Improve Bad Ground Connections
Here is a note from Jim Loomis about bad fixing bad or corroded
ground connections. He warns us that he is not an electrical
engineer, but the advice makes great sense to me. Thanks for the tip!
See his project here
Reproduced with permission:
In the description, you should substitute 3M Scotch-Brite for steel
whool which can leave small bits of steel that will encourage rust to
form.
Subject: 912 Electrical Problems
Date: Sat, 7 Jul 2001 08:41:06 EDT
Hi,
I love your site! I have a '68 912 that I have owned since '92. I am
just finishing up an extensive redo which included taking the car down
to every last nut and bolt, welding in new pans, rockers, etc.. I
painted it this spring and am in the process of putting it all back
together.
I am writing because I noticed that your car seems to have its share
of electrical problems. 912's have 8mm studs welded to the body to
serve as ground terminals in many locations. Even though the
connections may appear to be sound, there may be corrosion between the
connector and the washer that is welded or brazed to the body. I
think that the washer is copper. When I disassembled my car I found
all of these connections to be corroded. On reassembly, I am sanding
them so that they are bright and using an electrically conductive
paste to help improve the connection.
It sounds like some of your problems might be related to bad grounds.
Have you ever had a trailer with a bad ground? The lights do strange
things, because the current has to follow an alternative path, usually
through the other filaments in dual filament bulbs.
Anyway, I'm not an electrical expert or anything, this is just a
suggestion that you might try. There are at least 5 of those ground
terminals on your car. In the engine compartment behind the voltage
regulator. Underneath the car, a strap that connects the transmission
to the car body- this is a very important one, because it is heavy and
grounds the starter. If this fails I am told that the current from
the starter follows a path through the clutch cable, causing its early
demise. I don't know if that's really true, however. There are
ground terminals in the luggage compartment in the front underneath
the carpet on either side, these are the closest to the headlights.
If your headlights are dim these could have something to do with it.
I think that there is also one closer to the fuse panel, and there
also might be one where the relays sit underneath the driver's foot
panel.
Good luck with everything, I am jealous of anyone with a running 912,
I haven't driven mine since I took it apart several years ago. Maybe
soon,
Jim (near Syracuse, New York)
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