Please read! Need help fast! Easy fix I hope!

[brockley]

I was driving my 84 500sel into my driveway and the engine cut off for no reason. Now when I try to start the car, the starter is working but the engine wont turn over or it will briefly then the starter will just be running till I turn the key off. I opened up the hood and noticed a loose hose. This is the hose that is attached just below the cap to the engine coolant reservoir. There is a hose that goes out to the radiator and on the opposite side just below the cap (points toward battery) there is a hose that is not connected to anything. does anyone have an idea where this hose goes? If you could just open the hood of your w126 (if you have one or any other 1980s mb should be the same) and see where the hose on the battery side of the coolant tank is connected to. thanks in advance for your help.
Brett

[Jim Anderson]

If the hose comes out from under the pressure cap but above the rubber seal in the cap thats just a vent that dumps to the outside world when the radiator cap releases pressure.

Your starter sounds like a bad starter gear bendix ratchet widget. Its supposed to turn one way but not both in case the engine startes and the starter is still engaged, yours is turning both ways. Time for R&R. A trick I can't explain is to let go of the starter before it disengages. For some reason the engine will start when you do that, even though its cranking less.

[brockley]

Thanks for the quick reply but I think I typed the wrong info. The engine does turn over, but it does not catch. When I turn the key the starter kicks on like its supposed to and the engine turns over like it should but it almost acts like there is no gas getting to the engine so there is nothing to combust and therefore it wont start. does anyone have a solution to this before I have to have it towed to a mechanic? thanks again.

Hey califlower Imean brockley Sorry but I just can't help myself.Ok lets see if I got this straight.You pulled into your driveway and the car quit runnig by itself? Then when you go to start it the starter turns over but does not make contact with the ring gear on the motor /transmission?If this is all that is happening at one time Yikes!! as far as the starter it sounds like your solenoid is bad on the starter I would get a whole rebuilt starter or find a place in your area that will rebuild the starter for you .or I guess you can get a solenoid for the starter. and as far as the motor dieing in your drive way we will need more info to help figure out what broke ,like do you have any spark?or is the fuelpump kicking on when you turn the key to the on position?let us know so we can help you.

[MikeTangas]

Turn the key on, but don't try starting the motor. Do you hear the fuel pump pressurizing? If not check the fuses, and replace the fuel pump fuse even if it looks good. Next, try the above test again and see if the pump spools up.

And how about zzzzfuel pump relay?

[brockley]

I turned my stereo off, rolled down the windows (while the key was in accessories) waited for the antenna to fully extend, then turned the key to the on position. I did not hear anything except for the beep telling me my seatbelt wasn't fastened. I did notice that a orange triangle to the left of the R on the fuel gauge lights up when the key is in the on position. I hope that means something to someone out there and that it will help me get to the bottom of this problem.
Thanks again.
Brett

[Rich126]

The orange light near the fuel gauge is always on until the car starts.

[brockley]

I guess i never noticed it before. where sould i be listening for the fuel pump? back near the gas door or somewhere else?

[Rich126]

Yes, in the rear behind the gas door - it should hisssssss, some people guess that the sound is exhaust. Have someone put the key in while you put your ear down behind the rear passenger side tire, when the key goes to the ON position, it should cycle once and "hiss" about 3-4 seconds. If this does not happen, you're fuel pump is not working - check the fuses. If they're blown, it's probably a temporary fix as the pump is probably getting old and shorting them out. I had this on 2 of the 4 W126 cars I own(ed )- usually with between 150k and 175k miles.

I read what you wrote before, and your starter sounds "normal" right? Just the car is not starting like it would not be getting fuel?

[Rich126]

Hold on I'm mistaken.. check your fuses anyway but that's probably NOT the problem.

I'm 25 and i think my mind is going.. THIS is the problem I had twice:

I THINK IT'S THE RELAY. When the fuel pumps get old, they short out the FUEL PUMP RELAY. This relay exists to cut fuel in the event of an accident, I believe, so fuel doesn't dump out all over after your crash or something to that effect..

Open up the hood, behind the firewall, next to the fuse box (left of it looking to the rear of the car), there are two relays next to each other, both are rectangles about 3" x 2" x 4" (WxLxH) give or take a little on the dimensions. One is idle control, one is the fuel cutoff - you can tell the difference because the fuel pump one says something about 8 zyl. 6500RPM blah blah on it - pull it out. Look at the pins on the bottom of it, tell me what the numbers are -

When you list them, I'll remember which 2 pin locations to jump (with a paperclip) - and the car should start.

[MikeTangas]

Unless that orange/yellow triangle had been on for some time before the car died. That triangle should be your low fuel indicator, and once it comes on you should locate a gas station post haste.

[brockley]

Problem is fixed thanks to rich126. here are the instructions from Rich:

Go to where your relays are and pull out the biggest one (the case in my 84 500sel). It should be a black plastic covered relay and not one of the small metal cased ones. it should have seven pins.

pull it out and look at the number labels on each of the pins.

Find the one labeled 15 and the one labeled 87. Look into the socket that the relay plugs into an see which sockets the 87 and 15 pins plug into.

Take a paper clip and unfold so the two ends meet and it is kind of like a clamp.

Put each one end in each socket and try to start your car. it should start right up.

According to Rich, you should be able to drive around town like this for a few weeks until you fix the problem as stated above (replace fuel pump). Do not just replace the relay because the bad pump will break your new relay and you'll have to buy a new one.

Hope this helps more people since it seems to be a pretty common problem with the w126 cars.

[Bzoo]

did your timing chain break

Way to go Rich 126 you da man cheering from the crowd .