[Joshyboy26]

After some overheating issues on the weekend i am looking towards putting in an inline water pump into my car to aid with flow and help with bleeding etc while the engine isnt running.

The car is a sierra with a 4age 20v and rear mount rad.

Any suggestions on what brand of pump flow etc.

[Gwagensteve]

Bosch. They're 1000x better than the Davies, Craig stuff. I have both.

Steve.

[greyghost]

and risers...... every where risers or you'll never get the air out.

[Gwagensteve]

Yep- definitely ensure there are bleeds on the high points or you can easily have air locks that are almost impossible to clear.

[Joshyboy26]

Yeah i found that out the hard way.

Yeah lots of risers, a bosch pump and lots of bleeding and hopefully itll be good.

Wheres the best place to buy these pumps from?

[Joshyboy26]

Also do any of you guys have a light to tell if the pump is on/off/failed?

[Gwagensteve]

Sorry, can't help with part numbers or a source - I got mine direct through bosch when I had a contact there. Unfortunately, there aren't any part numbers printed on the pumps.

No, I don't have a light to tell me it's failed. It wouldn't be the easiest thing to wire. It's a good point though, I have had one of my pumps fail and wasn't aware it had. Depends if you can hear it too - mine is audible on "ign" because it's just behind me. In fact, I can separately hear the fuel pump prime and the water pump fire up when I key to ign. I listen for it more now knowing one has died.

I run the pump on permanently.

Steve.

[SuziBlu]

Surely an indicator light would not be hard for an Auto Sparky to hook up.

Fan on, light on.

[Gwagensteve]

That's super easy to wire up. I think josh was asking if a light could be set up to go on if the pump failed. That's a bit harder.

Steve.

[SuziBlu]

Steve, if the pump fails, then voltage is lost, so no light ?

[MrRocky]

I have a few mates run them on drag/street cars and general consensus is if your doing lots of km on road they fizz out pretty quick. Mind you that is high hp boosted v8 applications so may get more longevity out of a zook/yota setup

[SuziBlu]

This has me stuffed, they are now stock on some cars, if the bugers stuff up, why would the likes of Ferarri use them ?

[Gwagensteve]

Josh was asking if it could be wired the other way around, so the light came on when the pump FAILED- so like a warning light. This is a bit harder but more intuitive for something where on is the normal condition.

Yep- ferraris are super reliable- they're a great example!

However this is an example of where the OEM part exceeds the quality of the aftermarket offerings. The Bosch pump I use is an OEM pump for heater core circulation in a Volkswagen. They are mag coupled and will need to meet Volkswagen group longevity standards. They retail for circa $180.

The much larger pump used in 7 series BMW's retailed at $800.

Most Pushrod v8 ewp's are designed for track/drag use purely to reduce parasitic loss. They aren't intended for daily driving. Their manufacturers say as much.

[Jezza86]

if the pump impeller fails voltage will not be lost, especially where the motor powers through induction (magnetic coupling)

a ammeter would give a good indication of run/stop and would also allow monitoring of the pump over its life cycle (higher rpm due to failed impeller should suck less amps if its a centrifugal pump)

[got_bar_work]

Or a inline flow switch

[Joshyboy26]

Yeah i was thinking of something however a fairly cheap, uncomplex solution is going to be hard to achieve i imagine.

I am finding it very hard to find the pump you are talking about steve, i think i have found one however the inlets and outlets are quite small ie heater line size. Would this cause issues reducing down to that size at the pump?

Also do you have issues with the pump running when the thermostat is shut? Surely it would pressurise the system quute a bit and put a lot of load on the pump?

[Gwagensteve]

Mine are 19mm OD on the piping. No, it's not a restriction - velocity through the pumps is huge.

I have seen no problem with load on the pumps when the thermostat is closed. You could say the same thing about the factory water pump. These pumps are a circulation pump, not a pressure pump. (think hair dryer vs compressor) they don't produce heaps of pressure. Bear in mind, the cooling system isn't fully functional until it's at near 15 psi anyways.

Steve.

[Jezza86]

When theres no water leaving a centrifugal pump the water is simpily spun within the pump housing causing pressure to decrease.

A pump where this is not ok to do is a turbine pump where the impeller is like a propeller or the fan in steves hair drier. No flow or a blockage throough that will cause so much turbulance in the pump housing you will blow fittings or motors or even crack pump housings

[Gwagensteve]

about 6 years of use tells me the bosch pumps are fine against no flow.

[SuziBlu]

Why not throw the thermostat and use a temperature controller ? A thermo restricts the water a lot, even when open, the inline pumps do not produce much pressure, so its a restriction you can do without.

Without a controller, i cannot see the need for an Inline pump, unless its a secondary.

[Jezza86]

i reckon a radiator bypass that closes off once a set point temperature is reached.

[SuziBlu]

Electronic controller, this will allow a small or large amount of water, ie, as little power drain as needed.

You could simply use a thermo fan type on/off switch gear, set it at a few degrees below your thermo fan, but me, id rather a true controller.

This way you know whats going on, you can have you engine a bit cooler, and so advance ignition, less drag from continuous fan more power to wheels, more advance, more poer to wheels, no solid state fan, all mean big win in the power to wheels.

[Gwagensteve]

There is no need for that level of complexity. My Bosch pump consumes a truly tiny amount of power. Ewp controllers are unreliable from what I've seen/heard.

The power "loss" at the wheels from running the pump full time would not be measurable at the wheels.

Keep it simple.

Steve.

[Joshyboy26]

Yeah far too complex ill just have a switch and make sure its on if the cars running.

Do you think this is yours steve

http://www.amazon.com/Bosch-0392020073- ... dSort=best

[Gwagensteve]

Looks the same. Price is good too. As I said though, there's heaps of part numbers and the numbers aren't on the units.

Those models are intended to be mounted inside the car, so protect it at least a bit from mud and weather.

[SuziBlu]

My point was that they are not designed to run in a static situation, ok parasitic loss may be minimal, but, with a Thermostat, flow rates are much reduced to specifications.

[Jezza86]

centrifugal pumps are used because they are tolerant of low flow/ deadhead situations.
a controller on an electric pump stoping and starting the flow also runs the risk that when the pump is stopped theres no flow past a temperature sensor so the pump wont restart soon enough aand the engine will cook

[Gwagensteve]

Can we get some balance in this discussion re drag/power loss etc.

As far as I can crunch the numbers, in joshyboys car, the effect on performance of the Bosch water pump stalled out is equivalent to adding 350grams of weight to the car.

Thanks for the link to the part number josh- I now have a source for replacement pumps
For my car.

[Jezza86]

centrifugal pump spinning stalled will draw current equal to the friction of the fluid on the pump housing, the turbulance on the outlet and the friction on the rotor. EDIT: and cavitation losses eating you impeller if aperoperiate for the RPM

I.E, not much.

the pump will pull more amps when not stalled, as it is doing work (flicking water out of the pump through the cooling system)

[Joshyboy26]

Im not worried about the amps/ power it will draw, i was more worried about the pressure building up or cooking the water within the pump and the then the pump itself if its running while no water can be moved.

No worries with the part number, its a very hard pump to find specs on but is out of a 2006 vw golf with a 2.8l na petrol engine