Battery terminals (alternator / charging) Summary: clean em

phedders · Post by **phedders** » Thu Mar 29, 2007 8:10 am

Had a problem with my new bongo.

Seemed the battery was "marginal". Voltage on the battery never got over 12.1v - even with the engine running, in fact with the engine running the voltage kept dropping.

Then I put a DC current clamp on and watched as 30A was drawn for the glowplugs - a huge surge went out as it turned... and then 30A went out (glow plugs still) while the engine was running - nothing was coming in. After 10 minutes the glow plug current dropped off, but there was still 3-5A going _out_ of the battery. All this at idle.

So I was then figuring the problem was one coil of the alternator or the diodes associated with it. Was about to start sorting that out with my Bongo supplier...

... when I figured that I should clean up the posts and terminals. Bit of wire wool later and suddenly I get 13.2-14v while the engine is running, and current flow _into_ the battery! Yey everything is hunky dory, and that alarm with remote start (Falcon EV04+) works fab.

So clean your terminals - probably worth doing once a year anyway.
And big thanks to those on here who gave me hints about finding RPM signals (Simon etc). Also managed to feed a speedo signal to my new stereo and just loving the automatic volume increase as the engine/road noise increases with speed. yey!

mikeonb4c · Post by **mikeonb4c** » Thu Mar 29, 2007 2:24 pm

I have to come clean and admit I probably bought a new battery for Mango unnecessarily just after I got her cos I was in a hurry (about to do 500 miles in an unknown car) and couldnt risk a duff battery. But it was only a 75Ah anyway so better to have it as a spare and have the 95Ah I have in her now. Size does matter - bigger is better.