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Marty I put oil in all the cyilinders and redid the

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compression test, it ranged from...
Marty I put oil in all the cyilinders and redid the compression test, it ranged from 155lbs to 180. I put the plugs and wires on and kept the fuel pump relay out. loaded it up with starter flued and got it to turn over wrrrump for 2 seconds. I put back the fuel pump relay and it wouldn't start then backfired through the intake.
How should I proceed?
Submitted: 4 months ago.Category: Mercedes
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Answered in 53 minutes by:
12/1/2017
Mercedes Mechanic: Marty, Mercedes Technician replied 4 months ago
Marty
Marty, Mercedes Technician
Category: Mercedes
Satisfied Customers: 54,988
Experience: Bosch Certified Master Tech. Over 35 years experience.
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Hi Chris, I think we should first find out if the injectors are dumping fuel when you crank the motor. I have a feeling the plunger is stuck in the fuel distributor. You could remove all of the injectors from the motor and reconnect them to the lines outside of the motor then bypass the fuel pump relay with the key off and see if the injectors spray fuel with the relay bypassed (they shouldn't). You will need to bend the lines slightly in order to reconnect the injectors to the lines.

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Customer reply replied 4 months ago
Ok pull the injectors and control the output with hoses collecting the fuel. Then put a hot lead to the fuel pump with the engine off and fuel relay pulled. Your saying no fuel should come out of the injectors
Customer reply replied 4 months ago
Why pull all the injectors
Mercedes Mechanic: Marty, Mercedes Technician replied 4 months ago

I don't want them dumping fuel into the cylinders. You could pull the ones on the cylinders that had low compression and observe them rather than pull all 8.

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Mercedes Mechanic: Marty, Mercedes Technician replied 4 months ago

You don't need to control the output with hoses. You need to reconnect the injectors to the fuel lines after you remove them from the engine. You can power the fuel pump right from the relay plug if you insert a fused jumper lead from terminal 30 to 87.

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Mercedes Mechanic: Marty, Mercedes Technician replied 4 months ago

No fuel should spray from any of the injectors with the relay bypassed.

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Customer reply replied 4 months ago
Won't the injectors spray fuel all-over the engine if the distributor is dumping fuel
Mercedes Mechanic: Marty, Mercedes Technician replied 4 months ago

Yes, but you would then just pull your jumper if that was the case. Put some rags under each injector. You need to be able to see the tips of the injectors for the test.

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Customer reply replied 4 months ago
Okay
Mercedes Mechanic: Marty, Mercedes Technician replied 4 months ago

That's a good sign. Are you sure the firing order is correct?

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Customer reply replied 4 months ago
Absolutely checked 100 time's.
The green condenser wire from distributor to control box disinagrated where it connects to the coil. Twice I got a replacement from autohaus and they had no continuity and no ohm reading.
The old one has a ohm reading of 577 and have continuity to both contacts. I wrapped the worn section with a rubber hose and electrical tape. Since I am a one man show I connect the timing lite and I get strob from the#1cylinder. I haven't tested the other 7.
I replaced the distributor and control box and since I get the strob I figure they are fine. I also replaced the coil
Customer reply replied 4 months ago
Cap plugs and rotor as well
Customer reply replied 4 months ago
Should I put in the fuel pump relay and see if I get a atomized spray from the injectors that are out.
Do I have to crank the engine or Will they spray from the key in the on position
Customer reply replied 4 months ago
The green condenser wire disinagrated where it connects to the distributor not coil
Mercedes Mechanic: Marty, Mercedes Technician replied 4 months ago

You can install the relay and press down on the air flow sensor plate for a second or two to see if the injectors spray. They should start spraying as soon as you press down on the plate. Did it seem to fire on all 8 with the starting spray? If it did then I think the problem might just be the basic fuel mixture.

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Customer reply replied 4 months ago
Key switched on when I press the air flow sensor
Mercedes Mechanic: Marty, Mercedes Technician replied 4 months ago

No, just the pump running.

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Customer reply replied 4 months ago
Relay in key on injectors in bucket no spray. Key off no spray. I don't hear pump go on.
Customer reply replied 4 months ago
jump out the pump
Mercedes Mechanic: Marty, Mercedes Technician replied 4 months ago

You need to bypass the relay again like you did earlier.

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Customer reply replied 4 months ago
Ok doing it now
Mercedes Mechanic: Marty, Mercedes Technician replied 4 months ago

OK

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Customer reply replied 4 months ago
7 drips #5 stream #3 smaller steam #1 cloged looks like it needs new injectors
Customer reply replied 4 months ago
they whistle
Mercedes Mechanic: Marty, Mercedes Technician replied 4 months ago

They should whistle. Maybe pull them all and test them by pressing the plate down further. I don't want you to flood the other side of the motor.

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Customer reply replied 4 months ago
To late I'm sure I flooded the other side. I pushed it harder and got good spray patern. #7 and 3 keeps dripping
Mercedes Mechanic: Marty, Mercedes Technician replied 4 months ago

You should swap a good one with a bad one and make sure it's the injector and not the fuel distributor.

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Customer reply replied 4 months ago
7 still drips, isn't that controlled by the fuel distributor
Mercedes Mechanic: Marty, Mercedes Technician replied 4 months ago

Yes, they all should spray and turn off identically.

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Mercedes Mechanic: Marty, Mercedes Technician replied 4 months ago

It would be good to get 8 identical bottles and put the injectors in each one then do the spray test for 15 seconds and see what you get for fuel quantity. Also check the quality of the spray at different positions of the air flow plate. Purging them by pressing the plate way down may help to clean them.

I'll check back tomorrow.

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Customer reply replied 4 months ago
K
Mercedes Mechanic: Marty, Mercedes Technician replied 4 months ago

Good morning Chris. Let me know if you need anything.

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Customer reply replied 4 months ago
I will get to do the test eather late today or Monday
Mercedes Mechanic: Marty, Mercedes Technician replied 4 months ago

Ok Chris.

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Customer reply replied 4 months ago
Did the test cylinder#4 is constantly spraying hard out of control
Customer reply replied 4 months ago
Injector#7 is the only one that still drips
Injector#4 doesn't drip when pump is off
Mercedes Mechanic: Marty, Mercedes Technician replied 4 months ago

Try swapping the injector from cylinder 4 with a good cylinder and see if #4 line still sprays hard or it moves with the injector. From what you are describing I don't think this is the main issue. You could try turning the mixture screw 1/8 th turn counterclockwise to lean out the mixture a little. See if that makes #7 stop dripping.

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Customer reply replied 4 months ago
I will swap out the #4 injector but doesn't the fuel distributor control what ever injector is on cylinder#4. I would think even a new injector would act the same
Customer reply replied 4 months ago
I swapped#2 and#4 injectors. #4 still putting out without pushing the air flow down. The injector that was on 4 now 2 spraying iraticley stream and spray depending on position of air intake
Customer reply replied 4 months ago
2 and#7 are dripping
Mercedes Mechanic: Marty, Mercedes Technician replied 4 months ago

The fuel distributor allows fuel to flow evenly to the injectors. Each injector should act the same. If #4 sprays without pushing the plate down we have a problem with the fuel distributor. Try turning the mixture back 1/8th turn at a time and see if you can get #4 to stop spraying. Let me know how far you have to turn the mixture to make it stop.

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Customer reply replied 4 months ago
I turned it counter clock wise 3 revolution until I couldn't turn it anymore and fuel still spraying
Mercedes Mechanic: Marty, Mercedes Technician replied 4 months ago

Chris, that sounds like you have a bad fuel distributor. Can you send me a youtube video of what it's doing?

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Customer reply replied 4 months ago
YouTube LOL I'm lucky I can handle texting. I can take pictures and video but the phone won't do audio. I will contact Verizon later. This fuel distributor was replaced 1996 . I will remove it and look at the plunger otherwise I will get a rebuilt. I read to rebuild it myself is difficult because it needs calibration. If I take it apart it won't be returnable as a core
Customer reply replied 4 months ago
Fuel distributor out and plunger movement is perfect, should I try to screw with it or just get a new rebuilt
Mercedes Mechanic: Marty, Mercedes Technician replied 4 months ago

Since you had 1 cylinder spraying fuel I would replace it or send it away for a rebuild. I recently had success using Fuel injection Corporation in California.

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