1990 560SEL M117 Starting Problem
Thread Starter
Junior Member
Joined: Aug 2008
Posts: 19
Likes: 0
From: Lewistown, PA
1990 560SEL
1990 560SEL M117 Starting Problem
I just finishing installing my rebuilt M117 and am having problems getting it to start without priming by pouring some gas into the intake. Once it starts I need to feather the throttle keeping above 2500RPM to keep it running. It runs a little rough at that speed but I haven't been able to set the timing yet (obvious). As soon as I stop feathering the throttle it will stall. Before trying to start the first time I installed a new fuel filter and flushed the lines by running the pumps. The flow rate is good according to the MB fuel pump test. I don't have the fitting to test the pressure at the pumps. The idle air valve is clean and worked before starting the rebuild.
Anybody have any ideas? Would a faulted idle controller cause this type of behavior? Anybody know if the upper and lower fuel dist. pressure tests are valid when the engine isn't running while running the fuel pumps?
Please help,
Nathan
Anybody have any ideas? Would a faulted idle controller cause this type of behavior? Anybody know if the upper and lower fuel dist. pressure tests are valid when the engine isn't running while running the fuel pumps?
Please help,
Nathan
Thread Starter
Junior Member
Joined: Aug 2008
Posts: 19
Likes: 0
From: Lewistown, PA
1990 560SEL
My solution
I dug into this and found that the upper / lower intake manifold o-rings were leaking...it was essential a vacuum leak. The only gaskets that I didn't replace during the rebuild, got replaced.
