PDA

View Full Version : Staying Grounded


AHorseThief
08-21-2011, 09:51 PM
I thought I'd post a PSA on the importance of a good ground. Shortly after I got my 40, it began to intermittentally not want to start. This wasn't the normal crank the engine till it goes not start, but the more troublesome, click of the key and nothing else start.

I started with easy solutions. I pulled the battery, charged it and got it tested. It was "just fine". I checked the alternator output. Once again, no problems here. I chased every loose wire I could find and ensured that it wasn't contacting the frame. Still, every once in a while it simply would not start.

My clue came when I started with the battery charger. I had forgotten to switch it to start mode, but the engine fired right up. This led me to start checking ground. Looking at voltage from the battery to various points on the frame and engine block, I quickly realized that I had a lousy ground.

The as received ground point was on top of the engine and was a copper to aluminum connection. I changed this setup to ground from the battery, to the frame below, and from there to the alternator bracket. I failed however to thoroughly clean the rust off of the new ground points. Once I went back in and cleaned everything up, life was good. If you have intermittent electrical problems, check your ground.

SteveH
08-22-2011, 01:38 PM
Good advice. Even more important with 6v systems on old cars/tractors. IMO, the factory ground cables on FJ40s aren't all that beefy and I replaced mine with a monster-sized cable.