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Discussion Starter · #1 ·
My 380 drives beautifully, but has one problem I just can't figure out.

Just about every time I put my foot down on the accelerator, there is a one or two second hesitation before it kicks in.

I have changed the air filter, filled up with premium gas and put an oil treatment in for good measure, but still the same problem.

I also BTW have a 560 timing chain.

So can anyone recommend a course of action I should try next?

many thanks,
 

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2024 SL770
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My 380 drives beautifully, but has one problem I just can't figure out.

Just about every time I put my foot down on the accelerator, there is a one or two second hesitation before it kicks in.

I have changed the air filter, filled up with premium gas and put an oil treatment in for good measure, but still the same problem.

I also BTW have a 560 timing chain.


So can anyone recommend a course of action I should try next?

many thanks,
Try using the proper timing chain, the 560 chain is 12 links too long...
 

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^ Yup, there's your hesitation right there.
 

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Forum Administrator , RC Colas® & Moon Pies®
1981 380SL 151K: 2005 S500 116K
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^^^
Now hold on just a gosh darned minute there. It's a self correcting problem. That 12 Link Lag (LL) becomes a 24LL on its second circuit, followed by a 36LL and so on until about the 8th or so time during which it should run like a raped ape.

Then there's a 12 LL followed by...
 

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^^^
Now hold on just a gosh darned minute there. It's a self correcting problem. That 12 Link Lag (LL) becomes a 24LL on its second circuit, followed by a 36LL and so on until about the 8th or so time during which it should run like a raped ape.

Then there's a 12 LL followed by...


And what, pray tell, tragic, traumatizing incident must have occurred in your life, to foster your expertise on how an ape, once raped, should run, link lag notwithstanding.


 

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Forum Administrator , RC Colas® & Moon Pies®
1981 380SL 151K: 2005 S500 116K
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It's called the interwebs. I never knew what a "cuban cigar" was until someone on an different forum posted a link which I would have been much happier had I never clicked on it.

Urban Dictionary: cuban cigar
 

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Always Remembered RIP
1973 450 SLC AMG, 1995 Chevy Tahoe
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Discussion Starter · #12 ·
OK how about a serious response folks!!
 

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It was. IF you have a 560 chain on a 380 gear set, the longer chain results in retarded cam timing in relation to the crankshaft. That would cause a serious low power issue at low rpm's, and reduced power overall.

Click on GermanStar's sig, you'll see he has a certain flair for MB parts.
 

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Discussion Starter · #14 ·
OK sorry. So is this remediable at a reasonable risk/reward ratio?

Or should I just put up with what is in fact just a minor irritation.

Many thanks
 

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Forum Administrator , RC Colas® & Moon Pies®
1981 380SL 151K: 2005 S500 116K
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Dave, how is that even possible? Twelve links? What akes up THAT much slack? And to the point of my first post, if the timing is retarded the first time around, isn't it doubly so the second and so on?
 

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Dave, how is that even possible? Twelve links? What akes up THAT much slack?
I'm not sure it is possible. I'd like to know how learnix determined the chain is in fact a 198 link, rather than the correct 186 count. And if he didn't install it himself, what technician should be put on the avoid list

And to the point of my first post, if the timing is retarded the first time around, isn't it doubly so the second and so on?
It's not progressive. Picture four clocks, one at each point of the compass, all at 12 o'clock. N and E are your cam gears, S is the crank and W is the tensioner which is not a gear, just a slider. The chain wraps around the outside of N, E and S. It winds inside of W, which pushes inward to tension the chain. When the chain lengthens beyond the travel of the tensioner, it gains slack around the compass, but the number of links between the teeth remains constant. S, the crank, pulls the chain. Slack between S and E retards that E cam, to say 11:55. Further slack between E and N retards the N cam five more minutes, which puts it at 11:50 in relation to S, the crank. Unless the chain jumps, the number of links does not change hence the timing is retarded, yet constant.

But with that said, I think twelve links is far too much for the tensioner to make up for. Again, I hope learnix responds for our edification.
 

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Discussion Starter · #17 ·
Sorry I may have given the wrong impression.

I have had the car since new in 83 and a few years later the engine seized in Torontop and MB said the timing chain had gone. The service advisor recommended that I replace it with a 500/560 timing chain rather than a 380 and $5,000 later I saw the improvement in performance.

In my original post I wanted to provide as much information as possible, not thinking for one second that the timing chain could be important and relevant to my problem.

The hesitancy is not a show stopper, just an annoyance that would be nice to fix if the cost is not too great.

Thanks again
 

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I have had the car since new in 83 and a few years later the engine seized in Torontop and MB said the timing chain had gone. The service advisor recommended that I replace it with a 500/560 timing chain rather than a 380
I'm going to guess - and I know that's dangerous, but I'll do it anyway - that what actually happened was the chain got converted to a "560 style" double-row chain. Not that an actual 560SL timing chain got installed.
 

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Sorry I may have given the wrong impression.

I have had the car since new in 83 and a few years later the engine seized in Torontop and MB said the timing chain had gone. The service advisor recommended that I replace it with a 500/560 timing chain rather than a 380 and $5,000 later I saw the improvement in performance.
Yeah, that's how I read it....

For future reference, you do not have a 500/560 chain. Your M116 3.8L (380) engine was originally equipped with a single row timing chain and gear set. After the initial chain failure, your $5,000 bought an upgraded, double row chain and gear set of the same style as the M117 (450/500/560), in the correct configuration for your M116.

As to the problem at hand, it sounds like either an ignition, distributor timing, or or fuel delivery issue. How long since your last maintenance cycle? Has your fuel mileage worsened noticeably? It may be time for a full on tune up.
 

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Forum Administrator , RC Colas® & Moon Pies®
1981 380SL 151K: 2005 S500 116K
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I'm not sure it is possible. I'd like to know how learnix determined the chain is in fact a 198 link, rather than the correct 186 count. And if he didn't install it himself, what technician should be put on the avoid list



It's not progressive. Picture four clocks, one at each point of the compass, all at 12 o'clock. N and E are your cam gears, S is the crank and W is the tensioner which is not a gear, just a slider. The chain wraps around the outside of N, E and S. It winds inside of W, which pushes inward to tension the chain. When the chain lengthens beyond the travel of the tensioner, it gains slack around the compass, but the number of links between the teeth remains constant. S, the crank, pulls the chain. Slack between S and E retards that E cam, to say 11:55. Further slack between E and N retards the N cam five more minutes, which puts it at 11:50 in relation to S, the crank. Unless the chain jumps, the number of links does not change hence the timing is retarded, yet constant.

But with that said, I think twelve links is far too much for the tensioner to make up for. Again, I hope learnix responds for our edification.
With that explanation, you might have just become my Luke.

http://www.benzworld.org/forums/off-topic/1376204-whos-your-luke.html

Well. You're at least in my top 10.
 
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