Is Voltage in Coolant an Issue?

[robeats91t]

I'm not sure what to make of this, but earlier today I was troubleshooting an electrical issue with one of my GReddy gauges--apparently I have a small amount of voltage leakage (0.02-0.05 V) between ground and my ACC and IGN circuits.

Anyways, got that pretty much figured out (I think--got the gauge working again at least) but I noticed something else while I was checking things under the hood. Apparently I've got a 0.25 V differential between my coolant and ground. It was my understanding that the coolant, flowing through the grounded engine, should be grounded as well. I've had a friend tell me that he "knows a guy" that's had radiators and water pumps eaten up by stray voltage in the cooling system--sounds like an urban legend to me, but I have no experience with it, so I'm not sure what to believe. I also read tonight in a google find on the subject that more than a 0.3 V voltage in the coolant (at least in motorcycles) indicates that the acid content of the coolant is too high, and that it is in need of replacement. How can this be? I did a coolant change of 50/50 coolant and distilled water + bottle of water wetter less than 6 months ago...

I plan on adding a few more grounding straps tomorrow, but does anyone else have any suggestions?

Thanks!

 

[supra90turbo]

Stray voltage traveling through your coolant is a bad thing. You MUST get it taken care of right away.

 

[robeats91t]

Will do. I hope no permanent damage has occurred--I don't drive that much, but when I do sometimes it's for hours on end...

I plan on redoing the stock ground straps and adding a few of my own. I noticed my brother's truck has some pretty serious looking braided grounding straps, so I may check with autozone to see what I can find--I can only crimp so big a wire myself...

Also, found this article on Popular Mechanics explaining how to check for stray voltage in the coolant system, if anyone's interested...

EDIT: Anyone have any good experience with radiator flushes? I have a bottle of Xerex Super Flush sitting patiently on my garage floor, but I'm afraid to use it because I don't want years of gunk to block any water passages...

 

[Nick M]

Two dissimilar metals in acid is a battery. That is why you are getting a voltage reading.

 

[koulee]

Well you do have a smallish ground wire at the rear of the block passenger side. You could bolt up a much thicker gauge wire there.

 

[IJ.]

Check all of your grounds.

If the car has had any body work check any grounds nearby to make sure the paint monkey hasn't glooped em.

If your car has an aluminium Radiator FIX this yesterday as the cores are paper thin and in extreme cases will leak within weeks.

Recheck using an analog multimeter Digi's for some strange reason give erratic readings.

Turn EVERYTHING electrical on then get a helper to turn em off one by one while you watch the Multimeter for a change that should give you a clue where to look.