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Discussion Starter · #1 ·
Hi y'all, im a new member here and already right off the bat have a question. I have seen threads asking similar questions but none have helped me so I am going to post my own. I have a 1986 f250 6.9l 4spd manual, picked this truck up running and driving made it 350 miles no problem for only $600. With $80 worth of copper in the bed, new sound system and new tires, RUNNING i figured it was to good of a deal. Well a couple thousand miles later I am hitting my first problem. Drove to Nevada,TX to san antonio a couple times this week. After the first trip i had a very rough idle for only the day after than ran fine for 3 days. On the way back on the second trip after running about 200 miles I stopped for a drink, started with a very rough idle, ran on as I got up to speed, slowed down and it started sputtering very hard. Thought I may be low on gas ( gauge doesn't work) switching to my reserve didn't fix the problem however, as soon as I hit the shoulder it died out. Was cranking fine but no start then got to the point it would barely crank at all. This is the only information I have, the injection lines all have gas line wrapped around them almost as if there is a hole could I be getting air in the lines there? Lift pump?
 

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Welcome to the forum, Sounds like aeration to me.
Those 6.9 injector lines cracking is the thing I remember most about that engine. Those trucks melted away years ago up here if not maintained. It has been over a decade since I worked on one. I would go thru the fuel system from back to injectors looking for restrictions and possible aeration points.
 

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Welcome to the TDS

What is gas line wrap?

The injector hard lines has to have the clamps on them or they will crack/break at the connector nuts. That's due to diesel vibration. See pic.
If the clamps are not on, they are obsolete, junk yard is the only source.

At a 1/4 of a tank of fuel, you will run out of fuel if the pickup screen is not on the fuel sender. Your symptons of sputtering tells me that they are not. See Pic.
You have to drop the tank or pull the bed to access the sender.
Another cause is,the lift pump could also have given up.

Prolong cranking will certainly run the batteries down, diesels are hard to turn over due to the hi compression, thats why there is two batteries.
 

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Discussion Starter · #4 ·
I'm praying is isn't the injector lines I can't find them anywhere for less than 80 a piece. any way to test if the hard lines are cracked? I can work on vehicles but this is the first diesel I have ever got into/
 

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Discussion Starter · #5 ·
Welcome to the TDS

What is gas line wrap?

The injector hard lines has to have the clamps on them or they will crack/break at the connector nuts. That's due to diesel vibration. See pic.
If the clamps are not on, they are obsolete, junk yard is the only source.

At a 1/4 of a tank of fuel, you will run out of fuel if the pickup screen is not on the fuel sender. Your symptons of sputtering tells me that they are not. See Pic.
You have to drop the tank or pull the bed to access the sender.
Another cause is,the lift pump could also have given up.

Prolong cranking will certainly run the batteries down, diesels are hard to turn over due to the hi compression, thats why there is two batteries.
I apologize I wasn't very clear when I said "gas line wrap" The injector hard lines are all there (with all the necessary clamps) but each of them has small sections of simple black gas line put around them held on with zip ties. Just normal fuel line that you can buy at auto zone by the foot. Is there any way to test if it is the lift pump? I last thing I want to do is drop my tanks. Is it common for both of the pickup screens to fall off at the same time I seem to get no feed from either tank. Did this sputter one other time only for a few minutes the week before than nothing until this long trip. Injection pump?
 

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Fill both tanks, then run it on one tank til it's down to a 1/4 tank, if it's sputters then, then you'll know the shower head has disingrated or fallen off.
 
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