I went out to start my car this morning. No go. Engine fired but wouldn't stay started. The car started and ran fine a couple days earlier, with no noticeable lack of power or anything like that. I did finally manage to get it started hours later but not without a lot of cranking. I loosened the injector line nuts and fuel came out from all four, so I don't think it was a fuel delivery issue. Both fuel filters and the strainer were replaced/cleaned a couple weeks ago when I had the tank off to patch a leak. No bubbles in the line from the pump to the secondary filter or in the primary filter either, nor are there any wet spots under the car (at least not diesel ones ). Glow plugs work (when one goes out on this car they all stop working completely, as does the salt shaker-looking thing). Valves were adjusted a couple thousand miles ago. Tank vent is clear. Only possible thing I can figure is moisture getting in the intake from sitting in my fairly humid garage, but I took the air cleaner off and found no moisture in the part that runs from the air cleaner to the manifold, or in the manifold itself.
At my wit's end here, any suggestions?

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1973 220D ~135k Mi
1979 Ford F100 300 I6 - 225k Mi

Restarting the car a few hours a later I find that it starts on the first crank, runs fine for a few seconds, then sputters out and dies. A few hours ago it was idling and revving just fine.

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1973 220D ~135k Mi
1979 Ford F100 300 I6 - 225k Mi

Is this new dying out on the same fuel as when it ran ok OR did the problem start after a refuel.

There is a rubber mount 3 point IIRC on the start stop cable. Check its condition, I think if they fail the fuel could be getting shut down to the pump.

Check the air intake for restrictions.

Is there fuel in the small inline primary filter? How does the fuel look?

Good luck!!!

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"Rudeness is a weak man's imitation of strength" - Eric Hoffer

Fuel is the same as it was when it was running fine and looks fine. Primary filter has fuel also. Tried starting with the air cleaner removed but that didn't help either

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1973 220D ~135k Mi
1979 Ford F100 300 I6 - 225k Mi

Follow the fuel shut off cable under the hood to the injection pump looking for broken mounts, brackets or a slipped/moved adjustment.

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"Rudeness is a weak man's imitation of strength" - Eric Hoffer

Check lift pump output. Or if you have a primer pump. Have someone pump it while you start the car. Plus keep pumping it after the car starts. Of course if it continues to run well the lift pump will require further testing.


I suppose the relief valve may be stuck open is also another possibility. But as the primer pump is used a stiffness should develop if that relief valve is normal.

Also remember that in a series string of glow plugs they will still appear to be working if one towards the front of the engine shorts internally to ground. Since your car actually starts and dies out. This should not be the problem.


Anyone play with the idle control knob on the dash? Our 77 300d would not get going after the daughter turned it down years ago. That is if your year has one.

When hand primed resistance is felt on the first push as the fuel system appears to pressurizing fine. Start/stop cable is fine also. Idle speed is at max. This morning I noticed visible condensation in the engine bay so I pushed the car out of my garage and into the sun in hopes it would dry out. After much cranking I was able to get it started again, albeit with much injector nailing and white smoke that smelt of diesel fuel. I let it idle for the better part of an hour and this seemed to dissipate and the smoke cleared up, or at least returned to its normal level. Are these symptoms consistent with having water in the intake? There's not much else I can think of.

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1973 220D ~135k Mi
1979 Ford F100 300 I6 - 225k Mi

You could try pop testing the injectors.

Dkr.

If you own a voltmeter. You should see about 1.3 volts between the hot wire feeding the first glow plug. At the front of the engine and ground. With the glow plug circuit energized.

If a loop plug shorts internally the shaker will still light and even some glow plugs may operate. I doubt this is the problem. On the other hand I have had some diesels that just did not want to start and run with a glow plug or two not working.

This condition you describe as condensation under the hood seems strange to me. I live in eastern Canada and resided in the Toronto area of Canada in the past. It may be common but at the same time I never remember catching that condition with a car.

Taking an hour to settle down after starting is another strange thing to me. Any evidence of say a head gasket leaking under the hood? I also wonder about water in the fuel.

If that is really condensation under the hood. It will possibly be condensating heavily in the fuel tank. I might pull the fuel filter and dump the fuel in a glass jar looking for water after the contents settle a little. Actually this is the first thing I would do now as even if there were a problem with the glow plugs. The engine would not take that long to recover once started.

Technically you may have blown the head gasket as well. Look in the radiator when running for bubbling etc. Do this before the engine coolant gets too hot. Do no scald yourself. A bad head gasket can make the coolant gush out when the cap is removed sometimes. Better to start the engine with the rad cap off.

Last night I cleaned the few rust particles out of the prefilter (not enough to actually impact the flow of fuel, most of it was stuck to the magnet I have attached to it) and changed the oil in the air filter to make sure no water was stuck in there or anything. This morning I tried to start the car and it started on the first crank. Didn't stall or hesitate either. Very odd.

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1973 220D ~135k Mi
1979 Ford F100 300 I6 - 225k Mi

With some further troubleshooting I've found:
The car seemed to stumble a bit when I drove it around my yard
When left parked with the front at a higher angle it seems to have some air incursion
The only place with any diesel seepage is the big nut on the lift pump, all rubber lines from the tank to that point are new (less than a year old) with no signs of any leakage and all clamps are tight.

I replaced the valves and the primer pump on the lift pump about a year ago when I had a similar problem. I accidentally tore one of the O-rings in the rebuild kit and replaced it with a generic one and sealed around the outside of the banjo bolt with RTV silicone. I do see a few very small bubbles when I hand prime but none when the pump is being driven by the engine, except when parked uphill as mentioned above, but then I only see a couple bubbles and those quickly dissipate, leaving me to believe the air is getting in through the lift pump where the fuel is seeping out when it's not under pressure. Could the lift pump be the problem? How does one check its output? I also checked for signs of a blown head gasket but found nothing. I don't think it's a valve out of adjustment or an injector bad because of the problem's inconsistency. Glow plugs seem fine as it starts on the first crank consistently now.

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1973 220D ~135k Mi
1979 Ford F100 300 I6 - 225k Mi

Any other possible explanation before I go ahead and order a new fuel pump?

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1973 220D ~135k Mi
1979 Ford F100 300 I6 - 225k Mi