Earth

[TROOPER88]

Hi
I have a very detailed thread going in the Ford section as I am carrying out a full restoration on a Fiesta RS Turbo.

I am doing all of the work myself and have purchased all the relevant tools as I even sprayed it myself; totally learning as I go.

The car is nearly finished with just the engine and gearbox to go in. My question realtes to the wiring:

Every circuit has an earth strap that is screwed to the body. When securing an earth strap is it ok to screw to the metal without removing any paint?

I have heard that they must be attached to bare metal?

If that is the case do I simply use some abrasive sand paper and sand back a small area in each case?
Does it matter what screw is used; as in brass, stainless steel etc?

Thank you

[stevieturbo]

Paint is an insulator so bare metal is best.

I guess in theory a brass screw will be a better conductor, but if lug used is clean and attached to bare metal then this should be the primary conductor. Not the actual fixing.
Plus conduction through the bolt would rely on the threaded part it screws into being good clean metal etc.
Little bit of white grease or similar after to ensure it doesnt corrode after tightening.

[The Excession]

stevieturbo said:

Little bit of white grease or similar after to ensure it doesnt corrode after tightening.

Copperslip is a must for earth connections.

[phumy]

Dissimilar metal galvanic action is not your friend

[Classic Grad 98]

phumy said:

Dissimilar metal galvanic action is not your friend

My thoughts exactly, don't go buying fancy stainless or copper fixings, just use standard zinc plated fixings.

[TROOPER88]

Thank you to all who have contributed.

I will bear in mind what you say and all earth connections will be: sand area, attach with a regular screw and use some grease to prevent corrosion.

Cheers