I am curious if with all the different hands that have touched my G through the years whether the earth/ground straps are actually connected as they should be and where they should be.  Here is a photo of my layout at present.  I have seen different variations at past treffens, so I have to question mine.  I have no other projects at hand so I thought I would revisit the troubleshooting of my flickering gauges....again.

From the photo shown, does it look right ? 

Mike 

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Thanks all. I did replace and or securely connect the daisy chain from battery to starter and should have said so in my post, however, I may try the wire to the shock mount even though I am very confident all is in order on the corrosion free mounting points to the starter. I also did what Amzimmy did which did not solve the problem. I ask regarding these ground points due to all the differing configurations of these little ground straps i have seen. I am also "casually" attempting to solve my flickering, that is, I am not going to tear things apart and make a major project at this point, but looking for the obvious easy stuff that I may have overlooked prior.

Mike

P.S. That is the ATE Blue DOT brake fluid that you see...not gear oil or Jaegermiester in my brake reservoir.  

I probably ought to start another thread with the "flickering gauge" title where maybe someone might chime in with something completely insane of which may be the missing link no one has thought of or done.  Soooo, to begin the detective work we know this:

1.The flickering gauge thing is not just prone to the gassers...which (at least for my purposes) could rule out the distributor. Diesels and Gassers are both prone.

2. The fuel gauge flickers when activating signals,hazards, and applying brake.

3. The temp gauge does not flicker, but advances to the right a bit when lights are turned on.....signals, hazards, and brakes have no affect. 

4. The flickering gauges are not a US Federalized Gwagen issue, seems to be common around the world.

5. I have noticed that most people that have posted similar issues have a 1985 or older Gwagen.  This may be a clue if no one else that has a newer model chimes in. 

6. Lastly, for now, most owners who have this problem swear that all their ground points are good and/or have recently checked/cleaned connections to insure so.

Mike 

Thanks...I can rule out #5.  It is not a pre-85 thing.  By the way, I think both signal arrows in dash are suppose to flash at same time...mine do.  If they are suppose to flash separately than that may be a vital clue.

Mike 

I did that Mark as well to no avail.  I have a new post which may provide more clues as an issue I am revisiting as well is the proper operation of the trailer/tractor indicator lamp next to difflock lamps.

Strangely, this is kind of fun.

Mike 

If I remember right, the temp sender has a single wire.  Meaning it's ground path is through the head.  Meaning that running a wire from the dashboard ground to the battery will only help the lamp in the gauge glow more consistently, not do any thing for the reading.

Try cleaning the brass of the temp sender and clipping a wire from there to battery ground and see what happens.  If it works better then you either need to pull the temp sender and clean up the threads, or add a ground wire from teh head to the battery, or solder a ground wire to the side of the sender and run THAT to ground (extreme).

One interesting thing to do if you have an accurate meter is to measure voltage above ground on various points of the daisy chain ground strap.  That strap should have four connections.  Battery post, bottom of battery tray (grounds the dog house), frame (grounds the chassis) and starter (grounds the engine).  How old is your ground braid? 

I think I mentioned before that I put a separate ground wire (full size battery cable - overkill) from the head to the battery and my temp gauge is rock solid now.  I also fixed the problem where I could make my fuel gauge jump by tapping the instrument glass when I replaced the guts with the ones from the diesel to get the glow plug light.  Rather be lucky than good!

-Dave G.

Okay..now I'm second guessing my memory.... I can't remember which of those sensors on the head were one-wire and which were two...anyway, if you find the temp sensor to be one wire (I'm 110% positive the one on the 617A is one wire), go after the grounding as stated above.

If you figure out how to make them flash separately with the single bulb that's in there, you'll really have something!

-Dave G.

Mike, all the little ground braids look like somebody trying to complete a "bonding" job to make thier short wave or CB antenna work better.  There's absolutely no reason to have a ground path from the air intake pipe or the radiator as nothing electrical is attached to either.  The use of braid instead of wire is another clue.  Braid is used to carry high frequency AC, or to bridge areas with a lot of flexing.  The radiator to the support sure isn't high flex.  So my guess is those are added afterwards by someone trying to make the vehicle a better image plane for their antenna. 

Heaven knows some of these G nuts are also radio nuts.

-Dave G.

Thanks Dave, my ground cable strap is the original with some fraying...not much though.  I will explore the temp sensor idea and try the extreme of grounded head directly.  I could swear I did this when this first reared its head.

By the way, those little braided straps are found on quite a few Gs that I have seen, including Dutch's old 'virgin' 280 ( I had to look at his photos on Pbase to confirm).  I have also seen them on photsos of Wout's pristine 280.

Mike 

Thanks, that makes some sense as well.  All the grounds in the dash ground to a common bolt.  I ran a good ground wire from battery to this ground point and did not solve problem...maybe isolation ( as you suggest)  from the "group" of wires connected to the ground point is in order.

mike 

Dave, I ran across this in the workshop manual...a braided strap to the aircleaner? I too thought, why and maybe an add on, but my air cleaner has a clean unpainted area there (which I thought was strange).  I see that as well in the workshop.

My bet is that it is part of the OPTION CODE 51 which people shows "bicycle rack" but underneath that description is an alternate decription which uses that option code as well (different years/chassis)

E51 bicycle rack, alustyle (double) (с 1978)
short-range interference suppression

Mike 

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