FE-FC Holden Discussion Forum

Does anyone know how to avoid getiing stray currents in the radiator?

Mitch,

Are these stray currents electrical, water, or dried grapes  ;)

Cheers,

Craig.

Dried grapes are currants.  Surely it couldn't be those.  I've heard of cars with trees growing through them in paddocks, but never a grapevine.....

Sure it's not wine in the diff that's the problem? ;)

HI.
I got a terrible electric shock the other day in the Bakery (I am a Baker/Pastry chef). I stepped on a fruit bun & a "CURRANT" ran up my leg!!!!! :o

Get it? ??? :-[

Man, I have been waiting a LONG time to use that joke. Sad, Huh??

Rob

And the fruit-bun in question got sold as a Danish?
I always suspected those ones with the lattice pattern on the top are created by stepping on them in a pair of Dunlop Volleys ;D

I hope someone is going to answer Mitch's question one day soon....  Can you give us any more details about your problem?

cheers
RET

Stray currents "what da"  :o

Mitch
This normally caused by the use of dis-similar metals in the manufacture of the motor, that is cast iron aluminium brass etc.
This is why late model cars can not use plain water in the rediator but must use a coolant mixture designed to suit. It is also caused by poor earthing of the different components in the body / drivetrain.
The way to fix, plenty of good earth bonding connections and the use of a suitable coolant, say the one used for V6 Commodores.
Good Luck
John M

Geez RET that English teacher mum of yours must of made sure you read the dictionary - mine just kept giving me MAD magazines, now wonder I can't spell currents or currants.

FCMayberry is right about earthing, if you have a look at LJ Torana's they have an Earth strap factory fitted from the radiator support panel to the radiator itself for exactly the purpose he describes. Just a couple of connectors and some 2.5mm cable should do the trick. Make sure you remove the paint under the attachment points though.  He is also spot on when he says it doesn't hurt to add a few more. One that's very useful is a link from the Battery -ve to directly to the Chassis - usually the only earth connection (especially on older cars) is the one from the Battery to the Engine Block. Not much good when the engine connects to the chassis via rubber engine and gearbox mounts   ???

Because of the high currents (note correct spelling ;-)) and low voltage in cars any minor series resistance causes a large drop in voltage so it is really worthwhile regularly cleaning battery terminals and any other critical points.

Hope this sorts your problem out.

Cheers,

Craig.

Correct me if I am wrong !!!

Does that sound like OHMS law or what !!!!

ChrisB  8)

I took a few goes but finally I got what I was after.
Stray currents can cause holes in the radiator because when the electrons flow in an electrolyte (Water in this case) from + to - they take with them small amount of the metal. The same theory is used in electroplating.
I assumed that good earthing would overcome this problem but I was also seeing if anyone knew where they could be comming from. (headlights?)
I have a new radiator installed and I don't want to have a repeat performance of the last one.

Cheers
Mitch

Mitch
Apart fromhaving things like the generator,starter motor coil ,distributor attached to the motor. Electrical current will be generated from dis-similar metals and the water acts as the electrolyte, just like a battery.
This is a problem in marine engines, refrigeration equipment which chill water etc and the manufacters place scarificily(spelling?) anodes in the system which get eaten away instead of the metals you don't want eaten.
Suggest you go with the good earth rountine and coolant instead of water and all should be OK.
The reason modern water is different to the old days water is all the chemicals that are placed in it now,of cause if they didn't we would more than likely be a lot sicker now.
Hope this helps
John M

Hey John
It's sacrificial anodes  ::)
Mitch
I've noticed on a couple of my cars (FCs) an additional earth wire from the generator to one of the regulator box mounting screws.
I wonder if GMH did this to stop the stray currents.
Regards ACE :D
P.S  Rob   You must make lots of DOH   ;D

Mitch
In my job as a mechanical engineer we have experienced similar problems with corrosion of cylinder heads, manifolds and radiators in late model cars, even with good coolant in them. The corrosion was caused by eddy currents from the fitting of electrical accessories with insufficent earthing. In all cases we solved the problem by fitting zinc sacrifical anodes used in marine applications. They can be suspended in the coolant or firmly attached to the  cars bodywork. We are currently assessing an electronic rust prevention systen to see whether it will provide the same effect, but won't have an answer for a while yet.
Cheers
Jockster

After a slow start we seem to be getting closer to the problem, and a cure.

I think the real name of the problem is called electrolisis, and not currents.
Much of the later discussion seems to be getting somewhere.
I have never had a radiator eaten away by electrolisis so therefore haven`t had to worry about sacrificial anodes.
What I would suggest is earthing the engineblock to the body with a thick earth braid.
The original connection hose to the fuel pump had a metal braid around it for this purpose but most heve been replaced by the wrong hose.
Daydreamer.

Hi Gents

I have nothing to add, however found this very interesting and will keep this info in mind while working on my car.

Thanks Jim

BUMP!