Coolant pump replacement

[muley]

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My coolant pump started leaking.

I shopped around. A similar looking Bosch pump didn't fit. With the connector it was too long

Finally, I settled on a Bosch Water Pump 0392023004, bought off eBay.

This needed a connector. If you use this one

2 Pin Connector Injector Plug A1685452928

it has a white plastic insert which stops it fitting. Throw the white bit away.

Make a little bracket with a bit of metal strip.

Remove the old pump and bracket

Cut of the connector on the loom.

Fit new bracket, plumb in the new pump and fix with a cable tie. Splice in the wiring (black to red!) (black/grey to white!) and Robert's your father's brother

Top up your coolant

Usual disclaimers.

Replacement pump does 900l. per hour older pump 500l. per hour. Glad you asked

[Tuga2112]

id think any more data on the coolant pump would be usefull in the wiki instead.

I need to ge there and add my own solution to it (based on the pump that JamieN used)

[Mxer125]

I've only just read about this!!...

Car has stood for 10 +years as some may know..

Also I've replaced my water pump (cam belt side) so what does this do? And do I need to check it? I'll be honest I haven't even spotted it yet lol.. this again sounds expensive.. ouch!

If needed that it?..

[Tuga2112]

I've only just read about this!!...

Car has stood for 10 +years as some may know..

Also I've replaced my water pump (cam belt side) so what does this do? And do I need to check it? I'll be honest I haven't even spotted it yet lol.. this again sounds expensive.. ouch!

If needed that it?..

no you dont need it.

even if it doesnt work, you dont need it.

it recirculates coolant in the opposite direction of normal flow when the engine is off AND the coolant temperature switch is closed (its the thing that activates the radiator fans)
unless you plan on driving it very hard in warm weather, you are very unlikely to have it come on "naturally".

i believe its purpose is to flow coolant in order to avoid heatsink of the engine after a hard drive when parked.
under normal circunstances, the radiator fans cool down the water so effieicenly that by the time you park theres nothing to worry about.

thats what i recall from reading about the topic, but im sure someone will correct me if im wrong.

[Mxer125]

That's really interesting cheers Tuga, very well explained I do actually understand.. it's quite a cool feature actually I will certainly explore more once I'm on the road.. new tyres come today (Toyo proxy's) so not long now.. cheers mate.

[dapinky]

Yes, as said, the whole point of it is to prevent the turbo from overheating with the engine hot and off. It pushes water backwards through the system and would only be active if the car is hot enough to have the fans on with the engine running, and then turn off the engine......

...... most people are savvy enough to realise that you should keep idling the engine before turning off to allow it to cool anyway (if possible) and the extra pump is for those times when it isn't possible.

The only time i can see it being a huge benefit is on a trackday when you come off track and park up on dry grass or something like that, so you wouldn't want to keep it idling in long, dry grass with a hot exhaust - but even then, by the time you've come off the pit lane and into the paddock, it should have turned the fans off 99% of the time.

Like with many things, it would be nice to have it working, it *may* be some use someday, but probably not worth losing too much sleep over.

[Mxer125]

That's fantastic thanks guys, it's a great relief knowing it's not a major issue if it's not working. I'll certainly explore it and check for flow and leaks and parhaps overhaul or replace at a later date when funds allow, I haven't yet run to temperature yet so my priority now is to see if the fans kick in.. Will see (that might be another thread lol..

Interesting stuff, thanks again guys!!

[Tuga2112]

its a fairly easy part to replace, and the wiring is very straighforward to adapt. I certainly recorded a video when i did the job, but i would have to check my channel to confirm if it made its way to the public domain.

[Hector2021]

This was one of the early checks i did on my car once i picked it up. You wont know if the pump works until the car gets that hot it needs it once you have switched it off after a 100mph blast before you race into the pub for last orders.
My TT had one fitted and i never heard it run in that car either.
Ive seen a couple of cars with it removed and bypassed by pipework as a get around to replacing a leaking unit.
I checked my pump using the fan thermostat switch to earth with the ignition off and nothing happened. It turned out that the pump had leaked coolant (over many years) into the motor and turned the internals to rusty mush.
I found an identical replacement off ebay but it came with a molded Bosch fuel injector connector, I just bought an equivalent opposite connector from ebay and swapped the original flying lead plug. Now works as it should but will probably never work through demand. I understand its very limited need too, but i just wanted it as a working item and it wasnt a difficult or particularly expensive problem to solve.