Starting with new injectors

[dwilli3038]

Hello All,
Last year I got the 230SL running but very poorly. I found a very ruty gas tank. Due to a broken foot, I was unable to deal with the problem. Now I have a new tank, new fuel lines from the tank to the injector pump. I tested my injectors...they poped at 20PSI, so I now have 6 new injectors. When I tried to start it it took forever to get the fuel up to the injectors. The car would try to run when the cold start solenoid was energized but would then not continue to run. I ran out of time and battery charge so I stopped.
I suspect I have too much air for the fule as it was most likely adjusted fr the weak injectors. Before I start on it saturday any advice?

Daryl
'64 230 SL
Serial # 508

[rwmastel]

With the old injectors opening under low pressure, I don't think that that indicates you were getting more fuel with the old injectors, but that the spray pattern would be poor.  This is just a guess, any comments?

With a new main fuel line, injectors, and a cleaned out tank, I would also assume that you introduced lots of air into the system.  From what I recall, you simply need to crank the system and let it push the air out naturally.  Perhaps you could take the fuel lines off the ends of the injectors, disconnect the coil or distributor (or somehow prevent the car from starting), and let the starter crank the engine and fuel system until you see fuel coming out of the lines at the injectors.  Then put everything back and see if it starts and runs.  Adjust cold-running and warm-running fuel/air mixtures as needed.  This would also be a good time to test your CSV (cold start valve) on the intake manifold by removing the test bolt and seeing if fuel continues to flow after 2 seconds of engine operation.

Everyone: does this sound reasonable?

Rodd
Powell, Ohio, USA
1966 230SL, Euro, Auto, Leather, both  tops
1994 E420

[George Davis]

Well, for the brave and/or foolish, here's a starting trick.  I recall Joe Alexander writing that when first trying to start an engine with the injector lines empty, you'll get a "false start" from the CSV, but after that you just have to crank and crank and crank until it fires.  Well, I thinks, if it starts momemtarily on the CSV, will it will run long enough to fill the injector lines on the CSV?  The answer is yes.  I connected a jumper wire from the CSV terminal directly to the battery positive, then hopped in the car and cranked.  It fired up in a couple of seconds and idled just like normal (until like a dope I pushed on the gas pedal which killed it, so don't do that).  Restarted it right away, it idled well until the injector lines were full and then, being too rich, it started idling badly.  Pulled the jumper wire off, it settled down and no overly long cranking required.  Use this trick at your own discretion!

George Davis
'69 280 SL Euro manual

[Naj ✝︎]

If its just air in the injector lines, you could crack them open a turn or two and crank till you get fuel leaking out. Then retighten lines and go.
With new injectors, its probably more difficult to push the air out as the air compresses every time the inj pumps and then expands again as pressure is released.
If it starts with George's trick, you could bleed each line after starting the engine.
good luck Saturday,
naj

65 230SL
68 280SL