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'82 Euro 500SEL, '85 Euro 500SEC AMG WB Cabriolet,'86 Euro 500SEC RUF
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Discussion Starter · #1 ·
I have searched on this forum for a definitive answer and there have been none come up.:surrender:

It starts and runs for a second or so, then quits. I'm positive it is in the mixture screw. I was turning it bit by bit CCW and it died. Feels like it isn't getting fuel or is flooded, but it does start.
I checked the fuel line in and out of the FD and the pump is working great, filled the bottom third of a 1 liter soda bottle very shortly, a second or so. So the pump works and the filter isn't clogged.

I have switched EZL's about and FPR's and it's the same thing. Switched ICU's too.

I fear I have messed up the Mixture ratio while trying to lean out the car.
Is there any PDF's telling how to center the mixture screw so at least I can get the car started.

It is a screw through a spring so in reality it will tighten to a stop at some point.

What I need is the PDF's on this or someone has fixed this problem to chime in with some info.

I promise NEVER to do this stupid thing again, but I need help.:surrender:
 

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300se, 560sel
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486 Posts
If you can find a shop and ask them to adjust the "c/o mixture" or ask that the "lambda" be set. They should be able to help.

I had adjusted my EHA and then took it to a guy who had a ratio tester and had it adjusted.

I have been trying to locate one for myself, but never seem to get a hold of one. I think there are digital ones out there as well. A link to a "DIY" via voltmeter is on our site.
 

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R.I.P. Never Forgotten
1983-2007 MB's
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8,023 Posts
The question is.... IS there a stop in the FD adjustment screw? Or if you go too far does it separate the screw from the linkage adjuster?

Have you tried backing out CW one full turn, trying the start afterwards?

How does the CIS plate look in alignment with the throttle body opening? Are there gaps that let air in as it sits now?
 

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'82 Euro 500SEL, '85 Euro 500SEC AMG WB Cabriolet,'86 Euro 500SEC RUF
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9,498 Posts
Discussion Starter · #4 ·
The metering disc appears to be setting just above the convex edge(Venturi) on the 500 SEC Euro this does not have the venturi wall thickenss that the NA 560's have. On the 560's it vee's down to the venturi wall and that wall is about 1/16 " in depth.
The 560's seem to be sitting with the metering disc's at an angle ti the venturi wall.
On the 500, the Venturi wall is nothing but an edge, the body vee's down to the edge. The metering disc is sitting alomost flush with the edge, but just a hair high.

I remember turning the screw a couple of bits CW and it made no difference in the running of the car, then I turned back to center then turned bit by bit CCW. It startd to die once or twice and I returned the last bit I did. I restarted the car and was getting ready to back the screw off a bit when it died. It has not kept running since.

BTW I'm not out of gas either.
 

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CH4S Admin , Outstanding Contributor
1985 500SEC, 1991 190E 2.6.
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48,246 Posts
I have searched on this forum for a definitive answer and there have been none come up.:surrender:

It starts and runs for a second or so, then quits. I'm positive it is in the mixture screw. I was turning it bit by bit CCW and it died. Feels like it isn't getting fuel or is flooded, but it does start.
I checked the fuel line in and out of the FD and the pump is working great, filled the bottom third of a 1 liter soda bottle very shortly, a second or so. So the pump works and the filter isn't clogged.

I have switched EZL's about and FPR's and it's the same thing. Switched ICU's too.

I fear I have messed up the Mixture ratio while trying to lean out the car.
Is there any PDF's telling how to center the mixture screw so at least I can get the car started.

It is a screw through a spring so in reality it will tighten to a stop at some point.

What I need is the PDF's on this or someone has fixed this problem to chime in with some info.

I promise NEVER to do this stupid thing again, but I need help.:surrender:
You should be able to find all the pdf with a forum search Charlie. There are a few mistakes in the index. For example, if you don't find a pdf with the correct 07.3-105, look under 073-105 and so on.
Perhaps this helps:
 

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1985 380SE
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You just have to play with it. Do it 1/4 turn at a time. You say it starts then dies? Does giving it some throttle as you crank it keep it going? If so, you're lean (or WAY rich, which doesn't sound to be possible).
 

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'82 Euro 500SEL, '85 Euro 500SEC AMG WB Cabriolet,'86 Euro 500SEC RUF
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Discussion Starter · #7 ·
Nope! won't stay running even with my foot on the throttle.
I think I'll try the one bit at a time from way lean. This is definitely a learning experience.
I have learned : Don't screw with the Mixture, let a professional do it..
 

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1985 380SE
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No point in taking it way lean. Just lean it 1/4 of a turn at a time. Also, you sure your battery isn't dead?

If you have someone who can help you there is a quick trick to getting it - take the air cleaner off - while one person cranks it the other person pushes lightly on the metering plate. If that lets it run you're lean, if not you're rich. This way you know when you've overshot it.
 

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'82 Euro 500SEL, '85 Euro 500SEC AMG WB Cabriolet,'86 Euro 500SEC RUF
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Discussion Starter · #9 ·
Update:
Marlinspike, you had a great tip.

Battery is good. I was able to charge it up some this afternoon too.


No one was here today, so I opened the air metering disc a bit with a small torx screwdriver to keep the plate down and she started and ran. I was able to get her close twice this afternoon. First time I was able to keep her running without the screwdriver or the plate pushed down. Took some fiddling with, one hand on the disc to keep it running and one turning the screw bit by bit with the other hand. Idle was high 1200-1500RPM and as it was lean I enriched it bit by bit and got the idle down to 1000RPM. I could rev the engine and not kill it. I shut it off and it started and ran on it's own, but at 1000RPM. I tried to drop the idle to 750RPM and I killed it. It would not start on it's own or with the torx in place. (too rich).
I turned it lean enough to start with the torx opening the metering plate again she started and ran again. I was able to keep it running again by the metering screw (same process as above)but the idle was again 1200-1500 RPM. I turned the screw and got the idle down to about 1000RPM. Shut it down and was able to start it again and it ran. Once again I adjusted the mixture bit by bit to drop the idle, but it died.
Tomorrow I'll go back lean, start it and get it back to the 1000RPM

The next time the idle is at 1000RPM I'll check the idle rod and see if I'm fine at 1000RPM and just need to fine tune the idle. I notice that the roller is not in the bottom of the arc in the arc lever that controls the Bowden cable, so the mechanical idle settings may be off some.

One other thing with the idle. I have two ICM's and one runs at about 500RPM at idle and the other is 1000RPM(that one is in the car now). That is why I think the 1000RPM mixture setting is where it should be and the mechanical idle adjustments may be out of whack. I don't know why one idle the car at 500RPM and the other at 1000RPM unless one is getting weak.

Thanks for your tip. It made my day. I'm soooo close to getting it right now.
 

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1985 380SE
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1,293 Posts
When it's cold no matter what idle control unit (as opposed to idle control valve) you have in there it should idle the same - cold engine the valve should be open, the same as if you took the two prong plug off the valve. As far as why your idle is high, is that on a warm or cold engine? Anyways, the mixture screw isn't really an idle screw, it just affects idle by changing the mixture.

Here's a quick and dirty way to know when the mixture screw is set right:
set the mixture
give it some throttle blips to make sure the plate is seated
push down on your plate with your hand - if this makes the engine rev a bit you're too lean, if it bogs it down your too rich (btw, no matter how lean you are pushing it down enough will bog it down). You're just right when pushing the plate every so slightly down does nothing.
 

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'82 Euro 500SEL, '85 Euro 500SEC AMG WB Cabriolet,'86 Euro 500SEC RUF
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Discussion Starter · #11 · (Edited)
One more tip for the books. Funny, I noticed that same thing this afternoon when it was running the best, a slight downward pressure did nothing. That tells me I am really close.

I'll get it back to that point, then check the mechanical idle parts. I know already that the Arc plate is a bit out of sync with where the idle rod roller should set at idle. Mine is about 1/8" up the arc. It also looks like that corresponds to the adjustment of the Bowden Cable flat connector that has the set screw set about that distance closer to the cable that it was at one time due to the looks of where the set screw was.

Thanks again for your help.
 

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1985 380SE
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Set the mixture to where pressing on the plate does nothing and see what your idle is on a fully warmed up engine...if it's 1500rpm I bet your problem is simply the idle control unit. If it's 1000rpm I would look for something else, like a vaccum leak. I would be surprised if it were the throttle linkage, but take a photo of it. The bowden cable adjustment would have no impact on the idle.
 

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'82 Euro 500SEL, '85 Euro 500SEC AMG WB Cabriolet,'86 Euro 500SEC RUF
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Discussion Starter · #13 ·
The Bluebird starts and runs!
Not optimal, but as close as it was before I messed with it.
Idle Control Unit in the car idled at about 1350 RPM. Swapped it for the old one and it's back to about 600 RPM at idle , warm in park. Not exactly where I want it, but she starts and I don't see any black smoke when I rev it up.
I'll get it into My Indy as soon as I get the headlights(Bezels)/wiper motors and grille back in it. They are being painted along with the Wiper arms. Body color.

Marlinspike,
I could not have, nor would I have tried, without your hints. I owe you a cold one or two.
How close are you to Lumberton, Whiteville area? Reason I ask, is I'll be there sometime in April or May to see my Sis and Nephew and Grand Nephew.
 

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1985 380SE
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I'm actually no longer in NC...I'll update it one day.

You'll need to look for vacuum leaks (in D, at idle, A/C off, foot on the brake, where is your economy needle? should be pegged to the left), but given that you're only a few rpm low at idle, I wonder if you just have an excess of gunk in your idle control valve. Might be worth cleaning it out with some brake cleaner (if not using Wurth brake cleaner, be very careful with this stuff, most of the brake cleaner on the market is very bad for you...and paint).
 

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380 sel 1982
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31 Posts
hey help me now i have 82 380sel bought from neighbor hasnt ran for 5 years!push it home from next doors took off the gas lines blew them out neighbor said he bought a new fuel pump and cleaned and put something in the tank to recoat it .well found out fuel pump was bad any way replaced it check pressure (outlet volume) ok cranked it.Me not realy ever mess with cis(just read about system)i kept pushing down on the flap when it wasnt running hearing a strange noise (later finding out it was fuel)i finaly hydrolock it up! i have had this problem on other cars so lucky i knew it!but at first i did think that i should have squirted some oil in the cylinders first and thought it locked up. Anyway i took all the plugs out and cranked the motor.Gas shot every where but i thought that it came out of number 3 cly more but i wasn't for sure.i took my air compresure and blew out cylinders and the i thought that i could hook it up directy to the number 3 injector to see if it was stuck open.I didnt have much pressur about 40 pounds but it didn't leak i cross reference with the injector next to it to figure out some kind of comparison it didnt leak also so i put it back together.and let it sit for the night.In the morning (day 2)i had father in law crack it ,still nothing,I then started to mess around with the flap,and the wala the ran only on high prms it ran good until i stop openning up the flap just a little also it had no response so i warmed it up and still no idle.i ohm the wur and it was in spec? no vaccum line bad car is in realy good shape i figure i shouldn't mess with the adj screws since they have never been touch before. NOW what?
 

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1982 280 se aut. ecc. - sold
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Somehow I don't think that asking the same question in 10+ different threads is gonna do you much good.
The Fuel-Air ratio is set by a 3mm hex in the screw on the FD.
Trial and error is a bad way to adjust. Measuring the CO (1.5 +/- 1 % IIRC) is the right way.

gr J
 

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'82 Euro 500SEL, '85 Euro 500SEC AMG WB Cabriolet,'86 Euro 500SEC RUF
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Discussion Starter · #19 ·
KK,
Please sort out your questions and give us a chance to help you.
Do some proper sentence structure and punctuation so we can keep up with what you are asking.
Your post ran both together and apart and in several directions.
I for one, found it very hard to follow.
Questions listed 1 at a time might garner some help.
 

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380 sel 1982
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31 Posts
you got to be kidding me ! Forget it i'll get a book this forum is for guys that worry about grammer and bench racing and something to do . what a week of waste i could have figured it out my self by now get me the fuck out of here weirdo sigh-n- off
 
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