the rover is unrestricted by the thermostat?

Ralph

Yes, but with the stock thermostat installed you'll have no water flow through your motor at all, your pump will be dead-headed, so no heater, until you get up to 'stat opening temperatures. Unless the heater bypasses the thermostat, in which case you'll never get up to temperature as your rad will be flowing loads of water continually?

Running just the pump controller will be your best bet, as flow will be minimal until you get some temperature in there. You'll just need to warm it up properly before giving it any hammer, as the slow water flow may cause hot spots in the heads, apparently.

This is more complicated than I thought