Rectifier negative post keeps breaking - Suggestions needed

[tim m]

The rectifier has a insulator keeping it from contacting no smiles just good business

[Tikka]

use the same type of connection , the car engine is connected chassis

[Ostinato]

Unfortunately the rectifier is completely isolated from the alternator body so that suggestion will not work.

[unclemack]

Originally Posted by Ostinato

Unfortunately the rectifier is completely isolated from the alternator body so that suggestion will not work.

I'd have been more than a bit surprised if it wasn't an insulated return

There's nothing wrong with mounting an insulated bus bar on the alternator or on the engine for all the earths (sorry, negatives) as some suggested.

I had a truck years ago with an extra steel bracket fixed to the rear lower alternator mounting for the same reason. 5mm plate and a hole with a rubber grommet for the cable. That'd work too.

Any of the suggestions that shift the vibration to somewhere else and maintain the insulation will work just fine. I'd have used a cable tie but then I'm very, very lazy...

[Ostinato]

Hmm - I'd have to think about how to mount a bar like that but the idea has possibilities. I tried the cable tie this last time and it obviously didn't work.

Does anyone whether an engine vibrates side to side mainly or is it all over the place? If it is side to side that might let me install the neg wire so that ii is perpendicular to the alternator - in other words in line with the vibrations.

[twinboat]

They bounce all over the place. Stick a stiff wire on it, sticking up, and watch the harmonics various RPMs.

The power post with a short jumper is the best cure.

You may be able to use a copper link to ground the diode post to the case and then move the cables to the case, if you don't need the isolated ground. Most engine blocks are grounded anyway.

[Ostinato]

Ok - so here what I have done since I am in Sicily and materials and a machine shop are not immediately available. I had enough wire to reroute the neg house bank wire so that I could bundled it with other wire and tubing connected to the engine. This bundle attaches to the engine just to the left of the fresh water pump and above and the right of the Balmar. The vertical strain of the negative lug should be minimal at the point and hopefully the whole rig will vibrate (dance) as one with most of the vibration being adsorbed by the wire bundle as crosses over to a bulk head. I will have to inspect for chafe and other signs wear but I think it is better than what I had. I'll keep the old rectifier in case this one goes but i will have to hook it up with a common ground to the engine if I use it.

Thanks everyone.