Is it too much trouble to bring your car down to Mr. MB Motors in Tarzana, CA?
There are a lot of high fives about Enrique's shop and his level of expertise in the Good Shops Forum.
He is I guess in his middle 50's, and has been working on Mercedes cars at Mercedes dealers since he was 18 years old, first in Spain (where he was born and raised), then Argentina, then South Africa, and finally at two Mercedes dealers in California - the one in the San Fernando Valley, and the dealer in Beverly Hills. He has operated his own shop for about the past years.
I was just there again last Thursday, and the local Mercedes dealer brought in an R129 SL500 that they couldn't diagnose and asked Enrique to take a stab at it.
I couldn't believe it! Enrique says they bring in cars from time to time that even their best techs can't handle.
Here's the deal on that car - the car was pinging real bad, and the dealer assumed it was a burned valve, but after taking the head off, found that the valves were fine.
While I was waiting in the shop, Enrique checked the timing of the valves and found that it was not right. Apparently, a previous mechanic had done a timing chain on this engine, and left off the woodruff key! The key goes in the crankshaft. The timing chain connects to the crankshaft via a sproket that slides over the crankshaft. This sproket is held in alignment by a woodruff key. They make more keys that slightly offset this gear a few degrees which you could effectively advance and retard camshaft timing, or if it makes it more clear, retard or advance crankshaft timing.
Anyway, Enrique was laughing to himself at the end of the day when he discovered this. He was originally the Shop Foreman at the dealer, and he told me that out of the 38 technicians they have there, maybe 2 are really good. That's right, just 2.
And the good thing about Enrique, is that he has all the parts and all the diagnostic equipment, and he never replaces parts willy-nilly when troubleshooting a problem. Diagnosing problems requires testing, and that above mentioned SL 500, I popped my head in while he was troubleshooting it, and he was explaining to me all the things he had tested before finding the problem was the woodruff key.
2001 E430, Bourdeaux Red, Oyster interior.
1973 280SE 4.5, 170,000 miles. 568 Signal Red, Black MB Tex. "The Red Baron".