27th Feb 2002, 16:43

I echo that: I owned a 1990 420 SEL for 5 years (just sold it) and it too threw the timing chain at around 100K. However, the true culprit may be the chain tensioner. The tensioner is on the right side of the engine just above the oil filter. This part relys on maintaining oil pressure between starts to keep the timing chain tight. When it fails it allows the chain to "slap around" on start up, possibly jumping a timing gear. But the car was still beautiful and a joy to drive.

23rd May 2002, 00:00

I am driving an 87 420 SEL everyday that has 340,000 miles...

M.Martin, Gatlinburg, Tenn.


23rd Jul 2002, 08:32

Bought our '89 420SEL 3 years ago with 98K miles. Paid too much, but it looked like new. Has 130K miles now. Needs timing chain, etc., etc. Thought about trading, but can't think of another car we'd rather drive that would cost less than $30K. So we're going to give this baby whatever it needs (including new paint), and drive it another 100K. Love this car!

30th Aug 2002, 13:07

I purchased a 1987 420SEL Mercedes about five years ago, with 130,000 miles on it and it now has a little over 200,000 miles. It has been one of the most reliable vehicles that I've ever owned and I plan on keeping it. My wife and I are in the market to buy another car soon and without a doubt it will be another Mercedes, I won't ever by anything else.

11th Feb 2003, 21:10

What a car! I was going to purchase a 1986 300 SDL, but the 420 fell into my lap for a price less than a 1980 Toyota! Power, elegance, room, ride. A true breathtaking gem. I wish I could find the original selling price in 1987.

25th May 2003, 16:34

I have the 1987 Mercedes 420 It has a great ride, but lately I have been having lots of trouble starting it. I changed my starter, battery, spark plugs and the very expensive cap and rotor. For some reason the car will only start in neutral. Is this a sign that the timing chain is going or should I leave well enough alone? Car is The 1987 Mercedes 420 at 225,000.

26th May 2003, 19:26

"...For some reason the car will only start in neutral. Is this a sign that the timing chain is going..."

Transmission position is unrelated to engine starting/running problems caused by the timing chain. If you are unsure about the timing chain though, replace it.

The symptoms you describe are much more likely to be caused by:

1. transmission not completely engaging in park

2. faulty park/neutral safety switch.

I don't know of a specific way to distinguish between these two... I would take it to your mechanic, describe the symptoms and see what the mechanic says. And, in any case, ask the mechanic to replace the park/neutral safety switch. If that doesn't work, ask the mechanic to adjust the shift linkage (which should fix problem #1).

27th May 2003, 10:50

The park/neutral safety switch and the linkage is what I will zero in on. This information is much appreciated. What are the signs of the timing chain going or the tensioner needing an adjustment or replacement? The car sound fine once started.

4th Jun 2003, 02:04

With my W124 200 Merc, it was first a load tappety rattle for the first few seconds on start up. This means that the tensioner itself is not holding the tension on the chain, and needs the oil pressure to tighten it. If these noises are present, you should immediately replace the whole tensioner. The timing chain is around £30.00 for a genuine Merc one, so it won't exactly break the bank.

I know this, as my 200 a few years ago snapped its chain, and absolutely demolished my engine. I actually ended up taking it out and bringing it to the local dump!!! But I suppose good comes out of bad, as I found an identical engine that had just been re-bored etc etc. I have just fitted a genuine chain and tensioner to it, as I was unsure of the ones fitted to it.

So what I'm saying is, if there are rattles on start up, it is of extreme importance to replace the tensioner and preferably the chain as soon as possible. I would be more than happy to explain further the noises etc, and would explain how you yourself could replace the chain, as I with little mechanical experience fitted mine, and so far there are no noises whatsoever, and the chain seems as tight as a duck's ass. Be like I was, and leave it too late, and you will be in a hell of a lot of trouble if the timing chain breaks, trust me!

6th Jul 2003, 23:20

I live in Canada and need to purchase a second vehicle to travel back and forth to my new job. There is a 1987 420 SEL for sale for $4900.00 CAN with 137,000 miles. (Approximately $3500 US) Price sound right? And other than timing chain, what kind of questions should I ask the dealer that is selling it? Is it true that I will go broke paying for the maintenance on this car?

14th Oct 2003, 16:28

No, this car will not cause a person to go broke maintaining it. Had an '87 420SEL since new. The only bad experiences were with the dealer fixing things that weren't broken, breaking things that would then need to be fixed, and not fixing broken things repeatedly. Keep in mind that the car itself is very reliable and durable.

Remember, there were so many of these cars manufactured and sold throughout the world that spare and rebuilt parts are abundant and relatively inexpensive. Find a mechanic you trust and you shouldn't have any problems.

13th Nov 2003, 11:06

I am planning on purchasing a 1987 420SEL from a friend who is willing to sell it to me for $3000. It has 90,000 miles on and I was wondering, aside from the timing chain, what else should I really worry about? He had a 75,000mi maitenance check done. It seems that it is in great mechanical condition. I own a 1987 300SDL that I am trying to sell. There is $11,000 of work that was put into the car and I just don't want to do the same with the 420. I don't have a lot of money and as I keep reading, the car is very reliable. Any advice?


27th Dec 2003, 01:52

I have recently bought a 1988 420sel it cost $14700 Australian this is quite a good price here, it is a beautiful car.The price of these new was $152.200 Australian John.

29th Jan 2004, 12:57


I just purchased a lovely 1986 420SEL with 158,000 miles on the odometer. Outside of a small dent on the RF fender, and some (hopefully) minor odds and ends the car is in pretty good condition and lovingly maintained by it's former owner of 10 years.

I've always owned big Cadillacs, Lincolns, and Buicks, and this is definitely something different for me. The body/trim fit is superior, and I really like the power from it's 4.2 litre (256 c.i.) V8, and it's lack of body lean whilst negotiating a curve. Overall it's a joy to drive, and I'm looking forward too many years of motoring pleasure from it.

I've noted the timing chain problem and so far it doesn't rattle on startup.

The transmission seems a bit sluggish shifting out of first gear, but possibly it's an inherit design flaw. I'm keeping my fingers crossed!

Any comments or suggestions would be most welcome.

Best Regards.