How Many Earth's?

Hi all

I am going to attempt to fire my ABF this weekend, which has never run before, and was wired in by me, so I will have everything crossed!

Bar fitting the fuel filler neck, all I have to do is ensure the ignition and engine side of things are earthed correctly, so my question is, how many earth's and earth straps should there be?

I have an earth on the ignition loom, an earth of the wiring loom, and i will have an earth straight from the battery, but that doesn't seem enough to me.

Can anyone shed some light? Please bear in mind I am not worried about the lighting earths for now i.e. the ones that screw to the bracket on the boot floor.

Any help will be much appreciated, I would love to hear it fire at the weekend.

Thanks

David

you should have in bay:
big battery earth to gearbox and chassis leg (obviously )
main battery earth from fusebox in lighting loom
earth from ecu, where it goes depends how loom is made i run to battery -ve
earth from tci unit to battery -ve
earth from rear corner of head to one of the coil mounting bolts (mk1 dont tend to have but later cars do so worth adding one)
may or may not have a brown/white dash earth to head depending on car loom

inside:
2x earth claws above the fusebox, with various brown wires on
rear light cluster earths to the boot floor or lip depending on age

Now on the main battery earth in lighting loom, you should have a big white 4 way earth block. out the back of this is a thick brown, this goes to the claw above the fusebox. Next look at the white engine loom plug, there should be a fat brown this goes to the white earth block. Your fuel pump earth should come out of the rear loom and also plug into this earth block. any random fat browns with brown spade housings kicking about put into the let over spades on the white block, if you run out put the rest onto the claws

regarding the dash earth to the head, this is used if you have an MFA cluster. you'll find a male spade on the dash loom, on your engine loom you have a male spade brown/white that plugs in and goes to the head. non-mfa dash just earths to the claws. you can earth the mfa cluster to the claw also if its easier for you

that should cover it i recon!

rubjonny said

you should have in bay:
big battery earth to gearbox and chassis leg (obviously )
main battery earth from fusebox in lighting loom
earth from ecu, where it goes depends how loom is made i run to battery -ve
earth from tci unit to battery -ve
earth from rear corner of head to one of the coil mounting bolts (mk1 dont tend to have but later cars do so worth adding one)
may or may not have a brown/white dash earth to head depending on car loom

inside:
2x earth claws above the fusebox, with various brown wires on
rear light cluster earths to the boot floor or lip depending on age

Now on the main battery earth in lighting loom, you should have a big white 4 way earth block. out the back of this is a thick brown, this goes to the claw above the fusebox. Next look at the white engine loom plug, there should be a fat brown this goes to the white earth block. Your fuel pump earth should come out of the rear loom and also plug into this earth block. any random fat browns with brown spade housings kicking about put into the let over spades on the white block, if you run out put the rest onto the claws

regarding the dash earth to the head, this is used if you have an MFA cluster. you'll find a male spade on the dash loom, on your engine loom you have a male spade brown/white that plugs in and goes to the head. non-mfa dash just earths to the claws. you can earth the mfa cluster to the claw also if its easier for you

that should cover it i recon!

Thank you for the response, I should have guessed it would be you that responded!!

Just a couple questions you may be able to answer.

I have relocated the battery to the book, so what is the best solution to the gearbox and chassis leg earth?

Equally, the earth from the lighting loom in the bay. Where is the best place to locate this?

Thanks

David

if it was me i would run a cable from the battery to the engien bay, then terminate the engine bay wiring as per factory. i have seen people try earthing the engine to the chassis and found the starter didnt work properly any more

Thank you rubjonny