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81 300SD Engine Choking

I had a strange incident last night driving my 81 300 SD Turbo Diesel. While running at about 40 mph downhill on a bridge, the car started to slow down. I floored the accelerator pedal and the car didn't respond. I pulled over and the engine began to run rough, as if it is choking and ready to cutout by itself, but it did not. I turned off the ignition and waited about 30 seconds and started the engine again. It started immediately but idled rough for about 20 seconds and after stepping on the accelrator while on idle a few times, the engine started to run normal. I was able to drive the car home for about 8 miles as if nothing happened. This morning, the car started normal and was able to drive it again, but after about 5 miles, the same thing happened. The engine was not responding even though I floored the accelerator pedal. I again pulled over while the engine was running rough and turned off the ignition. After 30 seconds, I started the engine and it idled rough for about 20 seconds and after stepping on the accelerator a few times, the car seems to be normal. Is this fuel related, i.e., clogged fuel filters or something serious that I need to take to a mechanic? Are there any additives I can add to the fuel tank such as "dry gas" as I thought maybe there is moisture in the fuel tank/lines. I noticed the in-line fuel filter to be dark brown in color instead of almost clear platic when new. Does this indicate that the fuel system is dirty and clogged. I live is South Jersey and I don't think the temperature has dropped that much yet to affect the fuel system. Sorry for the long post and thanks in advance for any help.

Reply to
Newbie
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I have had a similar problem before, may be something to check, but maybe there is a vacuum in your tank? I would open the tank to fill with fuel and hear a whoosh as the air was going back in. Just a thought!

Reply to
TimmyD

Always check the simple things before getting into the complicated stuff.

Fuel filters are the first thing to check. The spin on can above the injection pump and the small see-thru plastic filter down at the hand primer pump. When you replace these you need to expel the air from the fuel system by using the (round, black capped handle) hand primer pump; unscrew the handle and pump until there are no air bubbles in the clear plastic fuel lines on the engine. Other possibilities. There's also a pick-up screen inside the fuel tank that could be clogged. There's a vent on the fuel tank that should be open. There are some short hoses to and from the fuel tank that could be defective or kinked. None of these repairs needs a mechanic but the fuel stinks so wear plastic gloves.

Algae grows in water and diesel fuel sometimes has a bit of water in it. Algae is NOT killed by diesel fuel and so will grow in the fuel system. Gasoline kills algae so, if you find evidence of algae, a gallon of regular in the fuel should do the job. Killing it will put it into the filters so be prepared for a couple of iterations of changing fuel filters.

These old 617 engines can run on lower octane gasoline but will not start as easily and lack full power. Newer CDI diesels' fuel systems will be damaged by gasoline so CDI owners should never introduce gasoline to their fuel systems.

Reply to
T.G. Lambach

Thanks for the advice. I forgot to mention a few things that I thought I should have included in my earlier post. I always fill the tank whenever the gage is half full except this past week where I have to drive some long distances and was driving the car with the fuel gage close to just 1/4 full. I also noticed this morning when I opened the fuel fill cap, the cap had some moisture. I assume it is moisture as it does not mix with what i think is diesel spill in the fill cap. I will definitely check the fuel filters. Thanks again.

Reply to
Newbie

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