Charge cooler pump problem.

[Uk Blown SS]

Hi guys, we are mid way remote tuning a 2012 ZL1 and have high IAT's. I have unplugged the pump, 3 wires, one black (ground) and two brown. Neither or both when powered up run the pump and it wasn't running after a good run. Does anyone have the wiring diagram so I can confirm ? Thank you.

[tartagliazl1]

Did you check for air pockets? If it’s not bled properly the pump won’t come on.

[Uk Blown SS]

I can't get any more coolant in the pipe at the bleed port.

[ZMEnow]

Originally Posted by Uk Blown SS

I can't get any more coolant in the pipe at the bleed port.

Add a reservoir it solves the air problem. Without one the system is designed to be negative pressure filled as recommended by GM. I used a MAC tool pressure’s filler before I added a reservoir. Many just go by chance and fill, drive, fill, drive and hope the pump burps out the air.

[Uk Blown SS]

How does the pump know there is air in there ? The supercharger has been replaced previously so this is a good possibility.

[JB'sZL1]

Not to be a smarta@@: The pump "knows" nothing. The pump is manufactured to push fluid, not air. Even air bubbles will cause less fluid to flow, and will weaken the pump.

If you worked on the system and did not use negative pressure as ZME stated, it is probable you have air trapped in the system. As stated, add a reservoir...it is essentially self bleeding.

[ZMEnow]

Originally Posted by Uk Blown SS

How does the pump know there is air in there ? The supercharger has been replaced previously so this is a good possibility.

I had read in the forum many years ago that the ECU monitors load on the pump based on flow pressure. If it falls below a certain level the ECU kills the pump to protect it. I would have to read the shop manual to confirm but I am too lazy to do that. Here is another cheap option..


https://jannettyracing.com/products/...cadillac-cts-v

[HDRDTD]

Originally Posted by ZMEnow

I had read in the forum many years ago that the ECU monitors load on the pump based on flow pressure. If it falls below a certain level the ECU kills the pump to protect it. I would have to read the shop manual to confirm but I am too lazy to do that. Here is another cheap option..


https://jannettyracing.com/products/...cadillac-cts-v

That's the route I took. Bought one of those and using it couldn't be simpler.

And yes, it really does use an ordinary soda bottle attached to the appropriate connector that mates with the SC's filling elbow.

Simply rotate the fill elbow so it's pointing up, and attach the fill bottle. Fill the bottle with coolant and run the engine for a while , while watching the fluid circulate. If the was any air trapped inside, you should see the system 'burp' when the air comes out and the level in the bottle drop a bit.

When your satisfied that all the trapped air has made it's way out, simply turn off the engine, remove the fill bottle carefully and rotate the fill elbow back down.

Now just take the fill bottle and store it away somewhere so you can remember where you put it the next time you want to use it.

I'd say perhaps use it once a year or so or perhaps more often depending on how hard you drive the car.

Using the fill bottle this way eliminates the need to mount anything anywhere, and the fact that once tou remove the bottle, there will be no additional hardware attached that might be deemed a 'mod' and void the warranty'

FYI, I bought and used the fill bottle at roughly 50,000 miles on my ZL1 with minor track days on it and the system did 'burp' maybe 2-4 small 'burps', and not enough to detect any change in engine operation.

It DID however result in peace of mind for me.

[Uk Blown SS]

All good info that is appreciated, we took the reservoir route, so when it arrives will see how it goes.

[Uk Blown SS]

We fitted a decent remote tank and pipes, I pushed coolant round with some air pressure to ensure the system was full. I can activate the pump through the scan tool, you hear the relay click and the fuse powers up but still no pump action. Driven too, that didn't help either, wondering now if pump has failed, have I missed anything else ?

[JB'sZL1]

One last place to check: with the above being done (good fuse, relay clicking), check to see if you have power at the pump. If so, the pump is fried.

[ZMEnow]

Originally Posted by Uk Blown SS

We fitted a decent remote tank and pipes, I pushed coolant round with some air pressure to ensure the system was full. I can activate the pump through the scan tool, you hear the relay click and the fuse powers up but still no pump action. Driven too, that didn't help either, wondering now if pump has failed, have I missed anything else ?

You pushed coolant around with air pressure would add more air in the system. Assuming your reservoir is at same height as the radiator I would leave the cap open and take the SC fill cap and open it. Take that fill cap hose and twist the downstream bend or loop up so you create an air block. Now fill and watch the coolant fill the reservoir but leave its cap off. Now lower the SC hose and continue to fill until it either comes out of the reservoir or the SC fill port. If it comes out of the reservoir first, close it and continue to fill the SC port.



You now have forced what air that would be in the pump out of the reservoir so the pump shouldn't cavitate on start as the only place you could still have air is in the brick or the HX. Remember this isn't a radiator you are not going to see water rushing by but should see some movement at the SC fill port and bubbling at the reservoir. Hopefully you didn't have an excessive amount of air before and fried the pump.

[Uk Blown SS]

We double checked the wiring all good, so have fitted a Craig Davies high volume pump. Along with a remote tank and plumbing intake temps are back to normal. I always suspected the pump and just over complicated everything !

[ZMEnow]

Originally Posted by Uk Blown SS

We double checked the wiring all good, so have fitted a Craig Davies high volume pump. Along with a remote tank and plumbing intake temps are back to normal. I always suspected the pump and just over complicated everything !

Good deal...