Register now to get rid of these ads!

Customs BAD GROUND!

Discussion in 'The Hokey Ass Message Board' started by flynbrian48, Jan 8, 2020.

  1. flynbrian48
    Joined: Mar 10, 2008
    Posts: 8,220

    flynbrian48
    Member

    I spent the last four 81567255_10221901672993600_5703229640055717888_o.jpg 81503883_10221969388686450_9152272091674836992_n.jpg days (well not all day, but enough to get frustrated 4 days in a row) trying to figure out why the power window in my '63 Rivi project suddenly quit working in the passenger door. I had juice to the switch, tried to take it apart to clean the contacts, it broke. Bought a new (to me) one, still didn't work. Finally occurred to me that, after much head scratching, that the door itself wasn't grounded to the body.

    I'd replace the motor because it was seized, worked fine after that. Then, I'd discovered that all but two of the eight door hinge mount bolts had been broken off. I drilled the bolts out of the cowl, tapped and replaced 'em all, and liberally lubed, WD40'd everything.

    Ah-HA! Why it didn't ground through latch is a mystery, but it didn't. After I figured out what the deal was, rather than take the door back off to clean and de-grease every bolt hole (it's a bitch to align these HEAVY doors), I ran a ground wire from the door skin to the cowl.

    What a pain, but a good example of how a poor ground can make the simplest thing seem complicated.
     
  2. Wanderlust
    Joined: Oct 27, 2019
    Posts: 787

    Wanderlust

    Can never have too many grounds, especially not with older vehicles
     
  3. flynbrian48
    Joined: Mar 10, 2008
    Posts: 8,220

    flynbrian48
    Member

    LOL, turns out, there's a 1965 Buick Service Bulletin for this exact problem the fix is exactly what I did! Run a ground strap from door skin to cowl...
     
    loudbang, bchctybob, Petejoe and 2 others like this.
  4. Brian, I have numerous problems on late model shit that have come down to bad grounds. Now the first thing I check is the grounds on EVERTHING. Mitch.
     

  5. alchemy
    Joined: Sep 27, 2002
    Posts: 20,405

    alchemy
    Member

    Keep your feet on the ground, and keep reaching for the sparks!
     
  6. Mr48chev
    Joined: Dec 28, 2007
    Posts: 33,861

    Mr48chev
    ALLIANCE MEMBER

    All of the grease and thread lube probably served as an insulator.
    I have no idea of how many cars I have been asked to look at that the owner had fought for hours to days and longer with electrical issues that were ground issues. One replaced his battery, alternator and starter fighting the issue that ended up being a loose ground cable from battery to block. Another had so many coats of engine paint on the engine that there was no way it would ground and cried when I took my knife and scraped the spot below the ground strap down to bare shiny metal to get a good ground. Blew his mind when he engine cranked right over though.
    Back in the 70's and 80's I replaced a lot of Pontiac floor shift cables on cars that someone had had the valve covers off and didn't put the ground straps from the firewall to the valve cover bolt back on. The cable acted as the ground for the body and the cable welded it's self to the inside of the housing.
     
  7. Good grounds are your friends.:D
     
  8. flynbrian48
    Joined: Mar 10, 2008
    Posts: 8,220

    flynbrian48
    Member

    Part of the problem is that I've been working on this thing so sporadicly that I forget what I've done. It didn't occur to me that the window motor worked fine until several months ago when I aligned the door gaps, and found to my great surprise the passenger door had only two bolts left at the hinge plates (no wonder it sagged when opened). The thing I'd done before that was to replace that window motor, align the tracks and glass, it worked great. Then I fixed the door and haven't touched the car until the other day, when doing something else, I tried to lower the glass and nothing happened (I think I was trying to get at the new air conditioner unit I'd run a sheet metal screw into the copper heater core tube inside the plastic housing through the firewall on, but that's another story). It's a good thing I find this stuff fun, or I'd just go buy a new Camaro or Challenger...
     
    loudbang, pitman, williebill and 3 others like this.
  9. Bert Kollar
    Joined: Jan 10, 2007
    Posts: 1,232

    Bert Kollar
    Member

    Years ago I built a fiberglass car and had a ground fault. If you want to see weird things happen when you loose a ground build one of those. Since then I ground EVERYTHING and test it. I had a problem with a brand new fuel sending unit that had a loose rivet and intermittent ground problem. I run several ground wires especially if the parts are separated eg firewall , frame, fuel tank, gauge panel. Don't assume the bolts will continue the ground.
     
    loudbang and flynbrian48 like this.
  10.  
    loudbang and flynbrian48 like this.
  11. Boneyard51
    Joined: Dec 10, 2017
    Posts: 6,440

    Boneyard51
    Member

    Way back in the early seventies, at my first job as a mechanic, I drew a job on a truck that had no tail lights. I grabbed my trusty test light and went at it! Well, it was acting funny, then I touched my grounded test light to the tail light housing and my light came on! Really! Ground to ground and it lights up! I thought I was in the twilight zone! I showed one of the older mechanics thinking I has just discovered something unworldly. He calmly said” check your grounds , kid” I did, found a bad ground, fixed it , everything went to working perfectly!

    I never forgot that lesson ! When something seems strange, acting weird , it’s usually a ground. Bad grounds are a high percentage of electrical problems. I was always adding ground wires on my Firetrucks. Like mentioned, you can never have too many.






    Bones
     
    loudbang, pitman, williebill and 3 others like this.
  12. BrerHair
    Joined: Jan 30, 2007
    Posts: 5,006

    BrerHair
    ALLIANCE MEMBER

    Verrrry interesting.....
    It never ceases to amaze me how much work goes into these builds/resto’s
    Well done sir!
     
    loudbang and flynbrian48 like this.
  13. ekimneirbo
    Joined: Apr 29, 2017
    Posts: 4,216

    ekimneirbo

    Since you have to have a hot wire running to the window motor, put another wire right next to it . Attach one end to the motor and the other end under your dash . Do it on both doors. Then check or install a ground from the firewall to the cars engine. Personally I don't think a ground from the door to the body does much more than insure a future problem.;)
     
  14. flynbrian48
    Joined: Mar 10, 2008
    Posts: 8,220

    flynbrian48
    Member

    The engine is grounded to the cowl with the original Buick straps. I'm gonna use a couple more ground straps to the chassis (after I get the thing de-scaled) and body at the front and the rear, after this fiasco. I want to ensure good grounding, there's nothing that confuses an engine control module more than poor ground.
     
    loudbang and Boneyard51 like this.
  15. flynbrian48
    Joined: Mar 10, 2008
    Posts: 8,220

    flynbrian48
    Member

    When I put the A/C unit back under the dash yesterday, I noticed, looking at it through the firewall on the engine side, that there was a frayed wire peeking out of the (wrapped) wiring harness in the unit. What the....? Turns out, I also managed to run a sheet metal screw INTO THE WIRING HARNESS THAT SEVERED 3 OF THE 8 WIRES FOR THE CONTROLS! So, out it came again, fixed that and got it back in. If I'd have wanted to do that, measured carefully, I'd never have been able to hit either one of those by driving a self tapping sheet metal screw blindly into them.
     
    loudbang and Boneyard51 like this.
  16. LOL! Murphy's Law.

    Ben
     
    loudbang and Boneyard51 like this.
  17. Jmountainjr
    Joined: Dec 29, 2006
    Posts: 1,672

    Jmountainjr
    ALLIANCE MEMBER

    While you have the door opened up you might consider getting rid of those non-sealed butt connectors. They look like a future problem in that potentially damp environment.
     
  18. Speaking of grounds, is Dialectic grease a conductor? I heard somewhere that it wasn't, and was planning on coating my ground points with it to prevent corrosion...
     
    loudbang likes this.
  19. Moriarity
    Joined: Apr 11, 2001
    Posts: 30,775

    Moriarity
    SUPER MODERATOR
    Staff Member

    I couldn't help but notice that you are writing notes on your car with magic marker. I did the same thing when I was working on restoring the Car Craft dream rod. I stripped it to bare metal and when I sprayed my first coat of etch primer on it all of the magic marker writing appeared thru the primer (yes i washed it off with lacquer thinner). I had to stop and wash the primer off and grind the metal everywhere I had written on it. Now if I have to write on a car I put making tape on it and write in pencil.....
     
  20. Gearhead Graphics
    Joined: Oct 4, 2008
    Posts: 3,890

    Gearhead Graphics
    Member
    from Denver Co

    Argh grounds!
    I had a harley that would die intermittently, like going down the interstate in traffic! Sometimes it would sit all day, sometimes it would fire back up before you made it to a stop on the shoulder.

    I traced it down to a bad ground, couldn't find WHERE the bad ground was, So I made 2 new ground wires, front half and back half were then grounded well. It ran great for about 6 months and started up again. Traded that bike off and never missed it!
     
    flynbrian48, loudbang and Boneyard51 like this.
  21. That is one lesson you retain. I was lucky to have made that revelation many moons ago. I have a few ground straps made up (also doubled as roach clips back in the day...) that are coiled up in my top box. For putting doors back on, if you have access through the inner skin into the hinges, drill a couple of 3/16" holes through the skin and hinge. I line them back up with drill blanks or transfer punches. Make a 2 hour job into a 10 minute job.
     
    loudbang and Boneyard51 like this.
  22. Boneyard51
    Joined: Dec 10, 2017
    Posts: 6,440

    Boneyard51
    Member

    Get you some “ Corrosion Block” It will amaze you! My friend turned me on to this and it works! He has solved many electric problems with it! I have a couple under my belt already!








    Bones
     
    loudbang likes this.
  23. Boneyard51
    Joined: Dec 10, 2017
    Posts: 6,440

    Boneyard51
    Member

    My friend bought a Harley Tour glide new about 2010. Always had some odd things about it, pop every once in a while, run good run bad, took it back to two dealers, did a recall . Things helped but never fixed it. This went on for two years! He got out some where and it would only start if you pulled in the clutch. He stopped at a old bike shop and told his problem to an old biker mechanic. The old guy said he knew what it was pulled off his negative battery cable and it had a “ bad” crimp on it where it bolted to the frame! He recrimped it, put it on, my friends bike ran perfect after that! He blamed it on Harley and probably rightfully so but the problem was a BAD GROUND!








    Bones
     
    loudbang and Truckdoctor Andy like this.
  24. error404
    Joined: Dec 11, 2012
    Posts: 383

    error404
    Member
    from CA

    When ever I can, I run a ground wire from all electrical devices to a common ground stud that has a cable going directly to the battery or starter motor, rather than self-tapping a screw into body/frame metal near by. Sometimes multiple ground studs, one in front one in rear. Or sometimes a "ground bus bar" on the fuse box.

    I've had too many ground problems in the past, this seems to avoid most problems. It does use more wire though.
     
    Last edited: Jan 10, 2020
    loudbang likes this.
  25. Boneyard51
    Joined: Dec 10, 2017
    Posts: 6,440

    Boneyard51
    Member

    Many troubles in vehicles are a result of bad grounds. As stated, the battery has a huge ground cable going to the engine block to supply the starter with 100% of battery power. Then small wires are “ SUPPOSED” to go from the engine to the body and also to the frame, did I say “ supposed” to? On my vehicles I add a larger additional ground to the body and frame. I always use the frame for the main ground bus! I do this so that I can grab a ground anywhere the length of the vehicle. And the frame is capable of carrying the current any battery is capable of putting out!






    Bones
     
    Last edited: Jan 10, 2020
    INVISIBLEKID, Wanderlust and loudbang like this.
  26. David Gersic
    Joined: Feb 15, 2015
    Posts: 2,730

    David Gersic
    Member
    from DeKalb, IL

    Dialectic grease is an insulator. It blocks corrosion from the air, which is good. You can use something like a star washer on it, though.



    Sent from my iPad using The H.A.M.B. mobile app
     
  27. 6sally6
    Joined: Feb 16, 2014
    Posts: 2,459

    6sally6
    Member

    Not totally off topic but still relevant (I THINK!)o_O
    My off topic parts gitter developed a sporadic 'miss.................just like the time when the in tank fuel pump started going bad a few years back. I figgered...."I got 'cha this time!!! I KNOW whats worng"
    Got my pal to help me REMOVE the bed (after we dropped the 28 year old...never been on the ground spare tire!) One of us underneath and the other up top and handing tools we got it out and replaced and finally ALL put back together. Went for a test drive and still doing the same skipping mess! grrr!
    Popped the hood to take a look at the injectors while the engine idled. That's when I saw the spark plug wire arcing off the exhaust manifold!!!!!!!! New plugs and wires (AND NEW ELECTRIC FUEL PUMP!!!) and all was well.
    GREAT way to spend a half day and a hundurd bux!
    Always check the simple stuff first.............like bad(or non-existent) grounds!
    6sally6
     
    Boneyard51 likes this.
  28. donno
    Joined: Feb 28, 2015
    Posts: 426

    donno
    Member

    I found a couple of 70-80 series El Caminos that had aluminum rivets holding the power window motors in, aluminum don't ground for shit.
     
    Boneyard51 likes this.
  29. flynbrian48
    Joined: Mar 10, 2008
    Posts: 8,220

    flynbrian48
    Member

    Good advice. Of course, all that old paint is coming off. Assuming of course I can get this thing running...
     
  30. Beanscoot
    Joined: May 14, 2008
    Posts: 3,053

    Beanscoot
    Member

    Dielectric grease, and other greases are indeed insulators but you'll notice late model stuff has this grease on the connector plugs. The grease keeps out water and corrosion, and the metal still touches metal.

    I use dielectric grease or regular grease or oil, whatever is handy, when I put any ground connection (or pretty well any fastener) together. The main purpose is to keep out the non-conductive corrosion that will otherwise occur.
     

Share This Page

Register now to get rid of these ads!

Archive

Copyright © 1995-2021 The Jalopy Journal: Steal our stuff, we'll kick your teeth in. Terms of Service. Privacy Policy.

Atomic Industry
Forum software by XenForo™ ©2010-2014 XenForo Ltd.