om617 IP suddenly died, 1981 non turbo 300td
 

Hey guys,
Not sure how this could happen as I understand it to be rare as hens teeth. It seems as though my friends injection pump just decided to kick the bucket. This was fully functioning and sitting there idling and POOF! It just stopped. I cant get anything to come out of the pump. The vacuum shut off is functioning properly, all the linkage seems to be doing its job. New manual pump has completely flooded the Injector pump and is flowing in and out easily. Very strange. Ideas? This is an 81 non turbo 300td

Thanks, Opossum

Hmm
 

Remove the injection pump timing plug.

Use a mirror and bright light to look in while the engine cranks = verify the cam is rotating.

If it is not = it may be a timing device or coupler failure, or one of these issues.

http://www.peachparts.com/shopforum/diesel-discussion/239595-diesel-injection-pump-timing-device-threads.html

http://www.peachparts.com/shopforum/diesel-discussion/269800-ip-throttle-rack-jammed.html

http://www.peachparts.com/shopforum/diesel-discussion/239597-alda-issue-threads.html

http://www.peachparts.com/shopforum/diesel-discussion/296400-fyi-inline-diesel-injection-pumps.html

http://www.peachparts.com/shopforum/diy-links-parts-category/142405-diesel-injection.html

Have a great day.
.

There is also the Fuel Pressure Relief/Overflow Valve. If that stopped holding pressure your Fuel Injection Pump will not get enough pressure to feed the Elements.

Replace the large Fuel Return Hosel (Cigar Hose) with a section of regular 5/16" Fuel Hose that is long eoungh for you to run into a Bottle (a cleal 1 liter Soda Bottle would be OK) to catch the Return Fuel. Start pumping on the Hand Primer till you get a good stream of Fuel coming out. When the Fuel is coming out good have someone clamp off the Hose with a Vice Grips or something else.

clamping off the Return Line means the pressure from the Fuel Supply/Lift Pump cannot be relieved and your Fuel Injection Pump is going to get pressure.
See if the Engine will Start like that. Only run it long enough to verify it will start. If you run it too long like that I would expect one or more of the little Fuel Return Hoses to come off or pop.
Anyway if it starts like that I would think that means the Fuel Pressure Relief Valve is shot or needs to have the Spring stretched to a 27mm Free Length.

Do you get Fuel out of the Fuel Supply/Lift Pump when you crank the Engine? If not there is likely something wrong inside of the Fuel Supply/Lift Pump. Note that while the Hand Primer attaches to the Fuel Supply/Lift Pump except for the Valves in the pump it operates independently.
That means if the Piston inside of the Fuel Supply/Lift Pump got stuck or the Piston Spring broke the Hand Primer is still going to work fine.
Have you tried Pumping the Hand Primer while you are trying to start the Engine?

If the Crankcase Breather tubing is blocked off it will cause the Engine to shut off. When I blocked mine off with My thumb it took only 7 seconds till the Engine started to shut down.

If this was an Engine that sat a long time and you just started it is possible for gummy Fuel or Rust inside of the Fuel Injection Pump to cause the Element Plungers to stick upwards. The same applies to the Fuel Supply/Lift Pump piston

Thanks for the ideas guys. Exactly what I needed. I didnt have anyone helping me so I couldnt see if the cam is rotating. I suspect it is and the plungers are stuck upwards. This car had been sitting for several years. I read another post where the guy used transmission fluid to soak and free up his stuck plungers. Will report back soon. Thanks again!