Wiring up the negative side of the battery -

[John A. Ross]

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.



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 !



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



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

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





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




Deed done

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

[Dave Lane]

Why no use the transom panel

[John A. Ross]

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

[Dave Lane]

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

[John A. Ross]

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