Electric Water Pump

JohnnyN

Does the electric water pump for the pre-rad charge cooler run all the time or does it cut in and out when on/off boost?

Daz checked the feed to my pump this morning and there was no power to it whilst on idle. We traced the wires back to a relay and a 10 amp fuse. The fuse is fine.

Answers on a postcard please!

notsure.gif

vocky

should be running all the time the engine is running :thumbup:

JohnnyN

So what do you think is wrong? Am I putting the engine at risk? I don't know how long this has not been working.

exmantaa

Should be running all the time.
No chargecooling can be very dangerous, as the Courtenay remaps don't measure the manifold air temp!

Check relay feed +12V (fuses etc.) with a simple volt meter.
Check the relay by making a jumper cable from the +12V feed to the signal feed. Should run then.
Check relay signal wiring. Normally spliced from fuel pump wiring.
Also check the grounds!!

JohnnyN

exmantaa said:
Should be running all the time.
No chargecooling can be very dangerous, as the Courtenay remaps don't measure the manifold air temp!

Check relay feed +12V (fuses etc.) with a simple volt meter.
Check the relay by making a jumper cable from the +12V feed to the signal feed. Should run then.
Check relay signal wiring. Normally spliced from fuel pump wiring.
Also check the grounds!!

This pump might have been this way for months!

Sorry to be a pain but can you explain in more detail of how to check the relay? I'm a complete novice when it comes to electrics.

JohnnyN

Would it be okay to put a live feed straight to the pump just to prove a point?

Daz

The bit that puzzled me john was why it takes a feed from the coil pack......and also the other wire from that relay goes to the extra injector area....

vocky

coil pack wire is probably the relay coil +

you will probably have a +12v coming from the starter motor via a fuse to the relay, then the output of the relay goes direct to the pump

the easiest way to test the pump is to run a live direct to the + and a ground to the - :thumbup:

ps: not unknown for those pumps to play up :roll:

Daz

We have no live feed to the pump neil.....fuse in the power cable in the relay box is good,.. didnt want to go digging into the wiring to far as wasnt sure if it was a constant feed,or wether it came on only when on boost...

vocky

sounds like a problem with the +12v supply notsure.gif

Daz

Think another trip over is in order john.....will whip out ure airfilter etc and trace the wires back.....

BURT150

Thats might of been the cause of your high engine temps not so long ago?

4 pin relays are cheep as chips :thumbup:

I might even have one in the garrage?

JohnnyN

Alrighty then chaps!!! UPDATE!!!

Just been out to the garage in the cold and dark whilst you've been hear racking your brains for me and I have found the problem!!

I checked the feed plug to the pump and it was still dead.

I removed the relay cover and set about the wiring and that fuse holder. I removed the fuse to find that one of the blades was burnt and the plastic around the fuse distorted by heat. The fuse was quite difficult to remove.

I then tested resistance (i think, set meter to omega sign, sorry for my ignorance) and the fuse completed the circuit. I then replaced the fuse with a new one and then tested for volts on the exit side of the fuse holder and I had +14v with the engine running.

I then went back down to the pump plug and checked the terminals again. This time I had +14v!!! I checked this 5 times for the sake of my OCD and then reconnected the plug to the pump. Whilst doing so I held the pump in my other hand and I felt the water pump spring to life!! Its alive!!!!!!!!!

Thanks chaps for all your help and suggestions and thanks Daz for checking this out today. :thumbup:

Question is now, how long for and what damage has been done??

Daz

Well the fuse melting aint a good sign.....obviously it drawing more current than the holder/fuse can handle...

JohnnyN

BURT150 said:
Thats might of been the cause of your high engine temps not so long ago?

This had crossed my mind many times this afternoon. Especially when Jon said that he was getting inlet temps of 61`C on Tech2.

Here's the science bit.....

BURT150

Not good but at least you know what it is. What wattage is the pump then?

JohnnyN

Pass!

I'm going to give Jon/Mark a call on Monday morning to see if there's a fix for this to stop it happening again and to see if this could have been contributing to the high temps??

BURT150

It wouldn't of helped it!

Just saying about the watt of the pump that way you can work out the cable and fuse that should be used in comparison to what you have.

JohnnyN

Morning all! I've woken up with an idea. I think it would be an idea to add an LED to the power feed that runs to the pump. I can hide it in my centre consol arm rest. As long as the LED is illuminated, it will show that the power to the pump is live.

Would this be a good idea?

vocky

the led is a good idea, but why not fit a temperature gauge to the coolant circuit, then you can monitor the temps 😃