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Discussion Starter #1
First things first... Hello Everyone!
Been reading the forum for about a month now, been very informative thus far. About a month ago I came across a deal on craigslist for my father that I couldnt pass up. 1974 450SLC $500. Basically the car was at a dealership in Indy. It was the owners car, the brakes went out so he parked it and started driving a newer model. It sat for about a year or so and people started stealing items off it. They could no longer get it to run so they listed on craigslist as a parts car. Well after a little tinkering, new battery, new fuel pump, and some repaired lines car runs and moves under its own power.

The biggest problem I am having now is it is almost like it is running with the choke on. Keeps fouling plugs due to having to much fuel dumped and cant burn it off fast enough. New plugs and wires a week ago, same thing, so I went on step hotter on the plugs, same thing. Is their a way to fix this, am I missing something somewhere. So close yet still so far.

Need to get this up and going ASAP so my father has a way back and forth to the Dr. Going in for appointments and stuff due to cancer. Any help would be wonderful. Thx in advance!!
 

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'80 450SLC Afro RHD Ikonengold
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2,900 Posts
Welcome to the forum. Yo'll find a lot of good advises and plenty a less than good ones but you will be able to get anything fixed.

The model/year info of your car in the initial post helps other guys undestand what car you talk about but same info in the profile will attract more people responding. It takes a few minutes only, really.


Your car has D-Jetronik and is one of the first electronic controled injection system.
Until someone with experience with your type of injection arrives, here are a few universal tips:
There is a control knob to adjust amount of fuel squirted (footwell on the right under the lid) but before you do that you should inspect a lot of things like to check for vacuum leaks, run some injector cleaner and maybe check that your ignition is up to specs (bad burning will give impression of reach mixture).

<---- Fill in your profile like this

You could get a cheap W107 CD service manual library (eBay etc.) Not the best tool but good for starters.
 

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R/C107 Moderator
1986 560SL: '84 500SL: '84 280SL 5 speed: other 107s
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32,347 Posts
Info was in the inital post

Other than that, i had tried your suggestions... But thanks for the help
Is that your final answer?

Djenka18 welcomed you and asked what we asked of all new members. Fill in your profile.
 

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Premium Member
1986 560SL with M120 V12 Engine, 1988 560SL Stock
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10,209 Posts
Welcome to the forum and good luck with this car. For any car that sat for time the first thing I always try is a bottle of Techron injection cleaner. It really does work.

You say its getting too much fuel. Are all 8 plugs fouling or just one. I forgot if d-jet systems uses a cold start injector. In any case you have a set of points in the distributor below the ignition points that control injector firing. These are a trouble area. Cleaning these points with Trichlorethelene if you can still get it or today's equivalent electrical contact cleaner would be a good start if the Techron doesn't work.
 

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1973 450 SLC
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124 Posts
I would question the ignition timing, centrifical advance, the vaccum connections to the advance and the retard function. RTF to understand the timing of a mercedes and check the cars timing. I would almost bet if the timing was advanced the car would feel like a rocket in comparrison. The Master of the D-Jet checks his timing at 3000 rpm. There is a great post about timing on this board...basically an old car is hard to time and old parts don't work as good as new. This MAY require the timing to be advanced more than the book. When I find it I will note it for you.

Points require the dwell to be set which is critical to the car. All sorts of issues can throw off the dwell. Spend $85 and get electronic ignition it eliminates those issues. I will send a note

Go to harbor freight buy a $9.00 Engine Oil Pressure Tester Item # 92687 to measure the fuel pressure. I cut the end off and clamped a tee with short piece of 1/4" hose. There is a gas line hose in the front of the engine to test the pressure. Test for gas leaks by turning the ignition to "On". Fix and verify no leaks before starting the car.
The Master who has a Smart car for a golf cart, is trying to get 36 holes in before dark will be by shortly, recommends 30 lbs, except summer 32 lbs. My Grace SLiCk has 25 lbs at ignition "on" and 30-32 lbs when engine is running (due to the voltage difference). Fuel pressure is a big deal check the pressure and adjust it to around 30 lbs. After stopping the engine note for future reference how long it took the fuel pressure to bleed down to 20 or 25 lbs. When I bought my car it tested at 17 lbs (I cannot help but think people thought reducing the fuel pressure increased gas mileage).

Change the fuel filter, use techron, and run the car even if it is at idle in the driveway while you watch the ball game.

The next part is going to hurt. Vaccum leaks can be traced to every problem known to man or mercedes. There is a thread at the top of the forum with an encyclopedia of knowledge or the 10-100 VIP items to fix (the rest don't matter) which has a wonderful Vaccum section.

These guys know a lot thru personal experience in this and their previous life. They can be funny and some of us can't read or spell so pictures help. It is an adverse reaction from the brain scan before entrance in the witness protection program. They can really help you...just like the little lady down the street with the funny hat and a dozen rescued dogs and cats..they want to rescue every 107... with out wearing the hat.
 

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R/C107 Moderator
1986 560SL: '84 500SL: '84 280SL 5 speed: other 107s
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32,347 Posts
Since you have the 107 CD the Haynes Manual also has information you can use..
 

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Registered
1973 450 SLC
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124 Posts
I would question the ignition timing, centrifical advance, the vaccum connections to the advance and the retard function. RTF to understand the timing of a mercedes and check the cars timing. I would almost bet if the timing was advanced the car would feel like a rocket in comparrison. The Master of the D-Jet checks his timing at 3000 rpm. There is a great post about timing on this board...basically an old car is hard to time and old parts don't work as good as new. This MAY require the timing to be advanced more than the book. When I find it I will note it for you.

This is not the post but a similar post
http://www.benzworld.org/forums/r-c107-sl-slc-class/1373776-adjusting-timing.html

Points require the dwell to be set which is critical to the car. All sorts of issues can throw off the dwell. Spend $85 and get electronic ignition it eliminates those issues. I will send a note

Here is the note

http://www.benzworld.org/forums/r-c107-sl-slc-class/1518076-74-450sl-ecu-2.html


Go to harbor freight buy a $9.00 Engine Oil Pressure Tester Item # 92687 to measure the fuel pressure. I cut the end off and clamped a tee with short piece of 1/4" hose. There is a gas line hose in the front of the engine to test the pressure. Test for gas leaks by turning the ignition to "On". Fix and verify no leaks before starting the car.
The Master who has a Smart car for a golf cart, is trying to get 36 holes in before dark will be by shortly, recommends 30 lbs, except summer 32 lbs. My Grace SLiCk has 25 lbs at ignition "on" and 30-32 lbs when engine is running (due to the voltage difference). Fuel pressure is a big deal check the pressure and adjust it to around 30 lbs. After stopping the engine note for future reference how long it took the fuel pressure to bleed down to 20 or 25 lbs. When I bought my car it tested at 17 lbs (I cannot help but think people thought reducing the fuel pressure increased gas mileage).

Change the fuel filter, use techron, and run the car even if it is at idle in the driveway while you watch the ball game.

The next part is going to hurt. Vaccum leaks can be traced to every problem known to man or mercedes. There is a thread at the top of the forum with an encyclopedia of knowledge or the 10-100 VIP items to fix (the rest don't matter) which has a wonderful Vaccum section.

These guys know a lot thru personal experience in this and their previous life. They can be funny and some of us can't read or spell so pictures help. It is an adverse reaction from the brain scan before entrance in the witness protection program. They can really help you...just like the little lady down the street with the funny hat and a dozen rescued dogs and cats..they want to rescue every 107... with out wearing the hat.
See notations above
 
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