craziest LS swap electrical problem ever recorded

[bradf74]

68 Camaro with HOT ls3 running the GMPP ecu and wiringkit. 6 speed manual. Car has about 2500 miles and my Entropyradiator starts leaking. I checked allmy hoses and discovered it was coming from the radiator. I called entropy and they are shipping me anew radiator because of their lifetime warranty. They told me that I might have electrolysisand to look into that. Sure enough Ihave .5-.6 volts coming through the antifreeze in the car. Testing by 1 lead of voltmeter in the fluidwhile car is running and the other to a frame ground. I run 3 new grounds- front of motor to frame, trans to frame andNEG battery to frame. There was alreadya ground to frame from the battery, but I figured a new wouldn’t hurt. So I checked and still .6 volts. I pull a couple fuses and check with car not running,key out of ignition still .6 volts. Nowthis is where it gets interesting. IDISCONNECT THE BATTERY (both POS and NEG leads) and still .6 volts at theradiator. At this point I think my meteris bad. Nope. Neighbors meter reads samething.
So do I have an electrolysis problem, and where the devil isthe voltage coming from?

[Motorcitydak]

Need to use distilled water when you mix with the coolant, tap water contains metals that can do such things (or just buy the pre-mixed stuff). I personally am running Evan's waterless coolant, it costs a lot more but has a much higher boiling point so no issues with hot spots in the engine block.

[bradf74]

So the 50/50 mix of Prestone from Auozone will be mixed with distilled water?

[Motorcitydak]

Has to be

[Timmah]

When running all the different combination of metal in the coolant system has produce a battery by reaction to each others (electrolysis). It will eat away any aluminum parts in the coolant system. Check into the below part. This will sacrificial part now and should clear the problem.

Flex-A-Lite/Radiator anode includes zinc anode brass plug

Part Number: 32060 $19.99

[icemanrd19]

What happens if you remove the radiator from the car? Still have the volts? As far as grounds go i have the following

1. Passanger side from to firewall
2. Passanger inner fender to subframe
3. Drivers side head to steering column floor cover bolt
4. Drivers side subframe to inner core support bolt that holds my radiator
5. battery to passanger floor panel pass thru that connects to my subframe since my battery is in the rear
6. Battery to trunk hinge
7. Drivers side inner fender to E-brake firewall studs.

[1989GTA]

I know on my EFI car they recommend a Y configuration to prevent ground loops. This is probably not your problem but I will list it anyways. The engine being the center of the Y. Engine to frame. Engine to chasis. battery negative to block. Make sure the ground wires are plenty large enough. Can't hurt to have extras in the same configuration.

[bradf74]

The new radiator is not here yet so I have not tested with the radiator out of the car, but i can't find the voltage anywhere else other than the fluid. I wouldn't know where else to test.
All grounds that I put in are 10 gauge wire and I made sure I had good metal on each. I will add more grounds as suggested, but that still doesn't explain the stray voltage with the battery unhooked unless it is the fluid itself as suggested. I will put an anode on the new radiator, but I wanted to alleviate the problem before I put the new one in. i am not sure how long the anode would last.

[Motorcitydak]

an anode is a good idea as a band-aide 'let's hope this doesn't happen again' and some corrosion will be present on any other metal engine parts may have as well as the fact that you will have a hard time getting all the old coolant out. Bottom line tho is just to put the right stuff in this time. When you drain the old stuff out, try your best to flush it all. Try a large volume of air, the discharge from a shop vac with the hose connected to a radiator hose with the thermostat removed should work ok.

The voltage you are seeing, as you have tested, has nothing to do with your car's 12 volt battery. Instead it is from the one you unwillingly created with your mixture of coolant and the aluminum in the radiator. If you take the radiator out of the car and keep coolant in it, you will still see that voltage present. Still this is a good time to be sure that all of your grounds are in place as needed and in good condition

[icemanrd19]

i used the factory straps
http://www.firewheelclassics.com/sto...pID=&SKU=WRGS2

[bradf74]

This morning it still had .6 volts so I removed the radiator in anticipation of the new one arriving early this week. The fluid had .3 volts in the stream as it was leaving the radiator out of the drain plug. After the rad was removed, I removed the thermostat, jacked up the back of the car and hooked a leaf blower to the upper radiator hose. that got an additional couple pints out of the system. Will post an update when the new rad is installed.

[MonzaRacer]

Honestly I prefer installing Evans coolant, 375F deg boiling point with zero pressure, I just have them use 4 psi to keep fluid in system.
If not use G05 instead of plain coolant. I like to mix my coolant little heavy, 60-70% use a tester that shows over concentration of coolant.
The anode caps are great to help out. You can also add an extra can of water pump lube , most of them have anti-corrosion additives.

[cpd004]

Honestly I prefer installing Evans coolant, 375F deg boiling point with zero pressure, I just have them use 4 psi to keep fluid in system.
If not use G05 instead of plain coolant. I like to mix my coolant little heavy, 60-70% use a tester that shows over concentration of coolant.
The anode caps are great to help out. You can also add an extra can of water pump lube , most of them have anti-corrosion additives.

Evans is great stuff!