81 300D won't start

My son came home in his 81 300D & turned the engine off. It now won't start. I checked the fuel lines.. they seem to be pushing diesel through. It sounds like it is compressing, but no firing. It is in
the 60's here.. not real cold so even if the glow plugs were all out at once it should still sputter, shouldn't it?
I've searched the archives at mbz.org, & struggled through the mb manual on a disk but to no avail.. i am not sure where to begin. It seems unlikely a timing chain would have slipped or jumped.. fuel seems to be flowing through the injectors.. I even removed the air filter & tried to spray some diesel directly into the intake manifold. ..still no fire. Any ideas out there? Thanks, everyone for the replies (in advance!).
Scott Wilcox Sedona, Arizona, USA
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On the left fender is a black box - the glow plug relay. There's a plastic cover that slides UP to expose its 80 amp fuse. This is probably broken resulting in no glow plug action. IMHO a very experienced engine like this one needs the glow plugs to start.
One can temporarily jump the fuse with some stout copper wire, a replacement fusible link is available from dealer and on-line parts houses for about $1. Also buy an spare one.
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Tom, you really are The Man.
We worked on the car all afternoon, then i posted this message. You answered in less than 15 minutes, we went out & checked the link.. sure enough, it was fried. I put a piece of copper wire as a temp & it fired right up. Paul was ecstatic! I won't have to drive him to school tomorrow, & he's back in wheels (plus he didn't have to have it towed to the shop!). We owe you, man.
If you come to Arizona, send me an email & let me know when. I'll be glad to take you to lunch and out for a round of golf. Sedona is a nice resort area, & Paul could give you the grand tour.
Thanks again for your help. You are amazing. You answer so many messages on this group, freely giving helpful advice.
Scott Wilcox Sedona, Arizona, USA

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A happy coincidence.
These old diesels are pretty simple machines so, when something's wrong, think of the simple stuff first and that's usually THE problem's cause.
A beer at The Noname bar in Sausalito would be great!
Tom
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