85 300SD: cranks, but won't start

Its a stock 5 cyl. 300SD. Has maybe 300K miles...hard to say as the odometer hasn't been working for a long while. It *was* starting up instantly when cranked, 5-10 seconds. Then a
couple of days ago, it began to take longer, a few seconds. Then when I drove to work yesterday, I had to crank three long times, then it started. Wasn't sluggish or rough at all when it did finally start, it was as peppy as usual. But when I tried to start it to get home, it would not start at all, no matter how much I cranked it. THe battery is up, there is plenty of cranking speed. But you can crank all day, and it will not start. It does not even try to fire even a litle bit. I thought it had lost prime, so I tried the pump trick more than once. No go, however. The weather is hot now. When it had bad glo-plugs in the winter, it would emit clouds of smoke as I cranked, from the unburned fuel I guess....now there is no smoke at all. If the timing chain has broken, wouldn't the loss of compression show as the starter turning at a much faster speed because of greatly decreased load? THis was how my Volvo 740 was when the timing jumped. It is still turning exactly the same speed with the same sound. I believe there is a vacuum line that has to be switched to enable the car to start, through the key switch. Don't know how to check this, though. I took the hard line to the no 1 injector loose and cranked the engine, and only a very small intmt. spurt of gas came out, even when floored. But shouldn't gas have come gushing out? I have a fuel press gauge somewhere, I guess I could buy some sort of tee and install in the flex line somewhere...but the gauge has a schrader valve, that is the problem. There is a fuel filter on the line right near the pump, but I can't see what is happening with the fuel as it is an opaque one. How should I proceed? For lack of funds I need to repair myself. ANy help greatly appreciated.
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Sounds like your fuel regulator is not allowing fuel during startup... you know that bellow thing that shuts engine off...
Do you have vacuum problem... like door lock etc?
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1. Open the lube oil fill cap and look (only) inside while the engine is cranked. If the cam turns the chain is OK.
2. On the left fender is the glow plug relay. It has a cover that probably pulls UP. Under that cover is an 80 amp fuse or link. Your car's is probably broken. Buy two, a replacement and a spare for "next time". Dealer sells these for about $1 or $2 each.
3. The engine smoked when SOME glow plugs were bad; it started because the others still glowed. Now nothing is glowing.
4. You did a good diagnosis in opening a high pressure line to check for fuel. That's how, but only a very small amount will leak as the motor uses very little fuel at idle. The fuel pressure in those steel lines is about 2,000 psi and will pierce your skin so respect it.
5. Change that opaque fuel filter; it ought to be clear enough to see the paper element.
Hope this gets you back on the road.
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Have you check to make sure the 50-amp glow plug fuse is okay? You can use a 12-volt test light to check the connection at each glow plug to see if you're getting current to them. You should have someone turning the ignition on and off to check at the glow plugs themselve. Otherwise just pop the cover off the relay and see if the link is still okay. You should use the 12-volt test light on those connections as well.Had this problem on my 300D, found a shorted glow plug, replaced it, along with about the 3rd or 4th fuse link, and finally things began working as designed. Good luck!
<geronimo> wrote in message > Its a stock 5 cyl. 300SD. Has maybe 300K miles...hard to say as the

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<geronimo> wrote in message > Its a stock 5 cyl. 300SD. Has maybe 300K miles...hard to say as the

When my 83 300SD was hard to start a while back, my mech suggested that I have the valves adjusted, which I did. It solved the problem for me. Of course, we made sure the glow plugs were operating right on, too. Hope this helps.
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