Radiators

Rosco, how exactly did you measure that? Which MM probe onto where?
Keep in mind that digital multi meters have just pico amps flowing between the probes for voltage measurement, you may have measured some static voltage if you used a digital MM.
Try the same with an old style 50k ohm/volt pointer type meter at its most sensitive setting (0.5V full scale?). If you find the above voltages with that meter you have cause for worry. Maybe time to check and clean all the earth connections. There are quite a few of them, beside the obvious one for the starter motor. The workshop manual should show where they are. Of course, if someone has added to the wiring and connected the earth willy nilly anywhere......
Klaus

G'day,
I read all that stuff recently on this forum about stray currents etc and whilst I'd never previously heard of it, I'm not brave enough to say it's a load of bull-twang.
However, from memory, the bloke who posted the info said you had to drain the rad, flush it several times, then fill it with demineralised or distilled water (I guess rain water would do?) and THEN do the stray current test. I took that to mean that it was not worth the effort simply sticking the + probe into the coolant as presumably this has some sort of stuff in it which would give a false reading. Does anybody else remember reading all that? I thought of doing the test myself, but couldn't be bothered doing all the flushing etc. Anyway, the last time I did a test I failed dismally; and that was after studying hard for 3 weeks!!!!! The test? It was a urine test!! LOLOLOL
I wouldn't worry too much; but then again it's not my jaloppy we're talking about. The way I see it I don't have a stray current problem (because I haven't checked it) so that's one thing I don't need to worry about. Ah; ignorance is bliss!!!

Cheers,
Roachie

A simple wire from the radiator to vehicle body solves this problem. Many cars come with this as standard.

Rosco.
This stray current problem is real, but the way it was explained in the post a few weeks back was very strange. The problem arises if there is a diference in voltage between the engine block and the radiator. THe story about flushing and sticking the probe in the water is misleading, all you have to do is measure the voltage difference between the radiator and the block. Some air con instalers bolt an electric fan directly on to the radiator core and and then earth the fan motor to the core this is the most common cause of this problem. To cure it just run a wire from the radiator to the block. If you place a multimeter probe on a battery terminal you will always get a slight voltage due to the acid which is invariable on the terminal reacting with the chrome plating on the probe. To test this place your meter on the negative terminal and the other lead on the body with nothing swithed on. Eric.