Replacing Injectors (M103) DIY?
 

Hello,

I have limited technical experience with the engine on my 300SE. I have serviced the car myself (plugs, fluids, filters).

How difficult is it to replace the injectors?

I have a feeling this may be the cause of my on going problems, and I'd like to do the job myself if possible.

Thanks

This isn't a difficult job at all. Just be careful not to do it with a HOT engine. Gas will come out of the lines so keep rags handy.
Make sure to get new seals for the injectors AND either new insulators or at least new seals for the insulators.

Thanks Doc!

I'll get the parts ordered, hopfuly this will help towards solving my problems!!

Thanks again

Try cracking loose fittings at fuel distributor slightly and tapping on banjo fittings ith wrench if you see black sludge come out do this at all six fittings and see if your problem is resolved, thsi may also indicate that you need new fuel filter. Replacing injector end is easy and not that pricey if needed.

I'll do that, thanks Matt. :)

Make sure you use the type of wrench that grabs more than two sides of the fuel lines. I think it's called a flare wrench in the US. Those fuel lines will be tight and it will be very easy to round the corners of the nuts.

Sixto
91 300SE
81 300SD

Take Sixto's advice and be sure to use a flare wrench or you might end up im more trouble if you round the edges, then it's nearly impossible to get them off.

Good Luck:D

I tried posting one of my threads on the issue . If it does not take you there, let me know.
I found the most difficult part of the job by far, was getting the right parts...
As I've written before - MB has changed the seals and holders for the injectors on these cars very often.
Perhaps every year. Once you have the parts it is very straight forward. Good Luck.

http://www.peachparts.com/shopforum/tech-help/28432-mystery-techs.html

What exactly is a flare wrench and which ones will I need for an M116 injector replacement? If the injectors are dirty, what about all the fuel lines? The ones on top of the motor and the ones running from the gas tanks...can/should they be replaced as well?

A flare wrench is like a box wrench with one corner missing so you can slip it over a tube such as a fuel line. It allows you to grip more of a nut that you could with an open wrench.

FYI, Diesel fittings don't get as tight over time as gasoline fittings.

Fuel injectors have very precise orifices to cotrol flow and spray pattern and thus are a lot more sensitive to contaminants. Fuel lines are a lot less sensitive and can be cleaned by blowing air through them in most cases.

Sixto
91 300SE
87 300SDL
81 300SD