How to determine bad Injector Pump?

[DieselNoob]

Hello, I saved a 1983 300D from the junkyard. It has received flood damage and the compressor and alternator were locked up so I cut the belts and now the engine spins over via use of the starter.



I've ran new hoses to a gatorade bottle of diesel, and I've primed the pump with the manual pump by pumping it 100 times or so.



I've disconnected the vaccum lines and have inspected the linkage externally to make sure the injector pump wasn't being turned off by the fuel shut off mechanism.



I've loosened the banjo fittings and fuel is getting to the injection pump.



I've pulled a hard line and all I am seeing is a drip when the injector pump sends fuel to the cylinder.



Is just a drip normal?? I've never seen one in person and have never worked on diesels for that matter.



People have told me to just connect the line and crank and crank it over, but I've done that to no avail.



How can I determine that the injection pump is good or if the lines just need more bleeding/pumping to build pressure.


Thank you.

[brownrice78]

the primer pump might not be working altogether...loosen the lines going to the engine (on top of the injectors)....crank the car over and over and you will start to see fuel coming out of those lines....then tighten them and crank again with your foot on the throttle, the car should start running. Unless the injection pump is completely dumped, the car should run....maybe not good...but it will run

[hercules]

Did you feel some resistance on the primer pump and hear the fuel regulator buzzing?

The injection pump has a start mode,push throttle to floor (engine key on to glow)
let off throttle,crank,20 sec. let starter cool for a min.
Start mode gives extra fuel,opening
throttle pushes rack out of start mode.When engine begins to fire can very lightly open
throttle. Starter rpm not enough to move rack for more fuel.

[barry12345]

Are the glo plugs working? Spray some wd40 down the intake with the air filter cover off to make sure it can run. Chances are very strong that if the car was in some kind of flood damage. It had been running just prior to the incident. So the injection pump itself is probably just fine.

[DieselNoob]

It lives!!!

I have to admit that I foolishly was trying to start it with an undersized battery. A jump from a big truck made the old engine fire up very quick. It seems to run great!

So, I've learned about the battery, and I've learned that with slow cranking not much happens at the end of the hard lines, just a drip when the injector pump squirts fuel to the cylinder.

Thank you all for the advice!

[Maxbumpo]

Originally Posted by DieselNoob

I've learned that with slow cranking not much happens at the end of the hard lines, just a drip when the injector pump squirts fuel to the cylinder.

It is not a very large volume of fuel for sure, others have been in doubt as well.

[Diesel911]

Since within the last month this happened to a member you need to remove part of the intake so that if the Engine takes off high revving/running away by itself you can quickly stop it by blocking off the air to it.