Mercedes-Benz Forum banner

1 - 6 of 6 Posts

·
Registered
Joined
·
147 Posts
Discussion Starter #1
Hello all,

My 280SL has about 100k miles. The timing chain barely lifts off the timing gear teeth. Nevertheless, at what mileage should it be replaced?

Thanks,

Laverda
 

·
Premium Member
Joined
·
3,185 Posts
Congratulations. You have hit the magic "time to replace the timing chain " moment in your car's career. Conventional wisdom is 100 k.
 

·
Outstanding Contributor , Bob's Your Uncle!
Joined
·
29,067 Posts
Well, not so fast. The M110 doesn't share the same characteristics of the 3.8, 4.5 or 5.6. One of the big differences are the rails. They are rubber lined rather than plastic / teflon . They wear slower and don't break. the tensioner has quite a bit of travel and will keep the chain taut. When it is time, you will hear a rattle on start up which, in my case, meant the tensioner had come to the end of it's travel, which meant the chain had stretched. There were also
grooves worn in the rubber of the rails.
All this with 145K.
Laverda, if you have the time and money available and will sleep better by changing it then you have your answer.
 

·
Registered
Joined
·
147 Posts
Discussion Starter #4
Hi Dugald,

Thanks. The noise is caused by chain slack that cannot be tightened by the tensioners, ie slack between the links that is sufficient, say between three or four links, to cause float on sprocket teeth. Motorcyclists know about chains, eh.

I did not know the tensioners were rubber covered. This is great, as you can go incremental: you check wear - groove depth-, and if it looks ok, you replace the chain only. And then if it gets noisy at say 160k miles, you know it's time to change the tensioners, a big job. But if you're careful the tensioners will last well over 200k, the slack being taken up by the chain tensioning piston. Teflon heel surfaces on tensioners tend to go bang after a while, not rubber.

One thing is that uneven firing strokes (like on a Laverda 3 cyl or a 6 cyl from a V8, or an inline five) tend to jerk chains and cause premature wear. An inline six is near pefect in harmony, nothing better really.

So, timing chain replacement is on my winter project list.

Laverda
 

·
Premium Member
Joined
·
6,077 Posts
Today I went to see two M110 engines. A 1968 280SL and a 1969 280SE. The SE has 455,000 miles. No, that's not a typo. It's on the second engine and it still runs. The wood has been refinished once, but it's far past that now. I gave them websites and talked upholstery and carpeting. I also gave them the name of what I hope will also be my new shop. They were featured in The Star magazine, and they're about 60 miles north of here. I've asked around and they have a good reputation.

The cars have sat (garaged) for a year, but the owners want to restore them. Interior, exterior and mechanical. They'll be beautiful when they're done.
 
1 - 6 of 6 Posts
About this Discussion
5 Replies
5 Participants
Fotografa
Mercedes-Benz Forum
BenzWorld.org forum is one of the largest Mercedes-Benz owner websites offering the most comprehensive collection of Mercedes-Benz information anywhere in the world. The site includes MB Forums, News, Galleries, Publications, Classifieds, Events and much more!
Full Forum Listing
Top