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Discussion Starter #1 (Edited)
2 years ago a bough a 560sel 1990 model as i simply loved those cars (luxury power). 6 months later the waterpump failed. bought a new one and had it installed. The installer made mistake by not fitting the pulley properly on the crank shaft. the bolt came lose and damaged the crank shaft end (key & Key way) beyond repair. Found a second hand on and had it installed and the heads and valves done at the same time. on collection the car refused to iddle and by "pumping" up the mixture it would iddle but at 1800/2000 rpm. The repairer failed to get it right. I noted that you could disconnect the ICV valve, EHA unit, Temp sensor without any consequences. I checked the ICV by hot wiring it and indeed it stalls the engine immediately when you get it eventually running badly. I removed the whole metering unit with fuel distrubitor and noticed the black rubber booth did not seal properly on the trottle valve housing. Cleaned the metering unit, cleaned the trottle valve asembly, removed the fuel distrubitor and took out the control plunger to check it's free movement. Then put is all back with new gaskets, and sealed the booth on the trottle valve housing with silicon sealant. waited 24 hrs to have the silicon dry properly and tried to start it. it kicks in but then it still dies. As said above it looks like that the whole ECU unit and it sensors and valves are dead. I try to find info on the power source for the whole system Which I suspect to be fused but I do not know where.
Long story but has anyboddy any idea what I could do next to get this car back to it wonderfull running condition prior to the crank shaft trouble.
I sincerely believe that the 560SEL and SEC are probably the best cars Mercedes ever made in terms of durabillity, power and luxury.:mad:
 

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Might help to get clear on the model. There is no 1992 560SEL and there is no 1982 560SEL either.
 

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Discussion Starter #3 (Edited)
Thanks German Star. 1882 was an obvious typo. Even 1992, as you say, might be wrong as I had at that moment (And have right now) no docs for the car with me and I quessed the approx year. I believe however that in 1990 they still made them as mine was one of the last ones they made so lets say 1990. Nothwithstanding that I do not see you contributing anything towards a solution of the problems I was trying to discribe, which I was hoping for.
I m not a mechanic but I like to work on my cars myself as a hobby.
Tried a bit more last night. The trick I was advised on to set the rough mixture by turning the set screw in (3 mm Allen key) fully in and then 3 turns out did not work. I took out one injector and kept on adjusting the set screw till the injector started to spray. then the car would start but still iddle 1800 rpm. I then tried to get the iddling down by adjusting the mixture, which only partially works but when you then stop the engine it will not start again. I just try to discribe what I do so that people who realy know about these systems may tell me what I do wrong.
Another thaught; The garage removed the aircon compressor as the mounting bracket was apparently cracked. Has disconnecting the compressor anything to do with this high iddle. further question. Should the ICV react (closed or partially close) when you start from cold?
 

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1982 500SEL; 1987 Mazda B1600; 2001 Holden Vectra 2.6L
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As many on here will tell you there are lots of possibilities what you could have, maybe even more than one problem at once.

Try start at the simple things and work by process of elimination.

Start with vacuum leaks since thats what it sounds like, check your initial ignition timing is correct, check that the valve timing is correct, then start messing with the sensors last.

Let us know how you get on.
 

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Discussion Starter #5 (Edited)
Thanks Crusty rusty. As you can see I am new at this game and trying to work myself through it.
A. I taught about the timing and loosened the distubitor and turn it back and forward with no apparent result.
B. Vacuum sound logical and i have tried to take hoses of to see what it would do but also no apparent effect. I used "quick Start" spray all around the engine (inlet manifold gaskets, Metering boddy rubber booth connecting to the trottle valve, injectors, vacuum pipes) when it runs to see or it alters the rpm's as it get sucked in somewhere where it should not but no result either.
C. The trottle valve is fully closed (still on factory setting) when it runs 1800 RMP, where is the air going in?
D. Valve timing I do not know how to check. The guy who did the crank and heads is a Mercedes Benz Ex WorkShop Manager so I presume they get the valve timing right.
 

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1982 500SEL; 1987 Mazda B1600; 2001 Holden Vectra 2.6L
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With the distributor you may have to borrow or buy a timing light. Also check the spark plugs and leads.

For the valve timing you will need to set the crank at TDC and remove the valve covers, there should be a notch in a washer that is for the cam timing mark. It may be say half a tooth out if the chain is stretched but should be no more than that. I havent done a 560 myself so you may have to google that for pictures if you need more info.

The vacuum leak can be the hardest with the fan blowing the ether all round the place. I normally use the cans that come with an extension tube so it gets right in next to the cracks Im testing. The ICV might be stuck open, maybe try cleaning it out with carb cleaner.
 

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Discussion Starter #7
Hi guys,

Got the mix set so it runs and starts well (Hi revs - 1500). last night I pulled the small connection pipe between the two main pipes connecting the ICV to the metering unit and the auxiliary air pipes. the refs went down to 1000 instantly. Obviously now there is a "Air Intake" either towwards those tubes gouing to the injectors or into the metering unit housing. I am awaiting a new (2nd hand) ICV and ICU to arrive but I am still would like to get answer to the following question. When the ICU and ICV would work properly I imagine that the valve will close at start and then partly opens when the engine runs but it then simply restrict air flow betweeen the area below the baffle plate in the metering unit and those pipes going to entries next to the injectors but no "Outside" air is allowed in. Is that the whole idea? and is that ICV indeed supposed to be "Constant open" with the engine not running and contact off or is there something wrong with it. (as said above a get 2nd hand ones in any case)
Last but not least, can someboddy direct me to a test procedure (Diagram) which I can download for my 560sel 1991 (ICU number 006-545-84-32)
 
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