mondial qv grounds

The very first place to start is at the battery. You must remove the negative ground cable and be sure that it is in good condition. Any doubt, buy a new one (at any local auto parts store). Next, you probably still have that cut-off switch between the battery cable and the chassis ground, which I had on my '84 Mondi QV. By-pass it. It's a total piece of junk. Run the new negative battery cable directly from the battery to the chassis connecting point. Be sure to clean the chassis to bare metal so that you make a very good, clean ground connection there. And be sure that you tighten the battery terminal connector down good and tight. While you are at it, clean up the positive terminal and connector, and make sure that is tight too.

After that, find the grounding strap from the engine to the chassis. It is probably the original and will look rather bad. Remove it and replace it with a brand new one from your auto parts store. When I just did my 308 ground strap, I got one 3X larger than the skinny little original one that Ferrari installed. Again, clean up the mounting locations on the engine and the chassis really well to be sure you are getting the optimum grounding.

Start with that and see if some of your electrical gremlins don't end up going away. I had a bunch of problems with my QV when I got it, and 95% of them were cured just by taking care of the things listed above.

Hope that helps!

 

I'm currently(no pun intended) re-grounding every ground that I can find on my 1980 400i with the help of Ron Francis Wiring catalogue This is not a "plug", but I think that this could help EVERY Ferrari ever built, and it's practically free . The previous poster has it bang on.

 

Ditto what Steve said above - right on. Once you've done that then you're left with looking at the various chassis grounds. There are quite a few of them. I got the car up on the lift, removed the wheel well panels and just crawled around the chassis and engine looking for every ground I could find and cleaned them all. Between this and making sure your fuse box is functional you've eliminated most sources of electrical gremlins!

 

And ditto what Cliff said about the fuse block. The one on my QV, thankfully, was in pretty good shape. But check that as well. They deteriorate pretty badly, delaminate, fry themselves, etc. There are many threads on the Mondial fuse block and development or more reliable replacements. Don't ignore yours.

 

MG, you'll find most of the grounds go to the chassis members - typically a square tube of perhaps 3/4 inches - rather than to body panels (as on most unibody cars). Trace the chasses tubes along, particularly in the area of the engine and trunk and you'll find quite a few. Also look under the dash area and footwells for a few as well.