The V8 Owners Forum -

Hello all,

Been considering this for a while, whether or not to go electric water pump on my 4.6 v8 in a westfield.

Im still getting 94-105degc on the hot days......i fitted the largest & biggest capacity rad fan that i could find last year, and made sure its snug to the rad.....so its now pulling well....

Even travelling at about 70mpg, the temps are raising, and it just slowly creeps & creeps.....i know my engines not tuned yet....as I'm still in the running in period....I've only done 120miles since a 5 year rebuild, so I'm still really taking it easy, and not pushing it.....

Can anyone recommend an electric water pump, and whether there's anything else i need to do to fit one, before i waste more time fitting something that would be a waste....

thanks
scott

I think I would rewind a bit and ask the silly questions!
1. Do electric pumps flow more than conventional pumps? If so, how much more?
2. Under normal conditions, the cooling shouldn't be marginal - it ought to have bags of spare capacity for those hot days / mountain climbs / towing caravans etc.
3. My Landie (4.6) has a radiator that is only marginally bigger than the 17" Range Rover cooling fan (the black one with the ring connecting the end of the blades). The cooling circuit is copied exactly from a P38 Range Rover. The cooling is fine.
4. Do you have an airflow problem instead?, i.e. for whatever reason not enough air goes through the rad?

Some pics attached of what I have.

Chris.

I am with Chris - I would be looking for the cause first - electric water pumps generally flow a little less than the equivalent belt driven unit. On your temps, while 105c is getting a bit up there, 100 is about right. My 4.6 runs at about 98.

Chris - on a side - what ECU are you running on that engine??

Cheers

Garry

garrycol wrote: ↑Sun Jul 05, 2020 9:23 am Chris - on a side - what ECU are you running on that engine??

Bosch Motronic, standard ECU for that engine, but tweaked by Mark Adams to be 'standalone', i.e. get rid of all (or at least, most) of the dependencies on the rest-of-vehicle electronics.

Chris.

Thanks Chris - a good option

Is your radiator actually working? There was another thread on here where so much was looked at and eventually the radiator checked and it had slugged up badly and only a few cores were flowing cool and through them. Check the temperature of the whole core not just specific places.

Does all the air going in your front cowl go through the radiator? Or can it escape around the edges? If so seal that off as the air will find the least line of resistance!

Once the air goes through the rad, can it escape freely?

And get the engine tuned, rich or lean can cause the engine to generate more heat

Ian

Quite a few seem to have cooling problems with a Westie - perhaps the owners club etc could help? I'm guessing getting decent airflow though the rad not as simple as it sounds?

Ian Anderson wrote: ↑Mon Jul 06, 2020 5:53 am There was another thread on here where so much was looked at and eventually the radiator checked and it had slugged up badly and only a few cores were flowing cool and through them.

That was me - viewtopic.php?f=12&t=14901 - and what an experience that was. In the end it was all down to a blocked rad. Read the posts and see what I did to solve the problem. I even considered an electric pump but as above, look at the problem first.

Ian Anderson wrote: ↑Mon Jul 06, 2020 5:53 am Is your radiator actually working? There was another thread on here where so much was looked at and eventually the radiator checked and it had slugged up badly and only a few cores were flowing cool and through them.

I had the same. My P38 Range Rover started to get marginal on cooling, and it turned out that about 50% of the radiator tubes were blocked up with sludge in the top tank!

Chris.

Best place for an electric pump, is on an electric car lol

As others have said I would be looking to sort out the issue first - at 70mph cruise an electric pump won't help; unless your getting belt slip! in which case sort the belt slip issue. An electric pump may help low speed heating issues.

My Dax Rush 4.6 V8 (similar nose cone area) has a big intercooler blocking half the rad and cooling is fine cruising at speed. Gets more marginal in traffic at slow speeds on very hot days.

What's your cooling circuit like? can you post pictures?
Do you have good belt wrap/tension around the water pump pulley?
Is your rad partially blocked? check all over with infrared temp sensor.
Air in the system?
How have you plumbed in the heater ports?

Tom.

Do you have a heater core fitted to Demi’s the screen?

Could it be that that circuit allows enough fluid flow to mean a sizeable volume is circulating that way and avoiding the radiator?

Just another thing to consider!

Ian

Ian Anderson wrote: ↑Tue Jul 07, 2020 7:45 pm Do you have a heater core fitted to Demi’s the screen?

Could it be that that circuit allows enough fluid flow to mean a sizeable volume is circulating that way and avoiding the radiator?

Just another thing to consider!

Ian

Easy to test - just clamp off one of the heater flow or return pipes (unless he is using the heater flow path as a bypass circuit?) - but I couldn't see heater pipes in a photo of his engine bay?. If there is no heater then how has the heater flow/return ports being dealt with? just blanked of? or looped together?

Seight-V8 wrote: ↑Sun Jul 05, 2020 8:06 am .....i fitted the largest & biggest capacity rad fan that i could find last year, and made sure its snug to the rad.....so its now pulling well....

Is your fan shrouded? It doesn't really matter how snug it is to the rad, it matters that ONLY the air across the rad passes through the fan, not the air from behind the rad and around the fan, and a shroud that encloses the rad to the fan achieves that end.

Silly question I know, but is your fan drawing air from the front and pushing it towards the rear?
If not the fan is working against the natural flow of air.
Been done before and one bloke in a gt40 actually managed to get one fan blowing and one fan blowing back, no wonder he had so much difficulty at low speed!

Ian