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  #1  
Old 11-04-2002, 05:34 PM
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timing chain degree allowance- 1985 380 sl

My friend and I drove his 1985 380 SL with 77,000 miles ran PERFECTLY all day then, when it was time to go home---- no start. Had (BAD MISTAKE) a mobile mechanic tow it to his place... Was told that the timing chain need replacement. QUOTE:" the chain is a few degrees off -that's why it doesn't want to start". I think he's full of it. HAd it towed to my place and will do the investigating of my own. WHERE SHOULD I START??? Is this true that timing chain slacking will prevent a totally perfect running car to not even start????? It doesn't even have any timing chain slp on initial start that morning.And it's double chained already!I was thinking fuel pump relay or fuel accumulator -- talk to me mercedes experts!!!

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1978 280 CE silver
1986 560 SL black
1987 300 SDL cream
1994 SL 500 brilliant green
1997 E 300d dessert silver
2005 FORD F250 Superduty Crew cab 4x4

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  #2  
Old 11-04-2002, 05:38 PM
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4 degrees of stretch is considered the limit.
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2001 E430, Bourdeaux Red, Oyster interior.
79,200 miles.

1973 280SE 4.5, 170,000 miles. 568 Signal Red, Black MB Tex. "The Red Baron".
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  #3  
Old 11-04-2002, 05:43 PM
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4 degree stretch

well, considering the stretch, would this make the car not start at all? Isn't this issue a progressive problem ie: will start hearing slap in cold starts, idle and perform rough, poor gas mileage?

There were none of these signs to begin with...


Thanks so much for the reply- this is very important information!
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a2


1978 280 CE silver
1986 560 SL black
1987 300 SDL cream
1994 SL 500 brilliant green
1997 E 300d dessert silver
2005 FORD F250 Superduty Crew cab 4x4

____ADMU____
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  #4  
Old 11-04-2002, 05:58 PM
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I don't think the timing chain stretch will prevent your car from starting. It might put your timing a little off, though.

You probably have other problems.

How long has it been since the timing chain and upper rails were replaced anyway?
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Paul S.

2001 E430, Bourdeaux Red, Oyster interior.
79,200 miles.

1973 280SE 4.5, 170,000 miles. 568 Signal Red, Black MB Tex. "The Red Baron".
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  #5  
Old 11-04-2002, 06:02 PM
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rail replacement

@ 77,000 miles....I doubt it if he had this done ; but who knows?
I need to get busy and start investigating -- just want to get the darn thing started again just to rule out that timing chain would not cause a car not to start esp. if the chain didn't fail in the first place. Thanks
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1978 280 CE silver
1986 560 SL black
1987 300 SDL cream
1994 SL 500 brilliant green
1997 E 300d dessert silver
2005 FORD F250 Superduty Crew cab 4x4

____ADMU____
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  #6  
Old 11-04-2002, 06:16 PM
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Regardless of your starting problem, don't ignore your timing chain. Timing chain stretch is very bad on these engines.

The chains do stretch on these M116 and M117 engines over time, because the chains are long and change direction many times as they travel from the crank at the bottom up to each cam on each side of the "V".

Most members and techs on this site recommend replacing the chains approximately every 100,000 - 120,000 miles. 4 degrees of stretch is considered the time to change the chain.

Further, it's not just the chain that's the problem. The chain guide rails are made of plastic, and become hard and brittle over time, as well. As the chain stretches it becomes loose, and starts to rattle and bang and slap against the guides. It usually happens at start-up, but when the chain gets loose enough and the guide rails are old and brittle enough, the chain will slap against the plastic and it'll break apart. Plastic pieces will get stuck in the chain and the sprocket, and bam!, you've bent a camshaft, pistons will hit valves, etc.

I've found from reading posts on this site, that's it's more often a loose chain breaking old guide rails, than a loose chain jumping a sprocket that causes an engine failure.

Either way, your car is probably due at minimum for the replacement of the upper guide rails. I'm sure the plastic has turned a dark brown color and the plastic is surely brittle.
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2001 E430, Bourdeaux Red, Oyster interior.
79,200 miles.

1973 280SE 4.5, 170,000 miles. 568 Signal Red, Black MB Tex. "The Red Baron".
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  #7  
Old 11-04-2002, 07:00 PM
Bud
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I may be confused but I seem to recall that these engines have a simplex timing chain and that it should be upgraded to a duplex chain. It's been a while but I think the cost to do it was sround $2,200.
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  #8  
Old 11-04-2002, 07:10 PM
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dual timing chain post 1983 1/2

I believe that the post 1983 1/2 was coverted to dual chain. The faulty chains were in the 1980-early83 cars.

Suginami,

I got your point. Makes all the sense in the world. Thanks for your input. We'll probably go ahead and change the rails and the chain as well.

regards
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a2


1978 280 CE silver
1986 560 SL black
1987 300 SDL cream
1994 SL 500 brilliant green
1997 E 300d dessert silver
2005 FORD F250 Superduty Crew cab 4x4

____ADMU____
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  #9  
Old 11-04-2002, 07:11 PM
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I think you're right.

The '81-'83 had the single row chain and it should be converted to the double row chain if it hasn't already. If not, it needs to be replaced every 30,000 miles.

The '84-'85 380 SL's came from the factory with the double row timing chain.

FWIW, in Europe they always used the double row timing chain starting in '81. Why the brilliant engineers at MB went with a single row in the U.S. is a mystery...
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Paul S.

2001 E430, Bourdeaux Red, Oyster interior.
79,200 miles.

1973 280SE 4.5, 170,000 miles. 568 Signal Red, Black MB Tex. "The Red Baron".
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  #10  
Old 11-04-2002, 07:12 PM
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Re: dual timing chain post 1983 1/2

Quote:
Originally posted by a2aa
I believe that the post 1983 1/2 was coverted to dual chain. The faulty chains were in the 1980-early83 cars.

Suginami,

I got your point. Makes all the sense in the world. Thanks for your input. We'll probably go ahead and change the rails and the chain as well.

regards
and tensioner.
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Paul S.

2001 E430, Bourdeaux Red, Oyster interior.
79,200 miles.

1973 280SE 4.5, 170,000 miles. 568 Signal Red, Black MB Tex. "The Red Baron".
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  #11  
Old 11-04-2002, 07:17 PM
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tensioner

GOT IT!!

thankyou
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a2


1978 280 CE silver
1986 560 SL black
1987 300 SDL cream
1994 SL 500 brilliant green
1997 E 300d dessert silver
2005 FORD F250 Superduty Crew cab 4x4

____ADMU____
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  #12  
Old 11-12-2002, 01:21 PM
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AN UPDATE:

opened the valve covers: broken chain guides .. and all 4 of them too!! The chain was intact. The only thing I don't get is this thing got new guides and chain back in 1997- 15-20 k miles ago. Why the failure?

Regards
__________________
a2


1978 280 CE silver
1986 560 SL black
1987 300 SDL cream
1994 SL 500 brilliant green
1997 E 300d dessert silver
2005 FORD F250 Superduty Crew cab 4x4

____ADMU____
Reply With Quote
  #13  
Old 11-12-2002, 03:35 PM
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Join Date: Oct 2002
Location: Texas
Posts: 303
AN UPDATE:

opened the valve covers: broken chain guides .. and all 4 of them too!! The chain was intact. The only thing I don't get is this thing got new guides and chain back in 1997- 15-20 k miles ago. Why the failure?

Regards
__________________
a2


1978 280 CE silver
1986 560 SL black
1987 300 SDL cream
1994 SL 500 brilliant green
1997 E 300d dessert silver
2005 FORD F250 Superduty Crew cab 4x4

____ADMU____
Reply With Quote
  #14  
Old 11-12-2002, 06:04 PM
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Maybe the tensioner wasn't keeping the chain properly tight?
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Paul S.

2001 E430, Bourdeaux Red, Oyster interior.
79,200 miles.

1973 280SE 4.5, 170,000 miles. 568 Signal Red, Black MB Tex. "The Red Baron".
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  #15  
Old 11-12-2002, 06:12 PM
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Quote:
Why the brilliant engineers at MB went with a single row in the U.S. is a mystery...
Maybe the brilliant engineers figured they did not need the double row chain in the land of 55 mph speed limits .

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