cal1

The last couple of mornings when I start up the SL after sitting all night, I hear a fairly loud Rat-Tat-Tat sound coming from the engine for about a second. the sound goes completly away and I don't hear it on restart all day after the cold start in the morning. Any ideas?

alx

valve clatter. your engine is loosing up. this is actually quite normal especially for higher-mileage blown 55 cars

sticky lifters usually stick for about 15-30 seconds after a cold start and it gets worse with time. that is also a known problem and does not seem to be mileage related. some low-mileage 55 cars have gone in for service with sticky lifters...

alex
few cars

Sunir

at around or after how many miles (approx what mileage) does this start happening on 55k cars?

MBTech221

sometimes it the lil guys under the lifters, mb calls them the oil compensators, they go bad and make the same noise as lifters

cal1

I'm at about 63,000, and just started hearing the noise, but don't know if that is typical.

Sunir

1) does this symptom hurt the motor, or performance anyhow?

2) how can it be remedied/fixed? and what's the est. cost?

MBTech221

it wont hurt the engine. no performance issues from what ive ever seen. its not too hard to do. a shop would typicly charge about 5-6 hours of labor. plus parts wich im not sure. the fix is just new oil compensators.

cal1

My SL still pulls like it always has so I would say no impact as far as performance.

Quadcammer

most likely this is the result of the lifters bleeding down slightly as the oil drains or chain tensioners that have bled down a bit. As soon as the oil pressure hits them, they quiet down.

Its no big deal.