C230 Sport Coup

Anybody here ever inflate their space saver spare? I've never used mine. But I got a flat on the rear tire and I got tired of it sitting up on a Jack in the garage since the slime Tire plug kit did not work correctly. I've done it twice now and at least worse than the screw that was in there. I would have been better off leaving the screw in.
​​​​​So for the time being I inflated the space saver spare and it blew way out on the one side facing the outside of the car. Is this normal? See my photos please. I just wanted to be able to move it over in the garage because I had it way off to one side. I don't plan on driving it. But what if I ever needed to? It wouldn't fit on the front anyway because I have the AMG brakes. Let me know your thoughts on my photos is this normal?

slammer111

If the bulge is symmetrical between outside and inside then it's probably correct. Guessing it has something to do with the space saver design.

C230 Sport Coup

Do you still have yours?
Ha, just for fun pull it out and see what happens.
At least you'll know if it holds air.
Perhaps stand back somewhere in case it explodes.
I mean, what it's a 22+ year old tire!!
So, I ordered these tire screws that are rubber with sealant on them, and screw in the hole.
I'll try that, (50 of them for $7 on Amazon!) and also apparently the best tire plugs are made
by a company "Safety Seal" made in USA. A little expensive though.
The slime plug is leaking THROUGH the rope, not around it.
Chinese crap.
Local shop refuses to patch it, as it's about 1" away from the sidewall.
From what Ive read up to a 1/2" is OK. Tire is basically new!! ~3K miles on it.
I had to toss my nearly new Sumitomo's that had been on the car
for ~3-5 years, but not driven much in that time.
Sat for 2 years needing repairs. And the tread seperated on all of them with ~5k miles on them!!!
No sumi dealers around here, so I had to eat it, and buy another set, this time Khumo.
So shop want to sell me a tire for $150 OR $50 to mount and balance a tire I provide,
up from $25 not a year or so ago when I bought the Khomos. To hell with that!!
Maybe I'll made a youtube video about the various methods and which ones work
and still hold after 6 months or something.

slammer111

Yeah I have mine still, as well as everything else in the compartment. Always wondered how people lose parts that come with their car.

Looks like the bulge is supposed to be there, on both sides.


Looks like these things are designed to be collapsible. In other words, they can be reused.

Also learned that the pointy cap doubles as a schrader valve tool.

C230 Sport Coup

Hmmmm....
Well I only went to 30psi.
Max is 40 psi. It looks so goofy I was afraid it would explode.
I guess I'll try going to 40psi.
From a distance. LOL

slammer111

Here's a video of a MB donut.


Looks like it's supposed to be inflated to 40psi, at which point it actually looks surprisingly like a regular tire. If this is the case, then the tire in your photos is underinflated.

C230 Sport Coup

Thanks Slammer, I set the pump to 40 psi an stood a good distance
away until it was done. I didn't take it off the car so I can't see the back very well.
I did jack up it up so there's be no weight on it, it does now appear to be more symetrical.
That guy's tire was sticking out in the back, mine was in the front. It was riding on the sidewall a bit.
Seems better now.
Once I'm finally get the problem with the real tire resolved, I'll pull it off and get a good look.
I'm receiving these 'tire screws' from Amazon tomorrow, going to give that a try,
and if that doesn't work I ordered some "Safety Seal" tire plugs off ebay.
https://bobistheoilguy.com/forums/th...estion.226973/
Supposedly the best tire plugs, made in USA.
BTW- Just checked the owners manual, it specifies 36 psi.
40 is the max as shown on the tire. But not driving it anyway, just need to move it in and out of the garage.

C230 Sport Coup

So the tire screws are a success, and yes, with the spare at 40 psi it becomes more symetrical though the manual calls for
36psi. I would not want to actually have to drive on that thing!

Petethepug

Narrow rim, full size tire. Win, win. That’s cool engineering that the outside of the tire is wider to get you more contact patch on the pizza cutter rim.

What brand is it? Vredestein?

C230 Sport Coup

Narrow rim, narrow tire.
Yes I do believe it is Vredestein.
Made of unobtanium so I've read.
I fixed the flat and all is good.