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I JUST BOUGHT AND 83' MB 300SD TURBO DIESEL AS IS. I TRIED STARTING IT, AND IT DIDN'T FIRE ONE TIME. THE MOTOR TURNS OVER FINE, SEEMS A LITTLE SLOW BUT PROBABLY BECAUSE OF THE COMPRESSION. SPRAYED SOME ETHER INTO THE TURBO INTAKE AND GOT IT TO POP A FEW TIMES. SO I FIGURED SOMETHING MUST BE WRONG WITH THE INJECTION. I PULLED THE LINES OFF OF THE INJECTORS AND THE FUEL ONLY DRIPS OUT WHEN I TURN THE MOTOR OVER. SHOULD IT HAVE MORE FORCE BEHIND IT? I THOUGHT INJECTION PUMPS WERE SUPPOSED TO HAVE HIGH PRESSURE? THERE WAS PLENTY OF FUEL SHOOTING OUT OF THE LINE LEADING TO THE INJECTION PUMP WHEN I DISCONNECTED IT. MY GLOW PLUGS ALL HAVE ABOUT 12 VOLTS RUNNING TOO THEM. SO IT HAS TO BE A FUEL PROBLEM. IS IT THE INJECTION PUMP?
 

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Please, no caps with bold. All caps is the same as yelling.

This thread may help: http://www.benzforum.com/forum/viewtopic.php?t=3733

But, also let's idendify which lines you pulled. Were they the metal or the rubber lines? The rubber lines should not have a whole lot of flow since they are the return lines to the tank. This means the excess fuel from the injector goes through there.

If you are talking the metal lines, then yes, they should have good pressure. It would be surprising to me since injection pumps rarely go bad. Is the camshaft turning when the engine is cranking? It should be visible thru the oil cap. If not, there is likely a timing chain issue. If so, and the metal lines are not putting out pressure, you may actually have a bad injection pump. I would first try putting something like pure "diesel doctor" or "diesel purge" through it.

It is advisable to not use ether to start the engine. This is for two reasons. First, the fuel systems count on the oil characteristics of diesel for lubrication. Second, using too much can damage your rings.

For the glow plugs testing, check this link: http://www.benzforum.com/forum/viewtopic.php?t=4265&highlight=glow+plugs
 

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I know that ether is not designed or recommended for diesel but diesel starting fluid would not make it all the way through the turbo and intake. The metal lines that supply the fuel to the injectors have such low pressure that the fuel just drips out on every crank of the injection pump. The pump is being supplied with power and fuel and the timing chain is fine. My glow plugs do have power to them but the light does not turn on. So do I have two problems the injection pump and glow plug relay? I haven't checked the relay fuse yet but I will tonight. Also I have heard that there is some kind of adjustment on the injection pump for fuel pressure. Where is that located, if it exists?
 

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Sounds like you have a better idea of how the glow plug system works. Don;t forget that the light bulb could be burnt out on such an old car as well. How many miles on this thing, BTW?

First thing first, make sure that the lever at the side is UP when you are trying to start the engine. Sometimes it will get stuck down, thus killing the engine as it would for a normal shutoff. Also the vacuum lines will sometimes get switched around incorrectly, causing the lever to go down to the stop position when it should be up for running. You may need somebody to crank the engine while you watch this.

Good point on the fuel adjustment on the injection pump. I ignored that possibility because it is usually a factory set and forget item. However, many people do gain some power by playing with this (myself included) and who knows what maniac was messing with your car before? Anyway, the device you are looking for is called the "ALDA" and a search of this forum should be helpful. Basically it is the flat (at least I think your OM617 engine has a flat one - mine are more like doorknobs) device atop the injection pump with a vacuum (actually pressure) line going to it from the manifold. There is a screw (with a locknut) on top of this that can be turned counter clockwise to enrichen the fuel mix. This may help, but is usually a last resort item.

Hope this helps.
 

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Still hardly any fuel. I don't know if I should blow money on an injection pump or not? They are like 100 used. How hard is this to install? I don't know what to do. I just want to drive my benz.
 

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In reading your first post, you mentioned pulling the fuel line to the IP off. Did you prime the IP afterwards? It might be as simple as opening the bleed screw, unscrewing the knob on the side of the IP, and pumping it until you have good fuel flow and tightening it all up again. Then you can try starting the engine.

I have to say that $100 for an IP is a really good price, but changing the IP is a bit of a PTIA that needs a couple of special tools (not prohibitively costly). If you do choose to replace the pump, then it may be advisable to replace the timing chain as well. I would hate to give up on the existing pump, though.
 

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GETTING IMPATIENT

where is the bleed screw located? could it be gelled up inside the intake of the injection pump? If so what kind of cleaner should I run through it? I am getting very impatient with this car. I am ready to give up or buy an injection pump. I just want it to make some progress.
 

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The bleed srcew is at the top of the IP. I just sent you a PM that should show it.
 

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I JUST BOUGHT AND 83' MB 300SD TURBO DIESEL AS IS. .. THE MOTOR TURNS OVER FINE, SEEMS A LITTLE SLOW BUT ..
Weak battery. Motor must spin FAST to build compression heat. Remember, it's the hi-voltage arc that lights up a conventional, gasoline engine. By comparison, diesel is much less volatile; nowhere close in refinement when compared to gasoline.
 

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I JUST BOUGHT AND 83' MB 300SD TURBO DIESEL AS IS. I TRIED STARTING IT, AND IT DIDN'T FIRE ONE TIME. THE MOTOR TURNS OVER FINE, SEEMS A LITTLE SLOW BUT PROBABLY BECAUSE OF THE COMPRESSION. SPRAYED SOME ETHER INTO THE TURBO INTAKE AND GOT IT TO POP A FEW TIMES. SO I FIGURED SOMETHING MUST BE WRONG WITH THE INJECTION. I PULLED THE LINES OFF OF THE INJECTORS AND THE FUEL ONLY DRIPS OUT WHEN I TURN THE MOTOR OVER. SHOULD IT HAVE MORE FORCE BEHIND IT? I THOUGHT INJECTION PUMPS WERE SUPPOSED TO HAVE HIGH PRESSURE? THERE WAS PLENTY OF FUEL SHOOTING OUT OF THE LINE LEADING TO THE INJECTION PUMP WHEN I DISCONNECTED IT. MY GLOW PLUGS ALL HAVE ABOUT 12 VOLTS RUNNING TOO THEM. SO IT HAS TO BE A FUEL PROBLEM. IS IT THE INJECTION PUMP?
I did not read all of the other posts so some of this could be a repeat.
If you use Starter Fluid you need to pull the rectangular connector out of the Glow Plug Relay. That disconnects the Glow Plug so they won't ignite the Starter Fluid too soon.

Next you need remove the air intake where it goes into the Turbo Charter.

The most important step is to have someone else start cranking the Engine before you start spraying in the minimum needed to start. That avoids spraying in a lot of Starting Fluid and you running around to crank and having a large slug if Starting Fluid suddenly hitting the Engine.

Concerning the high pressure from the Injection pump the Injectors control the pressure. The Injectors are sort of like spring loade pressure relive valves. Also never put you hands or fingers or any other body parts over the ends of the steel fuel injection hard lines as it will inject Diesel Fuel into you and it really Fs up tissue.

The next time before you attempt to start pump about 50 times on the hand primer until you hear a quiet buzzing or sound coming from the Fuel Injection pump. That give you at least some idea if the fuel supply system is primed.

If the Hand Primer leaks replace it as it will just case air to get into the system and when air get up into the steel fuel injection hard lines it compresses and does not want to move out and you can easily kill a better trying to get it out.

To get the air out you loosen the fuel injection hard line nuts at the Injectors and crank till you are sure you are getting fuel out of all of them. That leaves a way for the air to get out.

If you see any black or greenish solid matter inside of the plastic fuel filter it could be you have stuff growing inside of the fuel tank.
 
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