TECH
Owning an R129 – Some Technical Considerations
Article & Image Bill Brandt
As the owner of a 1996 SL500 for six years this January, I enjoyed the recent Buyers Guide article on R129s (September-October 2018). I really enjoy the car. It was designed by Bruno Sacco, who was acknowledged by Automobile Magazine as one of the 25 most influential designers of all time; heady company included Sergio Pininfarina and Bill Mitchell. And Sacco considers the R129 to be his best design. I agree with him. How many people get consistent thumbs-up signals from other drivers and pedestrians with an affordable 22-year-old car, even one that cost $89,900 when it was new?
The only downside for me is that I’d hate to add up the receipts I have accrued; I am most certainly “upside down” in the car. The upside? I have a fantastic automobile that in my opinion is one of the best-looking SLs ever made – one that I could take across the country tomorrow. I think my enjoyment has been worth the cost.
But there are some downsides to be cautious about. For those who are considering buying one of these affordable (but appreciating) classics, a few facts:
1. Interior plastics: Between the quality of the interior plastic and experience from most owners, 20 summers of the sun’s rays baking a topless interior can disintegrate the plastic trim. Some of those interior pieces are unavailable now. Others, like the sun visors, list at $700. The plastic mount in my visor holding the vanity mirror broke; because the removable mount was not available as a separate part, I paid $200 for a used visor at an SL recycling yard.
2. Engines: The interesting thing is that the M119 V-8 is almost bulletproof: A new replacement long block lists at $14,000, but recycling yards have them hauled away for the metal. There’s just no demand for them. However, after 1993, the parts were scrutinized by the bean counters and they substituted plastic for wonderfully machined oiler tubes for the second cam; but I got them off a 1992 400E in a pick-n-pull yard. Aluminum ones are available from several third-party sources. That is the only weakness for post-1992 M119 engines. My 1996 with OBD II, of course, got electronic ignition and a revised fuel-injection system; mileage noticeably improved. I get 20 mpg in town and 23-24 on the road. With routine maintenance, I believe that the R129 V-8 will go on nearly forever.
3. Keys: I recently learned (at a Mercedes-Benz enthusiasts’ website) that replacement ignition keys with remote door lock/unlock functions for these cars – at least for MY 1997-1998 – are not currently available. Reportedly, the original supplier of the circuit boards is no longer in business and the company has not yet found another company that can make replacements. On the 1996 cars, the electronic key is not available, although the conventional key is. Neither is available for the 1997-1998. So if someone is interested in buying one of these cars, I would certainly make sure both sets of keys are with the car.
4. The truth about the 722.6 5-speed electronic transmission: Your chart in the Buyers Guide indicates the 722.6 5-speed (5G-Tronic) automatic transmission was introduced in 1998 when the engine was changed. In fact, the 5-speed transmission was introduced on the V-8 cars as part of a minor model change in 1996. For my 1996, it was the first year and, at 180,000 miles, I had to have it replaced. It is my understanding that it underwent three major revisions, but by mid-year 1998 it was made pretty robust. Make sure in the records you see evidence of transmission fluid/filter changes every 40,000-60,000 miles.
5. Top Mechanism: This was the first car that offered a hydraulic system for raising and lowering the top. Depending on the model year, the mechanism has 11 or 12 hydraulic cylinders with seals that now tend to leak. The most common to fail first are those above the sun visors. You will see hydraulic fluid leaking into the interior when these two go bad. I had to have this repair carried out this past summer. Several advertisers in The Star provide replacement parts, but expect to pay $2,000-$3,000 to have these replaced, unless you do it yourself.