Alternator Ground Strap

[kach22i]

I'm putting my alternator back in, attaching the plastic funnel vane straighter right now.

I'm thinking that for the alternator ground strap to work, it's got to touch metal, so that means the ground strap gets sandwiched between the outer fan duct and the plastic funnel.

Does that sound right?

The other way would be to have the ground strap just bolted to the back of the plastic funnel. This is the way I remember it, but it's been a couple of days since I pulled it out and my memory is foggy.

[LakeCleElum]

I think it's bolted to the back of the plastic funnel. The ground connection is thru the stud and nut.....

[exhaustfumes]

i just did this. it is sandwiched between the plastic funnel and the fan frame.

mine fell apart from corrosion, so i replaced it with 8 gage wire with appropriate large crimp-on lugs.

[Early_S_Man]

Guys, it isn't supposed to be installed between the air deflector and alternator ... air leaks will be the result of the deflector being rased the thickness of just one terminal lug at one thru-bolt location, and that wasn't the intent of the design of the air deflector!!! Just because it CAN be installed improperly ... doesn't mean anyone else should follow the cavalier/careless instructions of those who choose to do it that way!

[kach22i]

I looked closely at the oxidization pattern of the strap, it does appear to of been between the plastic funnel and the metal duct.

Perhaps if one were to use thru bolt as a ground post it would ground okay, I'm not going to take that chance.

Thanks for the answers.

I think the strap must of been replaced at some point, it's really flexible - I thought it would be much stiffer and nastier looking.

[ianc]

There is a ground connection on the alternator itself.

ianc

[Early_S_Man]

Kach22i,

All the observed pattern you found means ... is that someone has had the alternator out during the ensuing years and reassembled it improperly a number of years ago! The air deflectors are pre-assembled to the alternator BEFORE they arrive in the production line engine area for installation!

[kach22i]

There is no way the strap is long enough to hook directly to the alternator, not on my 1977.

Anyway, I took out my meter and all my readings were up one set of lights, including the one for the battery (12 volts when off). I did not want to take any chances that the Voltage regulator was acting up on my brand new alternator and battery so I went to a shop just around the corner from my house.

A half hour and $35 later they said it all checked out, all is good. I had given them the numbers out of the 101 Projects book; 12 volts engine off, 13.5 to 14.5 volts @ 2,000 RPM, 16 to 17 Volts Bad regulator.

Read out - Print out says:

Alternator Output is within specification
diodes are good

Alternator size 60A
Maximum Current 57A
Ripple Current 14A

Idle Current 15A
Idle Voltage 13.7V

I had not driven my car since June 10th (kind of busy), six weeks I waited, just had a heck of a test drive.

[zithlord]

I just recently removed my old alternator and had it serviced. (New bearings, rings and brushes) I did the dismantling and installation my selves. I can guarantee that the alternator strap is supposed to be on the OUTSIDE of the air deflector. The ground current runs thru the bolt/nut and is connected to the engine case. It is very important to have a good connection or else a lot of strange things can happen to all electrical systems in the car. On my car (73 911S) I was surprised at how short the ground strap was and it was very difficult to both remove the alternator assembly and fan house because of the short strap(it was the original strap) I had to twist and turn the fan house, putting it back was a bit easier but I had to put the nut on the bolt with the ground strap on “blind” with my hand crammed in behind the fan house.

[Gasman59]

Having removed and installed my alternator 3 times (Don't ask, subject of an earlier post and why NOT to use a local shop).

The strap is attached to the outside of the air deflector.

Make sure you clean up the strap end.
I also used a locking washer, the finned type, not split, to improve the connection, between the strap and nylock nut.

The mounting nuts are self locking and if you haven't yet, purchase and use new ones.

Best Wishes,
Ron
1970 911 E Targa

[kach22i]

Now I remember the sprial locking washer and strap were on the bolt side, still I'm getting a good ground so there ya go.

Your mission should you decide to accept it..................



Good time to clean, found the new "Gel: cleaner by Gunk to work much better than the old foam type cleaners. Of course those tiny metal brushes that look like big tooth brushes come in very handy.



Leave time to polish and paint while you are in there, good thing I had some high temp black paint lying around, and some metalic silver paint for the strap.

[kach22i]

By far the coolest part of the whole assembly is the back cone.

[RoninLB]

fwiw..

just to add some bs. The alternator ground should technically be grounded at the battery. If you can't use the strap use 8ga wire imo.

[cbeers]

Just installed mine last night and the ground is an Ian stated, directly to the alternator. maybe it's a Carrera thing. I took many digital pics during the removal process to be sure I got it back correctly.

I'll post another thread with pics tomorrow or so....

Just my $0.02


-Chris

[ianc]

Yes, my ground strap was perhaps a foot to a foot and a half long. It goes in through the hole in the air deflector and connects to one of the side connectors on the altenator. To the left of B+ IIRC. At least that's the way it was put together on mine. Who knows if that's factory...

ianc

Edited to say: Mine's the Paris Rhone alt...

[kach22i]

I should note that the lable ID's of "A, B and C" on my drawing were my own lables to match what I wrote on masking tape and not actual labling found on the back of the alternator.

[Gasman59]

Coffee!! I was expecting to see a few beers by now.

[kach22i]

Originally posted by Gasman59
Coffee!! I was expecting to see a few beers by now.

It was a several day event for me, had to pace myself.