Earthing Through Battery Tray

[pete1986 2]

Whilst my engine was out a couple of months ago i decided to give it a bit of a respray, but totally forgot about the ignition amp earthing through the battery tray . The problem was solved by moving it to the earthing points by the expansion tank. However, i have now put a diesel battery in to help with cold cranking and its a bit of a stretch for the wires to reach around it.

 

So now im going to have to mount it back on the battery tray, thus meaning i need to take the tray off and remove the paint between it and the chassis. My question is, how can i protect the bare metal from rust whilst still getting a good earth? When i took the tray off in the first place i remember it had bluey-silver paint where the two surfaces met...

 

Cheers

Pete

Edited February 3, 2009 by pete1986

[Anthony 1,000]

Should earth OK through the bolts alone IMO so long as you clean off the paint behind where the bolt head sits.

 

That said, the ignition amp shouldn't need to be earthed through it's body in my experience, so long as the appropriate pin(s) on the connector are earthed - certainly I've left them sitting loose in the engine bay whilst fault finding and they've worked fine. Probably best it's bolted to something for heat disipation (the metal plate is there as a heatsink) and the wiring can earth elsewhere.

[maxi 36 1 Cars]

Should earth OK through the bolts alone IMO so long as you clean off the paint behind where the bolt head sits.

 

That said, the ignition amp shouldn't need to be earthed through it's body in my experience, so long as the appropriate pin(s) on the connector are earthed - certainly I've left them sitting loose in the engine bay whilst fault finding and they've worked fine. Probably best it's bolted to something for heat disipation (the metal plate is there as a heatsink) and the wiring can earth elsewhere.

 

 

Completely agree with Ant here Pete........ If you are at all worried I wouldnt remove any paint from the battery train mounting points. All I would personally do is run an extra earth strap from an earthing point on the actual car body to the tray. What loom is it your using again? The BX loom should have more than enough length to get you over to the main car body anyway if you want to mount your ignition module there?

 

Maxi

[pete1986 2]

Completely agree with Ant here Pete........ If you are at all worried I wouldnt remove any paint from the battery train mounting points. All I would personally do is run an extra earth strap from an earthing point on the actual car body to the tray. What loom is it your using again? The BX loom should have more than enough length to get you over to the main car body anyway if you want to mount your ignition module there?

 

Maxi

 

I'm using Dan's old loom, from a late BX iirc. Its too tight with ign amp on the said earthing points with the diesel battery there. Ill have to have a better look, perhaps i could try re-routing it.

 

I had solved the slow cranking with the diesel battery, then it wasnt sparking because of the ign amp. One thing after another.

 

Anyway, I'll try mounting it back on the tray, then run an earth strap from the underneath of the tray (on the same bolt as ign. amp) to the bumper bracket on the inner wing. I'll report back once iv done that, may not be until the weekend when i have some spare time.