Why won't it start?

[ctaylor738]

Hello, your 280SE Pagoda wannabe again.

A brief history.  1972 280SE, stored two years.  Replaced fuel filter, cleaned tank, new plugs, fresh fuel, cleaned injectors.  Started easily and was running OK.  Then it began to sputter going up hills, and gradually got worse.  Then it would start and run and die, but start again after it sat. Then it got harder to start, finally not starting at all after a 30 second crank.

Knowing that I still had a rusty tank, I pulled it and had it cleaned and coated.  With the tank out, I pulled the electric pump and discovered a completely crudded up filter which I cleaned.  Tonight I put everything back together, thinking that between the pump filter and the tank, I had the fuel supply problem nailed.

So I turned the key, confident of a quick start and better running.

But no start - not even a pop.

There is flow to die for now from the tank.  The electric pump is running.  I loosened the fitting at the FI pump and, while I did not do a pressure check, there is certainly plenty of gas getting to the FI pump.  After cranking and jumping the cold start valve, the plugs are bone dry.  I unscrewed the line to #4 and cranked with the throttle wide open.  Not a drop of gas from the line.

I would greatly appreciate some direction as to where to go next.

Thanks as always,

Chuck Taylor
107 Addict
Falls Church VA

[George Des]

Chuck,

Just some thoughts  and at the risk of stating the obvious, it looks like you've at least narrowed this issue down to the point between the FI pump and the injectors. Perhaps the FI pump has become crudded up with the bits and pieces that were flowing through the fuel system prior to the fuel tank and pump being cleaned. Could also be the lines themselves between the FI pump and the injectors. These have been known to rust up from the inside out. It may be time to either pull the fuel injector pump for a rebuild or thorough purging of it and the FI lines.


George Des

[ctaylor738]

Just to close this out.

I found that in addition to no fuel, no spark - zero voltage at the coil.  So I ended up replacing the ballast resistors with a spare set and got spark back.  I also bled the fuel system at the CSV.  Started easily and seems to run fine with its improved fuel supply.

Chuck Taylor
107 Addict
Falls Church VA

[Chad]

I would not have guessed that as the final solution based upon the last issue, dry cylinders.
Anyway, it sounds like you've done a good deal of maintenance on the fuel supply system that should provide for much enjoyment in the future.

When are you going to get yourself a w113 and post the pictures?





1967 230SL (Manual, rustless driver)

[ctaylor738]

Well, the right one needs to come along.  Ideally it would be an unrusted 250SL survivor that had suffered some major mechanical meltdown, or in pieces from an abandoned restoration.

Chuck Taylor
107 Addict
Falls Church VA

[norton]

Chuck My guess is that coating the fuel tank may have plugged the "flower pot" Here's a link to one of Joe's excellent post's on fuel tanks. http://sl113.org/forums/index.php?topic=1712,tank,tour

Mike Halleck
Chesterfield Mi
71 280SL
68 250SL (parts car)
94 E320 Coupe