Earthing GRP tank in GRP boat?

Discussion in 'Fiberglass and Composite Boat Building' started by richofoz, Jan 11, 2013.

  1. richofoz
    Joined: Jul 2010
    Posts: 12
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Melbourne

    richofoz Junior Member

    Hi guys, just wondering how you all would earth/ground a glass tank in a glass boat?
    Can I just run a wire from the filler to a negative on a battery?

    Thanks for any advice.

    Rich.
     
  2. gonzo
    Joined: Aug 2002
    Posts: 15,617
    Likes: 1,107, Points: 123, Legacy Rep: 2031
    Location: Milwaukee, WI

    gonzo Senior Member

    You can't. GRP is not a conductor, therefore a wire won't make any difference.
     
  3. jonr
    Joined: Sep 2008
    Posts: 721
    Likes: 11, Points: 0, Legacy Rep: 57
    Location: Great Lakes

    jonr Senior Member

    Use a layer of carbon fiber?
     
  4. richofoz
    Joined: Jul 2010
    Posts: 12
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Melbourne

    richofoz Junior Member

    I hope you're right gonzo!
    I have however, cleaned and waxed plenty of moulds before and have received some pretty serious static shocks!

    I know the tanks not going to get rubbed by anything to create static.

    It's just when I put the static build up i had seen on moulds together with a petrol tank the idea concerned me and I certainly don't want to learn the hard way in his situation!

    Rich.
     
  5. whitepointer23

    whitepointer23 Previous Member

    rich, i had a savage lancer with twin 200 lt glass petrol tanks, i only remember earth wires on the metal filler necks.
     
  6. CDK
    Joined: Aug 2007
    Posts: 3,324
    Likes: 148, Points: 63, Legacy Rep: 1819
    Location: Adriatic sea

    CDK retired engineer

    Just a wire from the filler neck to the DC negative to prevent sparking.
    It is mandatory in a lot of countries.
     
  7. gonzo
    Joined: Aug 2002
    Posts: 15,617
    Likes: 1,107, Points: 123, Legacy Rep: 2031
    Location: Milwaukee, WI

    gonzo Senior Member

    That wire is not required with plastic filer necks.
     
  8. SamSam
    Joined: Feb 2005
    Posts: 3,900
    Likes: 198, Points: 63, Legacy Rep: 971
    Location: Coastal Georgia

    SamSam Senior Member

    If it was built in , wouldn't it be grounded sitting in the water? On a trailer at the gas station would be a different situation.
     
  9. richofoz
    Joined: Jul 2010
    Posts: 12
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Melbourne

    richofoz Junior Member

    Sam Sam I do follow your logic, but experience suggests something may be up!

    I do run a stainless filler neck in my tank, would a plastic fitting guarantee no static sparks? Not sure what the difference is when static is concerned?

    CDK that is what I was planning to do...
    Is there any evidence that it (A) does what I want it to do and (B) is this evidence that the problem I'm trying to fix exists?

    I will admit that as soon as it leaves the realms of normal 12v wiring I'm not the best person to ask but...
    If static were to build up on my tank could it be "dissipated" via a wire to a nrgative on a battery or something similar

    I am going to run a wire from the stainless filler to a - terminal on the battery.
    It might do nothing or it might prevent a spark from the cap to the tank!
    Who knows what a spark might do in the vicinity of fuel vapours and some nice fresh air!

    Hopefully it will just be a waste of wire!

    Thanks for the replies!

    Rich
     
  10. Ike
    Joined: Apr 2006
    Posts: 2,544
    Likes: 381, Points: 83, Legacy Rep: 1669
    Location: Washington

    Ike Senior Member

    Static can build up on a fuel hose, plastic fill tube, or a tank when filling the tank. The fluid running through the fill creates it. But a simple wire from the metal fill fitting to the tank gauge fitting and then to the boats' ground will dissipate the static. This includes GRP tanks. As long as the metal fittings are grounded you will not have a static discharge.
     
  11. michael pierzga
    Joined: Dec 2008
    Posts: 4,862
    Likes: 115, Points: 0, Legacy Rep: 1180
    Location: spain

    michael pierzga Senior Member

    The plastic gas tank installations I see have both the tank grounded and the fuel fill , vent fitting grounded.

    If you google USCG or the various tank manufactures websites for installation instructions , you will see logical schematics of approved tank installations.

    Ive always understood that "ground" or earth on a small plastic outboard boat is the stainless steel thru bolt that holds the motor clamp to the transom.

    The electrical system Negative may or may not be a ground and may not even exisit on a small outboard boat.
     
  12. gonzo
    Joined: Aug 2002
    Posts: 15,617
    Likes: 1,107, Points: 123, Legacy Rep: 2031
    Location: Milwaukee, WI

    gonzo Senior Member

  13. michael pierzga
    Joined: Dec 2008
    Posts: 4,862
    Likes: 115, Points: 0, Legacy Rep: 1180
    Location: spain

    michael pierzga Senior Member

    Plastic fills. no ground needed.
     
  14. Ike
    Joined: Apr 2006
    Posts: 2,544
    Likes: 381, Points: 83, Legacy Rep: 1669
    Location: Washington

    Ike Senior Member

    Plastic fills do not need a ground, especially on trailerable boats.

    From the USCG back in 2005 or 2006 (memory fading fast! LOL)
     

  15. Ike
    Joined: Apr 2006
    Posts: 2,544
    Likes: 381, Points: 83, Legacy Rep: 1669
    Location: Washington

    Ike Senior Member

    Here's a link to some basic fuel tank installations. The first is for gasoline tanks installed after January 1, 2o12, to meet US EPA environmental standards. The second is what was required prior to January 1, 2012

    http://newboatbuilders.com/pages/fuel_tank.html
     
Loading...
Similar Threads
  1. Jaco
    Replies:
    1
    Views:
    335
  2. Martin Upton
    Replies:
    44
    Views:
    3,910
  3. Martin Upton
    Replies:
    63
    Views:
    4,020
  4. PitMan
    Replies:
    16
    Views:
    1,147
  5. Miscbrah
    Replies:
    7
    Views:
    1,563
  6. mtumut
    Replies:
    4
    Views:
    1,486
  7. dbsharples
    Replies:
    15
    Views:
    5,207
  8. JimmyR
    Replies:
    3
    Views:
    1,662
  9. shepted
    Replies:
    5
    Views:
    1,638
  10. Rupes
    Replies:
    11
    Views:
    3,597
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.