Purging air from fuel system

keithwld

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I am going to pull my bed and change both sending units on my 87 f250 6.9 tanks. I want to change the rubber fuel lines and move my water separator down to the frame rail in front of the side tank. My question is how do I go about bleeding my system after all this work? Thanks in advance Keith
 

79jasper

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Disable ip, then crank until you get fuel to the engine. Give starter breaks of course.

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Agnem

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No real reason to disable the IP. I'd rather disable the glow plugs. Just have the schrader valve depressed and crank until you have fuel.
 

IDIoit

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I just swapped my dual tanks to a single 32 gallon tank.
Deleted separator, I did not mess with the fuel system from the lift pump on up.
When I put it all back together, I just fired it up like normal,
She did run like crap for a few seconds but immediately cleared up with a few revs to half throttle.
Drove her down the road without a glitch. And starts up on the first try the next morning.

Am I doing this incorrectly? In the course of my 6.9 and 7.3, I have never disabled my IP or GP's
I haven't had a problem, what am I damaging ?
 

icanfixall

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Welcome to the forum. Cranking till fuel comes out the schrader valve on the filter head is ok but make sure you don't crank longer than about 15 or 20 seconds. Cranking longer can ruin the starter because it gets very hot from cranking. A low battery charge makes it even hotter quicker. Allow the starter to rest for 2 minutes to cool down. Not doing this will smoke the starter. That means you find that magic point of how to get all the smoke out of the starter windings..:angel: Once you see smoke raising from that area of the engine its long too late to save anything. Its new starter time and thats going to cost $85.00 thru DB electricl on ebay at the cheapest. Many other starter supplies are much more expensive than that too. Why are you wanting to move the filter? Its fine where it is and you can change the filter without crawling under the truck. Remember that gravity will drain the fuel down your arms and end up in the arm pits... It burns in that sensitive area let me tell you. You'll only do that once.
 

keithwld

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My separator was changed to a filter by the po and then another one unhooked it so it has been deleted. I am going to hook it back up and may put it next to the fuel filter but it is really hard to get at the filter where it is on the drivers side firewall. The original location was probably good when all you did was lift up the drain ring once in awhile but if I put a drain style filter back on it will be hard to drain the water as you have to reach under the filter to turn the petcock. I will not move the line from the pump to the ip and was thinking I could leave the line to the lift pump off then use a compressor and a rag and slightly pressurize the tanks one at a time through the filler necks. And I am not talking about a lot of air here.
 

keithwld

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Actually I just got a better idea for purging the air. I have the electric fuel pump that I pulled off of the frame on my truck. It was unhooked from the lines but was still hooked up to the electric. I will hook it up to the feed line just before the lift pump and turn it on till fuel comes out into a bucket. Seems easy enough. Keith
 

79jasper

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Do not pump through the factory mechanical lift pump.

I figured if disable the ip, it wouldn't pump out the fuel that's in it and take in air.
But I guess probably have to bleed the injectors anyways.

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keithwld

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Do not pump through the factory mechanical lift pump.

I figured if disable the ip, it wouldn't pump out the fuel that's in it and take in air.
But I guess probably have to bleed the injectors anyways.

Sent from my SM-T537R4 using Tapatalk

I already know that which is why I said I would remove the fuel line before the pump and then hook the electric pump before it and pump out the air.
 

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