Seized Bolt: 0, Harbor Freight Drill With a Rainbow Spongebob Sticker: 1

"Mercedes Streeter" (smart)
05/22/2019 at 19:15 • Filed to: wrenching, Smart

I’ve been putting off doing the smart’s brakes since I got that Yamaha U7E. The reason for it is because I remembered that my right wheel’s rotor still had its locating/locking bolt. With me needing to drive 5 hours down to get to the start of the Gambler 500, I can’t wait any longer.

When I did my brakes in 2017, the left rotor’s bolt was seized despite use of anti-seize back when I did my brakes in 2015. Not even my mechanic friend’s impact could break it loose. He ended up having to drill through the bolt. We were able to get the right side off in 2017 and for whatever insane reason, I decided to reinstall it.

Well guess what was seized last night? Despite sitting in PB B laster for over a day, the bolt wouldn’t budge and the impact I had on loan nearly instantly rounded out the head, much like the impact from 2017 did to the left side. I take it these bolts don’t age well. At any rate, my Harbor Fright tools made short work of the bolt and reduced it to metal dust in just a few minutes.

It took me four hours to do my front brakes, two of those hours were spent fumbling around with the darn bolt trying to get it off without doing the nuclear option. Add another hour for me doing it wrong at the start.

How bad were the right pads? The inner had maybe a thousand miles left in it. The outer was close to practically disintegrating. Outer right pad wear is a common problem in smarts from brand new, so it’s just the nature of the beast.

The rotor was badly scored from the outer pad, but it actually performed better than the rotors I replaced in 2017 did, where they were just big chunks of rust.

The left pads had maybe 3-5k left in them.

DISCUSSION (9)

Future Heap Owner > Mercedes Streeter
05/22/2019 at 19:22

Nice work! Last time I had to drill out a bolt (which was also the first time) it took me uh like a week (because I’m dumb and didn’t use left-hand bits).

VincentMalamute-Kim > Mercedes Streeter
05/22/2019 at 19:30

ya, send in your photos for the obligatory JRITS brake post.

If I have to buy a HF electric tool, I find that using quality bits/blades/whatever makes a big difference.

We were able to get the right side off in 2017 and for whatever insane reason, I decided to reinstall it.

I’m assuming you did not reinstall that keeper screw this time? Right? Say yes.

Mainly I had to comment because I had no idea there was a car that used 3 studs/lug bolts.

When you say you used a friends impact, I’m assuming it was air or electric impact. As long I’m commenting, I’ve found a hand impact driver can help in these situations where a power impact won’t. The hammer pounding prevents the bit from stripping out. Don’t know if you tried a hand impact driver.

https://www.amazon.com/TEKTON-2905-8-Inch-Manual-7-Piece/dp/B000NPPATS

Manwich - now Keto-Friendly > Mercedes Streeter
05/22/2019 at 19:58

Nice work!

jimz > Mercedes Streeter
05/22/2019 at 20:40

3 lugs?

now I have seen everything!

Mercedes Streeter > VincentMalamute-Kim
05/22/2019 at 21:13

The bolt is destroyed so I can’t make that mistake again. xD

The three lugs always get a giggle out of tyre shops. I guess it’s the only car in America with such a bizarre configuration.

The friend's impact was air, the one I used last night was electric. I'll keep the hand one in mind for future rusty endeavors!

Urambo Tauro > Mercedes Streeter
05/22/2019 at 21:15

So did you end up extracting the rest of the bolt after the rotor came off, so that you could ge t a new one in there? Or just leaving it out altogether, letting the wheel hold the rotor in place?

Mercedes Streeter > Urambo Tauro
05/22/2019 at 23:21

Leaving it out entirely. The purpose of this bolt is to lock the rotor in place to make wheel mounting easier. Well, when you're dealing with three lugs and 15" wheels they really don't save you any mounting time for how long it takes to remove the bolts.

Urambo Tauro > Mercedes Streeter
05/23/2019 at 07:54

No thing wrong with that! There are plenty of cars out there that leave it to the wheel and lugs to retain the rotor. It works!

ateamfan42 > Mercedes Streeter
05/23/2019 at 09:31

The purpose of this bolt is to lock the rotor in place to make wheel mounting easier.

^^^ This. A lot of mechanics will use a lug nut to hold the rotor in place while they install calipers and such ( then remove the nut before installing the wheel) .

The little screws make the robotic assembly at the manufacturer easier, but they ALWAYS seize up and commonly have be drilled out. Personally, I’ve had about a 40% success rate getting them out with an impact screwdriver. Don’t bother replacing them.