Temp switched relay?

[MAGN1T]

If it was me doing it, I'd use the motor speed controller kitset from jaycar. With minor modification speed is controlled by 0 to 5 V analogue input which can come directly from a thermistor (temp sensor from pinch a part) mounted in an apprpriate place.
It'll directly drive a big meaty pump.

Steve

[Dell'Orto]

Its for the MR2, so not a race car, it'll see plenty of road tripping too.
MAG1T - cheers for that, will investigate that

[neo]

Jaycar frequency switch... $45 http://www.jaycar.co.nz/productView.asp ... rm=KEYWORD

is there no speed signal going to the ecu at all in the old mr2's ?

could get funky and use a abs sensor signal...

[sergei]

Jaycar frequency switch... $45 http://www.jaycar.co.nz/productView.asp ... rm=KEYWORD

is there no speed signal going to the ecu at all in the old mr2's ?

could get funky and use a abs sensor signal...

There is a speed signal there... should be at least.

[Mr Revhead]

I doubt heat soak would be an issue on a road car if you had a proper sized system. Would have to sit there for an age to heat up everything.
Radiator would still cool a bit when stationary.
Imo the simplest options are running 100% (I did that on my AW11)
Or go with the temp switch, if you can find a lower temp switch

[Dell'Orto]

Jaycar frequency switch... $45 http://www.jaycar.co.nz/productView.asp ... rm=KEYWORD

is there no speed signal going to the ecu at all in the old mr2's ?

could get funky and use a abs sensor signal...

Yeah think there is, but the gen 1's are cable speedo. Though actually, the power steering is speed sensitive, so it must take a signal from somewhere. Could use that to switch by RPM

Warwick - trying to avoid running 100% to help prolong pump life. Will only use a Legacy pump to begin with.

[Boosted_162]

Warwick - trying to avoid running 100% to help prolong pump life. Will only use a Legacy pump to begin with.

Are you really gunna be driving it enough to have to worry about pump life? Im guessing this aint your daily?

My old RC one had already been modded before i got it to run the pump fulltime.

[Dell'Orto]

Probably not, but with a 2nd hand pump its probably worth it

[Boosted_162]

Legacy pumps are cheap

[Dell'Orto]

Oh absolutely, but it would suck if I were at the drags and it shat itself

[sergei]

Jaycar frequency switch... $45 http://www.jaycar.co.nz/productView.asp ... rm=KEYWORD

is there no speed signal going to the ecu at all in the old mr2's ?

could get funky and use a abs sensor signal...

Yeah think there is, but the gen 1's are cable speedo. Though actually, the power steering is speed sensitive, so it must take a signal from somewhere. Could use that to switch by RPM

there is output from speedo to ECU (purple-something wire).

[Dell'Orto]

Excellent, cheers chap

[matt dunn]

Do you realise that stop starting a pump all the time
is a lot harder on the pump than running it all the time...........

[gt4dude]

a little story about water pumps...

my stock st205 water pump failed, and i didn't realise it. it threw a code 54 which generally means the water level is too low, and the level sensor tripped to throw the code and the check engine light.

now ive known this sensor in the past to be troublesome, it's really funny about the way you fill it up to keep it happy, you have to do it with the engine cold so you can fit the most water in, you have to blip the throttle so the pump activates and the water goes down and you fill to the top, let all the air bubbles out and you make sure you replace the cap before the pump switches off, anything less and you'll be riding on a CEL and limp mode. and this doesn't always keep it happy, it can still be quite temperamental.

anyways... so knowing of my troubles, i just decided to heck with it and i cut the wires to the sensor and bridged them together to fool the ecu into thinking the IC system is always full. now, alot of what ive read indicates that if the pump fails it will throw its own code 54 independently of the level sensor, this is why i had no hesitation to do the bridge mod. well i found out the hard way this isnt the case, the pump will remain silent to the ecu even if it doesn't move a drop, it relies on the sensor working to tell the ecu that the water level is low because its not moving water so the system isnt under pressure.

my failure to notice a faulty intercooler pump i hold responsible for my engine later overheating and subsequently burning the oil seals in the exhaust side of my turbo causing the car to smoke like a motherfer

[Mr Revhead]

Failed intercooler pump won't cause your engine to overheat or your turbo seals to fail.

[gt4dude]

Do you realise that stop starting a pump all the time
is a lot harder on the pump than running it all the time...........

wouldn't think so on an electric motor?

[gt4dude]

Failed intercooler pump won't cause your engine to overheat or your turbo seals to fail.

that's what i've been told by my mechanic, but theres no other way to explain it out of the blue, in 2 years i've owned the car, it has never overheated after a 1 hour trip cruising along and all of a sudden needle above the letter H. especially since the coolant was flushed and changed 4 months prior.

[matt dunn]

Do you realise that stop starting a pump all the time
is a lot harder on the pump than running it all the time...........

wouldn't think so on an electric motor?

Yes you would, most current draw on any electric motor is on inital startup when you apply power and the armature is not yet turning.

That's why in general an electric motor draws up to 5 time the run current on startup.

And the brushes dont just wear at a set rate as they rub against the armature.
It's not like you can say 125 million revolutions and the brushes will be worn out, the amount of current through them affects the wear rate.
And the pump will be working harder to get the water to flow than it does to keep it flowing.

[gt4dude]

what i'm told is that it's a $5 bearing that wears and you can pull it apart and replace that bearing and its good as new.

i went the route of a brand new pump alltogether since it was reasonably priced