Saturday, January 01, 2011

Bleeding A Diesel Fuel System - Mercedes MBE 900 Diesel Engine

Here's a short video on bleeding the fuel lines on a Mercedes MBE 900 diesel engine. I'm using a tool made by Kent Moore with quick couplers that makes this a simple process. In 2006 we received 6 of these engines that didn't come with these couplers and at the same time the fuel sender wasn't accurate. There is a technical service bulletin that explains how to test the fuel tank sender from the OEM (Thomas Bus) or the operator will notice the fuel gauge is off track.

It was no surprise when we had a few incidents of buses running out of fuel. Back then all we could do was crank over the engine and crack one of the fuel lines or lightly pressurize the fuel tank to get the engine fuel system bled properly. Eventually we ordered the bleeding coupler kits and improvised a steel tank and hose slightly pressurizing it with shop air which worked great, but a little crude.

The Kent Moore J-47912 tool was the answer, sometimes it pays to give the fuel system a quick bleed after replacing fuel filters during a service.


Trade Schools said...

Great tip and concise video on bleeding the fuel lines.

bushmechanic said...

I use a primmer bulb from an outboard motor fuel line and have the lines long enough to reach the fuel tank plus it's a manual operation so great when out in the field.