Starter Ground Problem/Never

RoninLB · 04-17-2002, 04:34 AM

--straps that I was able to find were too small in thickness. I doubled the strap which would fit into a 1/0 ga. lug. The starter lug is 3/8in 1/0ga. The pass. side tranny mount lug is 1/2in 2/0 ga., which took 2 double straps, one double from starter and one double going to drivers side tranny mount bolt, which is 1/2in 1/0ga. The straps were soldered to lugs..The straps are safety wired to starter 2X. Stainless tab Zip connectors attach straps between starter and tranny mount. Rubber shielding is safety wired where passenger side strap passes under tranny cross member...Loctite Graphite 50 is used for corrosion protection and anti-seize. Graphite 50 is 2X as conductive as Loctite Copper anti-seize and is recommended for spark plugs on can label...Copper anti-seize is not labeled on can for spark plugs. The straps under tranny cross member are tight to cross member and may not require additional fastening...........Ron

Ronnie

RoninLB · 04-17-2002, 04:39 AM

Larger size straps than the one I used should be available from a deisel supply shop or truck/engine mfg....Ron

RoninLB · 04-17-2002, 02:16 PM

forgot to mention...the stock ground was not removed...Ron.

Doug Zielke · 04-17-2002, 03:19 PM

You're a thorough guy, Ron.

Good to see someone who understands the importance of proper grounding on these cars.

I'd say about 75% of the electrical problems experienced by owners here, are due to poor grounding and connectivity issues.

stormcrow · stormcrow's Garage

Ron,

Why did you bolt a strap between the tranny cross member? If I am looking at the pic correctly the strap goes from one tranny bolt to the other - right.

The reason I ask is that both bolts bolt to the frame and there would be no reason that I could see to place a ground strap between them unless I am missing something.

Steve

RoninLB · 04-17-2002, 07:36 PM

Steve...the 2 straps to 2 different sections of the frame is overkill....IMO, the underside is the most weathered/beaten/abused area to fasten electrical connections...OK, now it's my understanding that there is optimum areas of the body/frame to make ground attachments to prevent "ground loops". You can find them at various areas of the 911...It's my understanding that the driver's side tranny mount bolt is one of these areas..So, I had to get from the starter to the driver's side tranny mount bolt..I didn't like the strap going over the tranny..It seemed like a sloppy install with a strap maybe flapping away in the wind.. I was going past the passenger side tranny mount bolt, so WTF..The more I thought about it the cleaner the install became..For an extra $2 I have a back-up to the back-up, WTF...There are a few questions that could be answered on the install..You and Doug seem like the only two guys that are interested....this is a stimulating BB and I'm only trying to earn my keep..If you and Doug get some different ideas other than the routine stuff I didn't waste my time...Ron

Jim Sims · 08:18 PM

Looks pretty good. Did you clean any paint/corrosion off the bottom of the transmission mount bolt heads and apply silicone grease or other dielectric grease to the interface between the bottom of the bolts and the lugs and the same for the other lug/starter frame interface? Your ground path seems to be: starter frame to ground strap lug to ground strap to ground strap lug to transmission mount screw to screw threads through the Loctite graphite-50 (actually I would guess that the threads have metal to metal contact patches certain places and the current is going through those patches) to the body female thread sockets which are welded into the body sheet metal. The silicone grease and probably also the Loctite graphite-50 will keep the contact interfaces shielded from the air, water and other substances which will corrode and degrade the contact patches. Cheers, Jim

RoninLB · 04-17-2002, 08:34 PM

Jim...everything was cleaned w/600 wet/dry and alcohol..including the bolt threads and under the bolt head and mounts.. and female mount threads w/000 steel wool...I only used the Graphite 50 for everything..I think the heat and abuse under there is made for the Graphite 50..it's good enough to be recommended for spark plugs where copper anti-seize is not, according to Loctite..I'm not an expert on this, so it was a judgement call..I also believe the male/female threads of the mount will offer a more secure electrical path..I removed the stock washers and substituted a brass washer..I couldn't find copper washers..that should help the path thru the mounts, although I don't think that path is the best...Ron