Tag: m113k

Mercedes CLS55 AMG W219, New Serpentine Belt Tensioner

What do you do when you have a noisy serpentine belt tensioner? You replace it with a new one off course! Never skip an opportunity to buy new shiny parts 🙂

I was able to find a Trucktec Automotive tensioner for the m113k engine, which has a steel pulley instead of the known-to-fail plastic pulley. It’s an easy DIY task, the most time is spent on removing parts to get access to the tensioner.

Trucktec Automotive serpentine belt tensioner with steel pulley

Trucktec Automotive serpentine belt tensioner vs OE Mercedes Benz serpentine belt tensioner

New serpentine belt tensioner in place!



Mercedes CLS55 AMG W219, Scored An Upgrade Intercooler / Heat Exchanger

Was able to order an upgrade intercooler / heat exchanger for a very reasonable price. You will have to resort to US import, meaning higher costs.

They are very hard to get in the Netherlands for a good price, so happy days! It’s only a matter of finding time as it should be a pretty straightforward installation.




Mercedes CLS55 AMG W219, Upgrading To The Gates HD Fleetrunner Micro-V K080510HD 8PK1294 Supercharger Belt

It was apparent that the best in Supercharger belt would be the very popular green “Gates HD” belt, but it seems there is an even better one (more on that later).

When I ordered this belt, at the moment I thought this was the best that Gates had to offer. Its very popular as an upgrade belt and you will see it being used on many M113k engines (stock & tuned).

This belt should prevent slippage (meaning lost power) and will last a long time.

Partnr: Gates HD Fleetrunner Micro-V K080510HD 8PK1294

I have a stock supercharger pulley, so 1294mm is the correct belt length.




Mercedes CLS55 AMG W219, Replacing The Old SAI Hoses

Decided to replace the 2 old Secondary Air Injection (SAI) hoses on the front of the big V8 M113k engine. As I pulled them of, they started to deteriorate, so I was just in time. The SAI system helps the catalysts heat up faster in a cold start situation.

Partnr 1132381082
Partnr 1132381082
Old vs New SAI hose
Rubber bung under the SAI hose
New SAI hose in place
Old SAI hose (drivers side)
Old & new SAI hose (drivers side)
Result! Progress!
Just in time



Mercedes CLS55 AMG W219, Temporary Fix For The Oil Filler Neck

Had to apply a temporary fix for the oil filler neck, as it’s still leaking a bit (more like sweating). Used silicone sealant as a temporary measure. I will probably replace the filler neck somewhere next year.




Mercedes CLS55 AMG W219, Heatwrapping The Intake Tubes

A mod which has been tested on MBworld already, heatwrapping the intake tubes to keep as much heat out of them as possible. I had white heatwrap lying around, so I used that 🙂

Small supporting mod and a very easy DIY.

Work in progress



Mercedes CLS55 AMG W219, Leaking Rocker Cover Gasket (Again)

Last time I will be using gaskets from Febi Bilstein as the rocker cover started leaking again around cilinder 4. Replaced it with a Viktor Reinz gasket. If it will leak again, I will buy them from the Mercedes dealer.

Leak from cilinder 4 onto the exhaust manifold
Cleaned surfaces before gasket installation
New gasket in place



Mercedes CLS55 AMG W219, Replacing The Engine Mounts With Meyle Mounts

As part of further preventative maintenance, I replaced both the engine mounts with fresh new Meyle engine mounts. Unfortunately no HD version available. Next time I will probably replace them with Mercedes Black Series mounts, as these are a popular upgrade.

It’s highly recommended to replace them, as it makes a major difference!

Location of the engine mount (another one on the other side of the engine)
New mounts with the covers
Meyle (new) on the left and old on the right. I almost thought that I ordered the wrong ones as there was a clear height difference. But they sag over time, so that is to be expected.
Its highly recommended to have this tool ready as this makes it a lot easier to undo the top nut!



Mercedes CLS55 AMG W219, Servicing The Supercharger Oil

One of the most common overlooked service items, is replacing the supercharger oil. The gears of the supercharger spin very fast and need proper lubrication and cooling. Because it spins so fast, it requires a special type of oil: Mobil Jet Oil II (Synthetic Jet Engine Oil).

This oil is not that widely available to customers and also not very cheap. I used a 150ml syringe with some hose to extract the oil and fill it up again. It holds 150ml maximum, but you can never get all the oil out unless you remove the supercharger. I removed about 130ml, and put back the same amount in fresh oil.

Extracting the old oil
Used a plastic containter to hold the oil in, which makes it a lot easier



Mercedes CLS55 AMG W219, Some Statistics

Someone asked me on a forum how many kilometers per litre the CLS55 does and I was happy to share that information with them. Yes it’s a big engine with a lot of power, but when you treat it gently it can be quite economical for it’s size.

I achieved a respectable 1:8.5 over 155km (mostly highway) with cruising speeds around 120km/u. Also the fuel gauge indicated a half tank when I had already driven 350km’s, which suprised me!

I love the white gauges in the black dashboard 🙂