Announcement

Collapse
No announcement yet.

Wiring up the negative side of the battery -

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Wiring up the negative side of the battery -

    The Imp has always had a weak spot as far as i am concerned which is the method by which the high current path gets connected to the engine.

    Default is a piece of braided strap at the transaxle mount which has been under their for years and likely the terminals have been flattened/beat to heck.

    Click image for larger version

Name:	PIC-00092.jpg
Views:	113
Size:	293.0 KB
ID:	5457

    End result is folks can be seen to add "ground" wires from the battery to the engine block to chase down ignition problems.

    However when the actual "connection" goes faulty your high current path for the starter what happens to the little wire you added for thos "ignition issues" yip meltdown and fire !

    Click image for larger version

Name:	PIC-00093.jpg
Views:	98
Size:	33.5 KB
ID:	5456

    Lovely eh ??

    My own solution is to make th high current path for the starter (and ignition) seperate from the car and double up everything.

    Original Imp battery terminal wire is 16mm sq at best and chances are VERY old so not as good as wehn new.

    So time to make some new ones, this time 25mm sq braid and crimped on terminals between the battery and engine direct.

    First the one for the engine direct

    Click image for larger version

Name:	20200326_132606.jpg
Views:	77
Size:	166.8 KB
ID:	5458

    And then installed as you can see, between battery and block.

    DO NOT USE THE TRANSOM !!! as an intermediate connection.


    Click image for larger version

Name:	20200326_135959.jpg
Views:	72
Size:	414.2 KB
ID:	5460
    Click image for larger version

Name:	20200326_141531.jpg
Views:	67
Size:	343.6 KB
ID:	5461Click image for larger version

Name:	20200326_142242.jpg
Views:	64
Size:	352.1 KB
ID:	5459

    And then an extra two leads,

    One 25mm sq lead from the battery terminal to the chassis leg
    Second 16mm lead from battery terminal to the inner wing (factory point)

    Lead specifications I used

    Lead 1 - Battery Terminal to Engine Block

    25mm sq tinned copper braid - 500mm long
    25-8 crimp terminals - 2 of these, the part number measn 25mm sq cable and 8mm hole
    Crimped both ends, lubbed up to be water resistant and then covered in heat shrink sleeve

    Lead 2 - Battery terminal to Chassis leg

    25mm sq copper cable PVC insulated - 380mm long
    25-8 crimp terminals - 2 of these, the part number measn 25mm sq cable and 8mm hole
    Crimped both ends and both end witha little lube then covered in heat shrink sleeve

    Lead 3 - Battery Terminal to Inner Wing (Factory point)

    16mm sq copper cable PVC insulated - 180mm long

    16-8 crimp terminal - 1 of these, the part number measn 16mm sq cable and 8mm hole
    - Attached to the chassis leg with a 5/16 bolt, i opened up an existing hole and installed a Rivnut

    16-6 crimp terminal - 1 of these, the part number means 16mm sq cable and 6mm hole
    - Attached to the inner wing using a 3/8" bolt same as factory

    Crimped both ends and both end with a little lube then covered in heat shrink sleeve

    Click image for larger version

Name:	20200326_161600.jpg
Views:	63
Size:	187.3 KB
ID:	5465Click image for larger version

Name:	20200326_144353.jpg
Views:	63
Size:	343.0 KB
ID:	5464
    Click image for larger version

Name:	20200326_161556.jpg
Views:	63
Size:	221.4 KB
ID:	5463Click image for larger version

Name:	20200326_161609.jpg
Views:	63
Size:	175.2 KB
ID:	5462

    Deed done

    These leads can be procured online from the shelf or custom made.











    / John

    If it can be fixed with a hammer, I am your man

  • #2
    Why no use the transom panel

    Comment


    • #3
      Originally posted by Dave Lane View Post
      Why no use the transom panel
      Dave

      Relies on bare metal/metal on the 6 attachment points and to leave bear metal there just rots it away.

      Other than that why go from battery to chassis or transom panel then transom to engine block when you can just go direct

      Have seen same problem when transom attach points get poorly or of course when folks do not put all the bolts back in and rely on the two nuts and bumper bolts ! same result, low current paths to engine gets the stress.

      Have seen 0.4V drop going through attach points of transom to engine, using the little link from engine mount to block . That is meter on engine block or batt terminal, staretd fine but dissapointing given the braid at transaxle and the other path via transom. Yet loss via chassis to front of car was almost the same.

      Best path is always direct betwen the 2 points


      / John

      If it can be fixed with a hammer, I am your man

      Comment


      • #4
        Originally posted by John A. Ross View Post

        Dave

        Relies on bare metal/metal on the 6 attachment points and to leave bear metal there just rots it away.

        Other than that why go from battery to chassis or transom panel then transom to engine block when you can just go direct

        Have seen same problem when transom attach points get poorly or of course when folks do not put all the bolts back in and rely on the two nuts and bumper bolts ! same result, low current paths to engine gets the stress.

        Have seen 0.4V drop going through attach points of transom to engine, using the little link from engine mount to block . That is meter on engine block or batt terminal, staretd fine but dissapointing given the braid at transaxle and the other path via transom. Yet loss via chassis to front of car was almost the same.

        Best path is always direct betwen the 2 points

        OK , Ive got a transom one but theres also an earth lead from transom mount to inner wing , might go your route in that case

        Comment


        • #5
          Dave, just measure, one lead on batt +VE, other on engine block take note, one on battery take note, then do same on crank.

          If all is good leave it as it is. I am just paranoid
          / John

          If it can be fixed with a hammer, I am your man

          Comment

          Working...
          X