Injection Pump Problem?

79GLIDE

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I believe I have and injection pump problem on my '88 F350. Upon deceleration from highway speed, I've got a serious miss, rough running condition that occurs under light pedal. Idle is a little rough, but no problem under acceleration or full throttle. Return lines have been replaced, and I don't suspect air entrainment. I have run several tanks of donated Jet A through this thing over the past few years, but have rationed in quality 2 cycle oil and conditioner. I'm concerned my pump internals may be suspect. Ideas??
 

Thewespaul

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Yep time for a rebuild, I do rebuild these pumps but be advised I am over a month out right now.
 

79GLIDE

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I've got a spare pump on an '87 6.9 I could put onto the '88 7.3? Want to PM me your rates and logistical details? Thank you!
 

Natehimself36

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Try cracking injectors or locating the miss by listening through a stethoscope or long metal rod / screwdriver. Or a peice of hose. How old are your injectors?
 

79GLIDE

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It's running on all 8 under a load and during acceleration. I recently towed a '93 F350 CC 4X4 250 miles with it. I did replace the return lines a while back and backed of the injector lines to bleed air at that time. Might do that again to be sure. The pump and injectors have 100k miles, so I'm certain the injectors are due.
 

Team Dirt

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I believe I have and injection pump problem on my '88 F350. Upon deceleration from highway speed, I've got a serious miss, rough running condition that occurs under light pedal. Idle is a little rough, but no problem under acceleration or full throttle. Return lines have been replaced, and I don't suspect air entrainment. I have run several tanks of donated Jet A through this thing over the past few years, but have rationed in quality 2 cycle oil and conditioner. I'm concerned my pump internals may be suspect. Ideas??
How much oil and Additive have you been using in the jet a. I have 2 barrels that I’m going to start burning
 

79GLIDE

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I add 1 gallon of quality 2 cycle oil per 50 gallons of jet A, plus the prescribed amount of Diesel Kleen +Cetane. The rotor wing mechanic who ran it in his 7.3PS, too.
 

riphip

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Running in a PS is different than running in an IDI. PS does not have the injection pump. I ran 55gal of jetA in my 6.9 with problems later on. I also added 2 stroke oil, 10-40w oil, DieselKleen, etc but didn't help. My nephew worked at Mountain Air and had some take-out fuel also and gave me to try. Too dry for the IDI pump.
 
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