fitting davies craig electric water pump.

Ralphh85 · Post by **Ralphh85** » Tue Oct 07, 2008 8:56 pm

my question is whats the best way of routing water in to the engine.

1 reason for goign for the electric pump is a hope to have the water inlet ont he engine facing up wards rather than down as it is on the pump.

just removing the impeller is a bad solution (i think) because it leaves a bad route for the water to flow through.

im thinking of making a up a custom housing, probably cut out a 25mm ali spacer, (RED) and welding in a bit of ali pipe in tot he side of it (BLUE) then either welding a flat plate on top to cover it or more likely just putting a 2nd gasket in and fitting a 3mm flat plate on top.

good or bad idea???? also i would like to put in a wall on the engine where the green line is, to aid flow, but i dont know how i can achieve this without removing the front to weld to it.

any input much apprciated!

Ralph

Ralphh85 · Post by **Ralphh85** » Tue Oct 07, 2008 9:43 pm

another idea, is to make a little dam where the red line is on the engine, so its flat along the gasket level, probably out of chemical metal, JB weld etc (int he long run i would rather take the front cover off and weld it up properly but i dont want to do this at this stage).

then either cut the water pump where the green line is, and weld a pipe in where the blue is, giving what should be fairly good flow.

or same but make my own cover rather than cutting up the water pump.

im confused.com lol.

Paul B · Post by **Paul B** » Wed Oct 08, 2008 8:21 am

When you see how small the outlet is for the water pump you'll realise that there is no point trying to maximise the water flow into the block. Water merely flows round, not screams through at 50mph

I had mine set up like this, simply removed the impeller and plumbed it in. It is a stock motor, and the smaller of the two Craig Davies pumps, which was the only one they did when I got mine. I did 5000 miles on the motor with no overheating problems. I had my pump permanently on, though ideally you need the electronic controller to maintain engine temp, or you can do what I did and simply use the stock thermostat and pop a few 6mm holes in it so the water pump is not dead headed when the engine is cold. ity takes a long time to warm the motor up though.

I cut off the snout of the water pump, to save 3" on the overall length of the motor, and blanked it off.

There is a 90 degree elbow off the pump, straight onto the lower rad outlet. The best advice is to keep the pump low, to make sure it is always wet. Too high and your risk cavitation etc.

I did buy a remote thermostat from a Landrover, but never got round to plumbing it in. It would go between the top hose and the bottom hose, effectively bypassing the radiator.

Ralphh85 · Post by **Ralphh85** » Wed Oct 08, 2008 9:09 am

cheers for the help!

maybe i wont worry so much then, also will wait till i get a pump before i make any decisions.

do you know the ID or OD of the pump inlet/outlets?

Ralph

chodjinn · Post by **chodjinn** » Wed Oct 08, 2008 2:21 pm

My set up is EXACTLY the same as Paul B, except rotated 90 degrees on the horizontal to fit with my rad output. Just remove the impeller and block the whole up, job done. Go for the biggest EWP you can afford, and you dont really need the controller (for the expense anyway, I'm running mine without).

chodjinn · Post by **chodjinn** » Wed Oct 08, 2008 2:22 pm

inlets/outlets are 32-35mm IIRCI've got a metre of silicon hose that would suit that i bought but dont need, let me know if you need some bits I'll sell it ya cheap ;p)

Ralphh85 · Post by **Ralphh85** » Wed Oct 08, 2008 3:10 pm

i just bought the 80! £104 from austrailia.

what colour is the silicone hose? if its a boring colour then i will buy it off you!

gonna have a play around with old waterpump tonight, have had 2 people say they can weld the housing so gonna try an be clever with it as to be more efficient.

something along the lines of my 2nd idea.

Ralph

Ralphh85 · Post by **Ralphh85** » Wed Oct 15, 2008 10:35 am

would it be ok to mount this in the front by the rad? even tho the engines in the back?

Ralph

chodjinn · Post by **chodjinn** » Wed Oct 15, 2008 11:16 am

Should be fine in the front mate, mount it at the bottom hose so you get the head of water to aid in the pumping.

The silicon hose I have is blue, samco colour.

I seriously wouldn't bother messing around with the pump other than blocking up the impeller hole, it's not going to have any affect on cooling or water movement IMO.

Ralphh85 · Post by **Ralphh85** » Wed Oct 15, 2008 12:06 pm

chodjinn wrote:Should be fine in the front mate, mount it at the bottom hose so you get the head of water to aid in the pumping.

The silicon hose I have is blue, samco colour.

I seriously wouldn't bother messing around with the pump other than blocking up the impeller hole, it's not going to have any affect on cooling or water movement IMO.

in the bottom it goes then. plus it will be bringing cooler water through it rather than the hot,which might increase pump life slightly.

i am f***** about with the water in, but mostly because the pipe off the old pump goes in the wrong direction, so it gonna be a pig to plumb in.

and its not costing me anything, got pipe free and have just done a favour for chap who can weld it all up for me.

chodjinn · Post by **chodjinn** » Wed Oct 15, 2008 12:49 pm

well free stuff is always a bonus! Get some pics up where yer done ;p)

bodger · Post by **bodger** » Wed Oct 15, 2008 1:13 pm

so whats the advantage of an electric pump then ?

topcatcustom · Post by **topcatcustom** » Wed Oct 15, 2008 2:36 pm

Saves space? Something to worry about? I would put one one as it would take up less space as I need to put a big belt on for the SC but I still have to drive the alternator anyway...

chodjinn · Post by **chodjinn** » Wed Oct 15, 2008 3:52 pm

Ralph has one i guess due to space limitations and the fact his rad is in the front, engine in the back. I'm using one in the MGB because i got it cheap!

Ralphh85 · Post by **Ralphh85** » Wed Oct 15, 2008 4:38 pm

the electric pump means you can locate it where theres more room.

room is very important if it makes the difference of, fitting, and not fitting!

ont he end of the RV8 the pulleys are massive, especially the bit which sticks out in the middle of the water pump pulley, this sticks out 50mm more than everything else, and was going to cause an issue.

removing it also means the belt does not have to line up with it any more, so i moved the lower pulley in more, and moved the alternator further in to.

above all a water pump rpm does not have much to do with the engine rpm so electric ones are more efficent, and also can be controled with a controler which means the pump onyl spins as much as it needs to, rather than spinning and waisting its energy against a close thermostat.

EWP for the win