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1997 S420
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16 Posts
Discussion Starter #1
Hello,

Engine started making some noises the other day.

Here is a video, hope the sound is clear enough.

YouTube - 1997 S420

The faster i drive the more often the knocks

its a 97 S420

Anyone have any ideas what can be the problem??
 

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SL55, 300SE, GL450, Daytona 955i
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10,293 Posts
one of the oil lines is broken and needs replaced. search the board and you'll find the "how to".
 

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1997 S420
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16 Posts
Discussion Starter #5
I have read that guide, its very good, just wanted to hear more opinions.

Also guys, how hard do you think the job is?

For a person who is not too familiar with cars.

Is there any special tools needed? and how much would this be at the mechanics?

Thanks for all the help
 

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Premium Member
1997 S600 (sold)
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4,660 Posts
It may be a ticking lifter, but before you go dismantling the engine, you'll want to rule out the other obvious things first, such as anything having to do with the belt, fan, and accessory pulleys on the front of the engine. A mechanic's stethoscope on the valve cover would be a great way to tell if the noise is from a lifter under the valve cover.

Brett
 

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1997 S420
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16 Posts
Discussion Starter #7
I dont think its the belt or the pulleys, going to the mechanic tomorrow.

If its the oil lines, whats actually making the noise?
 

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oil tubes/lines

oleg45 said:
I dont think its the belt or the pulleys, going to the mechanic tomorrow.

If its the oil lines, whats actually making the noise?
What makes the noise is the design of the engine uses little (unfortunately) plastic tubes to move oil from the bottom of the engine to the top. They are designed to pop off should an overpressure occur. When this happens there is no oil getting to the cam/lifter and it becomes metal to metal. The good news is that these engines are very tough and you have to run it for a very long time to do any damage. I know. I've replaced mine five times. It costs anywhere from about $400 to $1000, depending on who you have do it.........or you can search the forum and find several very good descriptions, including pix, on how to do it yourself....cost: about $200-$250. I now run lower viscosity oil and haven't had it happen in nearly a year.

Having said all that, your noise seems a lot louder than mine ever did. It may be something quite different. In fact, I'd bet on it.

Best of luck,

M.D. Moore
 

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1997 S420
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16 Posts
Discussion Starter #9
Well, had the mechanic change the oil guides plus the gaskets. The noise is gone, but engine running i think sounds a little louder than before. Maybe just need some time?
 

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94 s420 98 s420
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539 Posts
Thanks updating the thread, atleat we now know that broken oil tubes can make pretty severe knocking, you think its possible you can shoot another video so we can compare noise. How much did they charge for this job? thanks.
 

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1997 S420
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16 Posts
Discussion Starter #11
I'll try to make another video tomorrow.

The dealer wanted $2200 CAD (with parts)
At different other places got quoted around $650 CAD got it done for that much including parts (16 oil tubes, 2 gaskets - $400CAD)
 
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