How To: Mercedes Diesel Fuel Tank Strainer Cleaning/Replacement

W116, W123, W124, W126, W201

How to Maintain Your Mercedes-Benz Fuel System

As any Benz owner knows, keeping your vehicle in peak condition is key to maintaining its value and performance. That's why it's important to be proactive about your maintenance schedule, and know when it's time to replace or clean certain parts. In this post, we'll focus on the fuel system, specifically the fuel filters and tank strainer. We'll tell you how often these parts should be replaced or cleaned, and what signs to look out for that indicate they need attention.


Fuel Filters
Your Mercedes-Benz has two fuel filters: a spin-on style filter in the engine bay, and a small fuel pre-filter. These filters are responsible for catching any impurities that might be present in the fuel system. It's important to keep them clean and free of debris, so that your engine can run smoothly.

We recommend replacing the fuel filters every 20-30,000 miles, or every 2-3 years - whichever comes first. If you notice any losses in power or a rough idle, these could be signs that your fuel filters need attention.

Fuel Tank Strainer
The bottom of the fuel tank has a fuel tank strainer. This strainer is responsible for catching large particles that might be present in the fuel system. Over time, this strainer can become clogged with debris, which can lead to engine issues.

We recommend cleaning or replacing the fuel tank strainer every 90,000 miles - or sooner if necessary. If you notice hard starting or stalling, these could be signs that your strainer needs attention.

Keeping your Benz in top condition requires regular maintenance - and that includes paying attention to the fuel system. By replacing your fuel filters every 20-30K miles and cleaning or replacing your fuel tank strainer every 90K miles, you can help ensure that your vehicle runs smoothly for years to come.

Tools and Parts:

• 46MM or 1 and 13/16 Low Profile Socket(Custom Built)
• Vice grips 
• Fuel tank strainer or O-Ring(Clean/Replace)
• Fuel outlet hose(Inspect/Replace)
• Fuel storage container w/ Long Funnel
• Brake Cleaner

 

1. Drive the car till the tank is almost empty. It will make draining it much easier
2. Use vice grips to clamp the fuel outlet hose coming from the engine to avoid fuel spilling
3. Remove the fuel outlet hose & drain the fuel tank. A long funnel is helpful
4. Inspect the fuel outlet hose for cracking. Replace if necessary 
5. Use a modified socket to remove the fuel tank strainer
6. Inspect and clean the strainer with brake cleaner or install a new one
7. Reinstall the strainer with a new rubber o-ring
8. A very dirty strainer is often the sign of Algae in the fuel tank that can be removed by running Biocide in the tank

All the parts and tools you will need are available at the link below. 

https://www.lermscustoms.com/collections/tools/products/w123-fuel-tank-strainer

This kit and instructions fits the Following Models:

 

 Fuel Tank Strainer # 

124-470-01-06

Fuel Tank Strainer O-Ring # 

022-997-06-48

Fuel Tank Outlet Hose # 

116-470-14-75

Spin-On Filter # 

1-457-434-153

Pre Filter # 

0-450-904-077

 

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