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You could use a regular bolt to hold down the connectors, with an inside- or outside- star washer; the tapped threads are plenty strong enough.
If you want to make a stud for some reason you could tap the hole then put a nut on the -outside- to lock it. I wouldn't otherwise drill a structural member, and Tesla would disqualify you if you ever want recert.
If you want to make a stud for some reason you could tap the hole then put a nut on the -outside- to lock it. I wouldn't otherwise drill a structural member, and Tesla would disqualify you if you ever want recert.
quickstrike12
Member
Has this issue been corrected from the factory at some point along the way? In other words is there an earlier year models that seem to show this issue?
If you relocate the bolt, it should go into a rivnut (rivet nut). This kit from amazon includes both the tool and some rivnuts. And slather everything in dielectric grease.
Astro Pneumatic Tool 1442 13" Hand Rivet Nut Setter Kit - Metric & SAE W/ 60pc Rivnuts
Astro Pneumatic Tool 1442 13" Hand Rivet Nut Setter Kit - Metric & SAE W/ 60pc Rivnuts
aerodyne
2 of 3 EV's - Defect Free!
Compared to the JDM cars I have owned, looking under the Frunk I see a complete lack of design features for corrosion prevention, starting with drain holes in the needed places.
Someone asked, what do aircraft do? Quite simple, aircraft bolts in aluminum are plated with Cadmium, which is corrosion inhibiting and a good galvanic match with aluminum. Ground connections in aircraft have the paint removed under where the bolt head contacts the structure, check for resistance less than 1 ohm, then over coat with polysulfide sealant.
In this case I will bet the threads do not match common aircraft bolts (AN or NAS or MS series) with the cad plate.
I would use any stainless bolt of the same thread, clean the hole and threads and lugs with a brass or plastic brush, and then install with a torque suitable for those theads on alum. Brush clear grease over the joint, sealant that is not acid curing (non silicone) is ok too.
Someone asked, what do aircraft do? Quite simple, aircraft bolts in aluminum are plated with Cadmium, which is corrosion inhibiting and a good galvanic match with aluminum. Ground connections in aircraft have the paint removed under where the bolt head contacts the structure, check for resistance less than 1 ohm, then over coat with polysulfide sealant.
In this case I will bet the threads do not match common aircraft bolts (AN or NAS or MS series) with the cad plate.
I would use any stainless bolt of the same thread, clean the hole and threads and lugs with a brass or plastic brush, and then install with a torque suitable for those theads on alum. Brush clear grease over the joint, sealant that is not acid curing (non silicone) is ok too.
Cadmium is toxic and I suspect that use in aircraft is an exception. Stainless bolt is a good suggestion. Threading depends on what you tap it as; the rest of the car is metric, reasonably.
There are lots of fake RTVs, but for 50 years I've used Permatex brand; it's the real deal.
What he means by this is normal silicone caulk cures by offgassing acetic acid. (the vinegar-smell of caulk) This can corrode electrical connections. For this you'd use RTV silicone ('Room-Temperature Vulcanizing') which has a more neutral catalyst, although trying to caulk something like this is counterproductive as water will usually find a way in (from the back? Condendate?), and caulk will actually retain it.
There are lots of fake RTVs, but for 50 years I've used Permatex brand; it's the real deal.
aerodyne
2 of 3 EV's - Defect Free!
aerodyne
2 of 3 EV's - Defect Free!
Cad is toxic if you weld it, which is bad for the weld too. Aircraft bolts will net be toxic if you use normal precautions in handling
True, cadmium electroplating isn't so bad, but they probably wouldn't want to use them in a mass-market product. And hopefully you've been wearing gloves.
Anytime I have to solder wires in the car (inside or outside) I first put on heatshrink, solder, then RTV everything. And heat the heat-shrink until RTV squeezes out the ends. Yeah I use matches which isn't good; should pull out the paint-stripping heat gun but I never do.
Anytime I have to solder wires in the car (inside or outside) I first put on heatshrink, solder, then RTV everything. And heat the heat-shrink until RTV squeezes out the ends. Yeah I use matches which isn't good; should pull out the paint-stripping heat gun but I never do.
Didn't VW just have to perform a recall on their cars because the charger contained a very small amount of cadmium? (Yep they did.)
I don't think you are allowed to use cadmium in a car...
robby
Member
Thanks to everyone for the help and advice.
I tapped a 3/8"-16 hole in the (bronzed, I think?) piece on the chassis, and went bolt > 3 washers > wires > 3 washers > double nut > star locking washer > chassis. (I needed washers to fill some non-threaded space on the bolt). I applied dielectric grease around all layers, and I used stainless steel for everything, which should fare much better against salt than the aluminum did.
I'm a little worried about galvanic corrosion, seeing as a fair bit of current passes through steel > brass > aluminum. But this simple fix cost only $4.61 in parts. I'll consider buying a rivnut gun and going that route if this solution proves unsuccessful.
I tapped a 3/8"-16 hole in the (bronzed, I think?) piece on the chassis, and went bolt > 3 washers > wires > 3 washers > double nut > star locking washer > chassis. (I needed washers to fill some non-threaded space on the bolt). I applied dielectric grease around all layers, and I used stainless steel for everything, which should fare much better against salt than the aluminum did.
I'm a little worried about galvanic corrosion, seeing as a fair bit of current passes through steel > brass > aluminum. But this simple fix cost only $4.61 in parts. I'll consider buying a rivnut gun and going that route if this solution proves unsuccessful.
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The same here. My car was at the SC for the 4yr/50k, the steering bolt and the airbag recall. The Steering rack found faulted during replacement of steering rack housing bolts, so they replaced steering rack assembly. I'm pretty sure they also "thoroughly" inspected the status of this ground connection as well and found no corrosion
, so I should be good !!!
aerodyne
2 of 3 EV's - Defect Free!
Whiteblaze
Member
I just want to add my name to the list of people you've helped with this post. Thank you so much! I was getting some (not all) of the same errors plus frequent "Key fob not in car" errors. My ground bolt looked like it was attached, but it sheared right off when I tried to twist it.
While working on this, I noticed, as you did, sparking when reconnecting the ground wire to the frame. I measured a 6v difference with my voltmeter. I also noticed that the battery coolant pump tended to run a lot while not grounded, and shut off immediately when grounded. I wonder if any of this was causing some of the excessive vampire drain I've been noticing.
