Under the valve covers, 2005 Mercedes SL600

[Astro14]

While changing the sparkplugs on my wife’s roadster, I discovered a minor valve cover leak.

Mercedes books about 8 hours* for a sparkplug change on the car, which has the M275 V-12 engine with 2 plugs per cylinder. Yes, that’s a total of 24 iridium plugs. since the coils have to come out to get the valve covers off, better to clean up the leak while doing the plugs.

The car was dealer serviced. 10,000 mile intervals. Mobil 1 0W40 as far as I can tell. But it was many years between each change. 52,000 total miles. Here’s how it looked.

Passenger side:

Driver side:

I used new insulator boots for each plug, and reused the coils, which are notorious for short lives. I’m hoping that the new plugs keep those coils happy.

I‘m pleased with how the engine looks. I took a look down each cylinder with my scope. Cylinder walls look perfect. Tiny bit of carbon above the ring travel. Tried to take pictures of them as well, but I clearly didn’t remember the scope directions.

The engine as it sits with the beauty covers off and all the parts in place.

*A lot of intake and other parts have to come off to get the coils out. Each coil is about two feet long, and fires 12 plugs.

 

[FowVay]

That thing isn't getting driven enough. The guy should take it out on the Virginia Beach Expressway and do a few high speed runs over to the beach

 

[Trav]

That looks perfect!

 

[jeepman3071]

That looks perfect!

+1

 

[wings&wheels]

Very nice.

Those cylinder banks are probably too pretty to hide under plastic!

 

[Tdog02]

Looks really good. Needs a full Italian tune up to make sure its good to go. A redline a day keeps the carbon away.

 

[slacktide_bitog]

Looks good

 

[JHZR2]

Looks brand new. But is there a lot of scoring on the cam lobes?

 

[JavierH19]

Looks brand new. But is there a lot of scoring on the cam lobes?

Might be the light making it look worse but they do look a bit worn. I wonder if op went over them with his nail before putting it back together.

 

[SubieRubyRoo]

While changing the sparkplugs on my wife’s roadster, I discovered a minor valve cover leak.

Mercedes books about 8 hours* for a sparkplug change on the car, which has the M275 V-12 engine with 2 plugs per cylinder. Yes, that’s a total of 24 iridium plugs. since the coils have to come out to get the valve covers off, better to clean up the leak while doing the plugs.

The car was dealer serviced. 10,000 mile intervals. Mobil 1 0W40 as far as I can tell. But it was many years between each change. 52,000 total miles. Here’s how it looked.

Passenger side:

View attachment 128297

Driver side:

View attachment 128298

I used new insulator boots for each plug, and reused the coils, which are notorious for short lives. I’m hoping that the new plugs keep those coils happy.

I‘m pleased with how the engine looks. I took a look down each cylinder with my scope. Cylinder walls look perfect. Tiny bit of carbon above the ring travel. Tried to take pictures of them as well, but I clearly didn’t remember the scope directions.

The engine as it sits with the beauty covers off and all the parts in place.

View attachment 128299
*A lot of intake and other parts have to come off to get the coils out. Each coil is about two feet long, and fires 12 plugs.

So you're *saying* that MB charges roughly $1500 to change sparkplugs??

 

[Astro14]

So you're *saying* that MB charges roughly $1500 to change sparkplugs??

$1,800 was the quote 12 years ago.

That’s part of how I ended up with the S600. It belonged to a buddy, who about choked when he was quoted that for service. He realized that he couldn’t keep paying the dealer for service.

 

[Astro14]

Looks brand new. But is there a lot of scoring on the cam lobes?

Zero scoring. Must be the light. Nothing catches. Smooth as glass.

 

[Slow Car Sport Mode]

$1,800 was the quote 12 years ago.

That’s part of how I ended up with the S600. It belonged to a buddy, who about choked when he was quoted that for service. He realized that he couldn’t keep paying the dealer for service.

Two per cylinder so 24 plugs!

By the way. I LOVE these pictures!

We are but mere mortals, myself and those like me with 4 plugs. Pretending some don’t have 3

 

[Slow Car Sport Mode]

So you're *saying* that MB charges roughly $1500 to change sparkplugs??

I’m sure the typical Benzite carries that in their shoe…

When I lived in Morristown NJ (and I no longer do) it was always the Black SL that was outside of Morristown Mercedes-Benz. The generation before @Astro14 … I think Pepa of Salt N Pepa famously bought their 600SL from there.

 

[Astro14]

I’m sure the typical Benzite carries that in their shoe…

When I lived in Morristown NJ (and I no longer do) it was always the Black SL that was outside of Morristown Mercedes-Benz. The generation before @Astro14 … I think Pepa of Salt N Pepa famously bought their 600SL from there.

You would be surprised how many people without any money drive Mercedes.

Lease deals, and cheap used prices, coupled with a desire to look like they have money, puts a lot of people in MBs when they couldn’t really afford a Toyota.

It‘s commonplace to see young sailors driving $60K cars. On $25,000/year.

I‘m on a first name basis with the parts guys at my local MB dealer, having owned the S600 for 12 years, and buying parts for a 1975 450SL restoration, and now having the SL600.

They tell me stories about people crying over the cost of parts.

When the payment has already stretched your budget, an $800 part can break you. People don’t research what it costs to own a high performance German car before they buy it.

Kind of how an $1,800 spark plug change caught my buddy by surprise. He could manage it, but chose not to. He sold me the S600 and leased a new 5 series BMW. He already owns a 911. He has means, but that spark plug change caught him by surprise.

 

[SatinSilver]

Any pics of the SL? I didn't realize you had one in the fleet. Over the summer I noticed this in front of the Toyota dealer. It was clean but noticed the waves from body filler along both sides.

 

[Astro14]

I love the R107 body, like that red one.

The 1975 450SL belongs to a buddy. We spent a year taking it apart, working on engine, transmission, subframe mounts, front suspension, brakes, fuel system, interior and HVAC.

It was fun. He bought lunch and/or beer. I provided labor, space and tools. I reckon I saved him tens of thousands in farming the work out. He got his car back on the road.

I would not recommend a 1975-76 R107 however, as in those two years only, Mercedes integrated the cats into the exhaust manifold, causing the heat to roast the wiring, which caused issues, and the car was equipped with the old D-jetronic system. Expensive to fix, and touchy to adjust.

The later K-jetronic cars, with the cats underneath the bodies, are much easier to maintain.

 

[Slow Car Sport Mode]

I love the R107 body, like that red one.

The 1975 450SL belongs to a buddy. We spent a year taking it apart, working on engine, transmission, subframe mounts, front suspension, brakes, fuel system, interior and HVAC.

It was fun. He bought lunch and/or beer. I provided labor, space and tools. I reckon I saved him tens of thousands in farming the work out. He got his car back on the road.

I would not recommend a 1975-76 R107 however, as in those two years only, Mercedes integrated the cats into the exhaust manifold, causing the heat to roast the wiring, which caused issues, and the car was equipped with the old D-jetronic system. Expensive to fix, and touchy to adjust.

The later K-jetronic cars, with the cats underneath the bodies, are much easier to maintain.

My favorite SL is between those two…

Sure, convertible, maybe, why not. Not gaudy hardtop is fine too. Up to 2001/2002…

 

[TheLastWord]

$1,800 was the quote 12 years ago.

That’s part of how I ended up with the S600. It belonged to a buddy, who about choked when he was quoted that for service. He realized that he couldn’t keep paying the dealer for service.

Around here MB charges $200 - $225 per hour. So $1600 - 1800 for labor only. What do they charge for 24 plugs? Why is is it so hard and so long to change plugs? Coils have to come out, what else is removed?

 

[AutoMechanic]

Very clean engine for sure. I could not imagine owning a car with those expenses though. Good thing you know your parts guy.