Fuel Line Repair at TBI

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JT58

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I have an 87 350 with the factory TBI set up. I replaced the valve covers this past weekend and was cleaning around the TBI and noticed that the fuel supply line at the TBI is extremely crimped- like it twisted when someone tightened the nut when they secured it to the TBI. The truck runs well, I am surprised it even runs with how crimped the line is. Ok how to repair it? Rock Auto and NAPA only sell a portion of the fuel line that connects to the TBI- 16 MM X 1.5 pitch connector with 3/8 steel tubing 18" long. How do I connect it to the steel line that is there? Cut the line, cut the 18" long tubing very short and splice it with a Straight Union 3/8 to 3/8? Is there enough room for that? Or can I splice it with a very small section of fuel injection hose with 2 clamps each side? I searched for a complete new fuel line, found Classic Tube sells a complete set of fuel lines, I only need one. And even if I purchased all of them will I be able to snake the one and install it with it being pre-bent? Any other suggestions?
 

RanchWelder

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Click on my logo and search for WarHawk in the search or my posts.
The fuel line repair thread there is where to start.

It's "impossible" to snake the lines in without completely removing the TBI or bending the lines, in my experiance.
You would be best served to pull the TBI and Distributor, rebuild either or both, as needed.
Freshen the TBI injector o-rings, screens, accelerator pump and all the gaskets.

The ACDelco kit, with the most parts is the one you want. $36.00 or more, not the cheap kits.
The options for fuel lines and the tools are in the WarHawk thread.

Email me if you have any questions. Happy to assit.
 
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87gmcburb

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Ranch is correct about pulling the TBI, I would avoid "patching" the hard lines and get new ones. Once the TBI and the distributer is off it is not hard to fish them down to the frame rail where they attached to the hard lines
 

mtbadbob

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I'm in the same boat, po cut the kink/twist out of line & spliced with a short piece of rubber fuel line. I may install a new hard line this spring. Little idiocies like that drive me crazy!
 

1STLS1

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I am going to add my .02

Those fuel lines are 37 years old, I think it's cheap insurance to replace them because nothing good happens once they start leaking. They may be stainless steel braid on the outside but the inside is still rubber or a material that deteriorates.
 

JT58

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Ya I'm with you guys on replacing all of the lines. I just can't at the moment, tapped out for a few months. I am going to buy the new lines, have a shop do some major work for rear main leak (I think- and that another shop already did that I would not bring it back to) and at that time have them pull the distributor, TBI, etc. and replace the lines. It will probably be a 4K bill that I will have to swallow. Oh well. In the mean time I don't know if it is better to try and splice the line for now or just keep running it with the line 80% crimped and what damage that will do.......
 

JT58

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I did find that Doorman makes a high pressure Straight Union 3/8 to 3/8 steel connector- part number 800-205. It can be ordered through any auto parts store although it is not stocked. Any hardware store sells a brass unions but they are not for steel lines. I wonder if there is room to get it in there to install the Doorman one and tighten the hex nuts?
 

JT58

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Update on this for anyone that ever has the same issue. I was successfully able to install the Doorman partial fuel connector. It fit the TBI connection perfectly, I was able to use a tubing bender and place a 90 degree bend on the tubing , cut it and I put in a short section of fuel injector tubing- about 8" to couple existing fuel line to the new fuel connector line. It was quite a job though- took me about 8 hours. I had to get in the engine bay, remove a coolant connector at the back of the manifold, remove the coil and distributor cap just to give me access to the lines. I then had to cut the main line with a mini tubing cutter. I then was barely able to get in a flaring tool to flare the end of the existing line. I then flared the end of the new tubing connector- put the fuel injection tubing in and used proper fuel injection clamps. It fit nice and looks professional and no leaks. I had to relocate one of the coil mounts to clear the larger fuel injection tubing and had to fabricate a bracket extension. This is all temporary until I can get in a new fuel line.

The punch line is what a difference it made in the performance- the truck was starving for fuel- I don't know how it even ran. I was not expecting such a drastic difference. It runs and idles so much better now. I took it for a test drive and it had so much power I almost rammed into a flat bed truck parked on the side of the road I had to go around right near my house. I mis judged and almost was not able to turn fast enough. I have adjusted to the power now and love it. The 1974 engine with 1987 TBI and electronics is a powerhouse to say the least now.
 
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Great thread with valuable info. I've converted TBI trucks to carb but never considered using TBI on an older engine. Won't be long before this forum has provided me more useful information than the rest of the internet in it's entirety.

Great job getting it fixed yourself.
 

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