RaceHorse

I'm glad to hear you have the ability, you will need it from time to time. The intercooler system is kind of a poorly design setup with no reservoir. Some people have added a small expansion tank since everytime you ever open the cover the fluid seems to be lower than it should.

Geraldius

That expansion tank sounds like a good idea.

Geraldius

Just finished with changing all the right bank plugs. 3 hour job. I managed to get the coil pack off without breaking it, but it didn't want to come off without a fight. The plugs on this side all looked very clean and barely used. I could just as well have left them alone.

The biggest single chunk of that time was on gapping the new plugs -- there's just so many of them. Next was probably on cleaning all the plug boots. Easy but tedious.

Other random maintenance completed: new cabin particulate and charcoal filters, and new engine intake air filters. Still have the oil change and brakes inspection to do. That will have to wait until next week when I can get it on the lift (wife's car is on there right now).

We drove the CL to South Carolina yesterday for a quick 'supply' run for the upcoming 4th of July holiday. About a 260 mile round trip. The car is running beautifully. I love driving this car! But oh, does it distort one's perception of speed...

principledchiro

LOL, on the open highway your CL65 will gap most new muscle. We lived in Wilmington NC for a few years (late 04 to late 06). Read up on my post "RaceHorse CL65 can either stop or start a heart". Enjoy your elegant and beastly CL65.

Geraldius

Thanks, I read that... it was entertaining.

Geraldius

Service B is now complete -- if a few days overdue. When I pulled the belly pan to drain the oil I was surprised to see it was completely oil-free. Dusty, but otherwise clean! A nice bonus for a used MB in my experience. (made me worry it had no oil in it! LOL). The entire underside and engine did not have a drop of fluid leakage or seepage anywhere! Not only that, but when I drained the oil I got a full 10 quarts out. Now I cannot tell when the oil was last changed, but I know that I had not added any in the 2500 miles since I bought it. And that includes hundreds of miles of high-speed driving. So oil consumption is virtually nill. We shall see at the next oil change...


Brake pads are at about 50%. Still serviceable but I think I'm going to go ahead and change them out anyway. Anyone have recommendations on pads other than the original MB parts?


Pic from the rear.

g60wall

You had to tap your plugs? The ngk come pre-gaped? What plugs did you use?

Geraldius

I used Denso Iridium Twin Tip IKT20TT 4702. Gapped to 0.7mm (0.027").

1Solo1

Beautifulcar! Looks very similar to one that Iwas too late inquiring on….started off at Orr Nissan (Louisiana) and eventuallymade its way to Texas (on eBay). I endedup purchasing one from Utah. Enjoy, she’shot!!

Geraldius

It is that very same car. I think Orr Nissan got it at auction as a bank repo.

g60wall

I had horrible experiences with different plugs. Destroying coil packs etc. go with ngk stock spec and they are the best for the coil packs. Is there a reason you picked that plug over stock other than price?

Geraldius

Price and availability. These were only $5.34 and I couldn't locate a source for the NGKs in the needed timeframe except from the dealer at about $20. Did you have problems with this specific Denso plug? These seem to be performing well for me so far.

Do your 'stock spec' replacement NGK plugs have the Mercedes logo on them?

1Solo1

Cool! Congrats on the purchase!.......I'm sure you'll enjoy it.

Geraldius

I mentioned before that my driver's side door soft close feature was broken. I got that fixed and documented my procedure here:
https://mbworld.org/forums/cl-class-...sm-repair.html

The car is still running great otherwise. Just completed a 500 mile round trip, Raleigh to Asheville and back. Nice run through the mountains. This car handles the hill climbs effortlessly at whatever speed you want to go, while most other cars are struggling.

My next plan is to replace the front brake pads. I've got a new set of Akebono Euro ceramic pads to go in. I hope they work well.

Geraldius

Lost another left-side ignition coil pack Sunday while loafing along at 45mph. Sudden total failure, same as last time.
I got a whole 1700 miles out of this one. The ignition voltage transformer checks out ok. A new coil pack replaced under MB parts warranty is now installed, and the car is running fine like nothing happened. Makes one feel like carrying a spare one in the trunk -- right next to the spare tire...

g60wall

Put ngk plugs in with the proper 1k ohms of resistance

ItalianJoe1

The entire pack shouldn't go out, there has to be a cause. I've lost coils under hard load, but for the whole thing to die out is very strange.

g60wall

Trust me please

ItalianJoe1

I'm assuming he's running the correct OEM plugs, but if not that can def be the issue. It really matters on this setup. More than any other car I've ever seen.

g60wall

I figured out the cause of this, normal plugs have. 5k ohms resistance the plugs designed for this car carry 1k ohms of resistance. So even if the threading and electrode size are the same the resistance is not correct

ItalianJoe1

Yeah even NGK shows two different part # for the v12, one is the "OEM" with the correct resistance and spec, the other is theoretically the same but it's the one you say with incorrect resistance, that fries coils.

It still will pop individual coils though, not all 12 at once.

g60wall

Make sure the ground is tight and the bolt isn't threaded on the coolpack that is affected

Geraldius

Thanks guys. The Densos I have in there now are 5K resistance. The first coil pack failure was with the Mercedes branded NGKs and it failed in the same manner. Interestingly, the original Mercedes NGKs that I removed are 2K (measured). I wonder if they changed the specification for this plug?

I went ahead and ordered a full set of NGK 5648 (IFR6q-G) plugs. They are stated to be 1K resistance in the specifications. I'm not convinced for certain if they will help, but shouldn't hurt.

I'm inclined to believe that the failures are temperature related. Both times the failures happened while driving at slow speeds for several miles on very hot days. It could be that low airflow through the already cramped engine compartment, with AC on, leads to heat build up in the coil packs. Both times the failure temporarily went away after the car cooled for a little while, but then became permanent when the car cooled completely.

g60wall

I was reading that the voltage transformer is the cause when losing a whole bank. About the heat, while it is possible I stop blaming the heat for any failures. The car was designed to be that hot under the hood and everything. Was taken into consideration when building it. The heat does though effect the longevity of certain components that I agree on. Also make sure all 4 map sensor are good, there very important because the car calculates spark off the measurements of air density. Another thing to check is weeping valve cover gaskets! Also for the other coil pack get new insulators to ensure proper seating

to keep your eye on the prize here's a pull in my tuned s65

https://youtu.be/TavwxhZ83SU

Geraldius

Three strikes and you're out or third time's a charm?
Well... The ignition cut out on me again with the new coil pack during a test drive after only about 20 miles.

Two times might be a coincidence, right? Three times and there's got to be something else going on!

This time I decided it's got to be the voltage converter transformer. It was the only other thing that makes sense. After letting the car cool off for a couple of hours the ignition came back. I took it out again and it failed within about 5 miles this time. So I picked up a new transformer from the dealership and it fixed the ignition with the same coil pack still in. Swapped back to the original transformer and the problem follows it. That's pretty conclusive.

The strange thing is that the previous coil pack swaps were always followed by the ignition working again. I can only conclude that the problem with the voltage converter transformer is intermittent and strongly affected by temperature. There is no visible damage like burned components under the lid. My best guess is that there is an intermittent bad connection in it like a cracked solder joint or cracked circuit board trace that opens and closes when it heats and cools.

Getting this mysery solved is going to give me a lot more confidence in taking the car out on longer trips. You guys that have a CL probably get this; I like driving this car so much that I get a bit depressed when I can't take it for a drive. It's not my daily driver -- I don't want it to be. It's more like something I treat myself to just for the pleasure, and I find myself making up excuses to take it out for a spin. I've got several special interest and collector cars and motorcycles, and they all get their turn being driven on occasion. But I start jonesing if I can't drive the CL at least once a week.