Unsuccessful day in 190D - PeachParts Mercedes-Benz Forum

w123fanman · #1 03-31-2013, 12:18 AM

Day started out by going over to my mechanic's to have him try to remove the lug bolts on the back wheels so my friend and I could adjust the parking brake. He was able to loosen all of the bolts on the driver's side wheel but only 3 on the passenger side. One of the bolts still won't move and another snapped its head off so it will have to be drilled out next week. He said that he did not understand why they would not come out as he did not over tighten them when he re-installed the wheels after replacing the brake discs and pads and said it was probably because of how off the wheels desperately need an alignment. So we went over to one alignment shop and they said that they cannot work on Mercedes so we went to Kauffman Tire who wanted an extra $40 because it is a Mercedes, therefore it has "premium suspension" (total cost $120). They told us it would be 2 and 1/2 hours to get it done (usually takes an hour but there was a car ahead of us) so we get back there 2 1/4 hours later, wait 15 minutes and then the guy we spoke to earlier said that they could not do the alignment because the tires in the front were smaller than the ones in the back and we would have to replace those tires if we wanted them to do the alignment so we said no and took the car and left. I refuse to ever go back there because I do not want to buy tires just for the heck of it because I am 100% sure alignments on a Corvette are possible to do even though the tires on its back wheels are bigger than the ones on the front, as on many other cars. During those 2 &1/4 hours we were waiting, we went back to my friend's house and bled the brakes on another of my friend's 88 Ford Ranger. After that we did a 0-60 test and the 190D did it in 18 seconds which I assume is slower than it is supposed to be seeing as the 240D is supposed to do it in 18 seconds. Next we went back to my house and figured out that our auxiliary fan was not working because the incorrect relay was installed (we were having issues with the temperature in the car going way up) but the fan still doesn't come on when the engine gets hot which might be the coolant temp sensor or the AC switch on the center console (doesn't seem to work, probably needs to be cleaned like all of the other switches in the car) or something else that could be corroded.

Stretch · #2 03-31-2013, 02:10 AM

Well I agree with you on your reaction to the alignment place - what a load of crap - don't go there again.

As for broken wheel bolts - if they were removed recently then it would seem most likely to me that who ever put them back on over tightened them. If we were talking about a car that had been sitting in a field for 15 years then I'd blame corrosion...

...please do us all a favour in the future and put in some white space line breaks in your long posts it makes them so much easier to read!

t walgamuth · #3 03-31-2013, 05:46 AM

I agree. Your mechanic probably overtightened. they have a specific torque value. On a 123 I believe it is 75 to 80 foot pounds. I have had tech's guess that it is 120#. The powerful air guns can easily wreak havoc by over tightening.

The broken off ones may actually come out quite easily now that the torque is gone from them.

JB3 · #4 03-31-2013, 07:36 AM

Guy does the brakes for you, then later cannot remove the wheel lugs and blames the alignment??

That's the most preposterous thing I've ever heard. As already said, two things prevent
Wheel lugs/bolts from coming off, corrosion/rust combined with time, and overtightening.

If the brakes were just done, then he overtightened the lugs, and it sounds like he dangerously overtightened them. Id make sure the front ones aren't overtightened too, this is how tires fall off due to overstressed wheel lugs/nuts.

Id find a non rip off alignment place, and id also find a mechanic who won't lie to you like that when things are clearly his fault, or at least won't lie as stupidly as that. Next he'll be telling you your brakes are squeaking because you've been listening to too much talk radio.

mespe · #5 03-31-2013, 08:21 PM

I would have to agree with the tire store about the alignment.
Smaller tires change the angle of the adjustment, how much I don't know, guess it depends on the difference between the tires.

AFA the vette example, the vette was designed for smaller tires on the front, and thus the alignment in the book can be followed.

Now it was possible to align your car, but as soon as you bought a set of new tires of the correct size, the alignment would be off, and the tires would wear prematurely.

t walgamuth · #6 03-31-2013, 09:49 PM

If your tires were same diameter the alignment specs should not change.

Volker · #7 03-31-2013, 10:11 PM

I don't see how mech couldn't get them off, maybe he put it too tight with his impact wrench (idiots) but just take a breaker bar and a pipe and it comes off.

I don't think he tightened to 120 ft-lbf which is still not a lot. If he can't get it off it is in the 300's or more. With pipe you can easily develop 1000 ft-lb but you will break sockets and such

I should take a picture of the mangled MB lug wrench I have from my CLK because of such idiots with their impact guns...

satyr · #8 04-01-2013, 01:28 AM

I had a nice C4 corvette once upon a time, and while the alignment specs were debated ad nauseum on the corvetteforum, and there were a few schools of thought about what was "best", it was possible even though the front and rears were different- and nobody charged nobody an extra $120 to dial them in. And- I'd find another shop to work on the 190 for you- he likely used a torque wrench to re-install your wheels/tires after the brake job- and is now whining that they are on too tight, which is why he can't get them off now.