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Discussion Starter #1
I have a '95 s10 with fuel leaking on to the exhaust manifold. Checked with the engine running, saw drops of fuel dripping onto part of the exhaust manifold. This is near where manifold connects to the rest of the exhaust. I checked for fuel leaking down the fuel lines at the intake manifold, they were dry.
 

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To those in the know... When the fuel lines leak inside the manifold, where does the fuel go? It must have some way of getting out of the lower intake. It would appear to be a closed and seperate system from the air intake. Are the poppets so loose fitting that the fuel leaks past the poppets? Or can it fill the lower intake and be forced out between the upper and lower intake. What about the incoming fuel lines...can fuel leak back out past the incoming lines? I know zero about this type of system and am trying to help B95 figure this out. Time is of the essence.
 

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First guess, you need to check the fittings connecting the fuel lines to the nut kit on the back of the lower intake manifold. That sounds like the location where B95's leak is coming from. Also, pop off the black cap on the test port on the supply line; is it wet? The Schrader valve in the test port could have failed, filling the cap and deflecting down towards the exhaust. It's a Schrader valve just like a bike tire. If it failed, bleed whatever pressure is on the line with a rag or by running the truck and pulling the fuse/relay for the fuel pump. Then change the valve just like a bike tire. The black cap can be seen in the upper right of the picture below.


As for Rhot's question, fuel leaking from the nut kit or the cpi will puddle in the lower intake manifold; most commonly in the area right under the entrance of the nut kit at the back if the intake. I'm unsure of the total volume it can hold but the lower manifold is 1.75-2" deep in most spots before the marriage gasket for the upper intake manifold. It would have to have been leaking heavily or for a long time to fill that much area. Some of it will naturally evaporate but I don't know where it could go other than eating the gasket material to get out. The nut kit is only sealed in with o-rings; if the LIM has a great deal of fuel in it, that's probably the easiest spot to eat its way out. The air runners are sealed from the throttle body down. The poppets all have rubber seals but those could probably degrade enough to allow fuel to seep into the cylinder. If they are degraded and there is a lot of fuel puddled, I'd be worried about a stray spark getting through. The plastic clip of the poppet probably helps prevent that from happening.


Pull the plugs and check the condition of the electrode. Running too rich?


Other symptoms:
http://www.onallcylinders.com/2012/12/20/reading-101-how-to-read-your-spark-plugs/
 

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Discussion Starter #5 (Edited)
I checked with my hand to "see" if any of the fuel line connections on the back of the intake manifold were wet. They were dry. I used a inspection mirror and a flashlight to further check the lines. When the engine is running, I saw with the use of the inspection and flashlight, a small spray of fuel. The spray of fuel was very fine and just above the driver's side of the frame. I have jacked the truck up and checked under the truck. Only to find fuel dripping off of the exhaust manifold (where the manifold connects to the exhaust tubing). I am thinking it might be the fuel line leaking. The car carrier truck will be here Wed. to haul my truck to Nj. So, I would like to have the truck running better before then. I have had the Spider injection previously replaced. My schrader valve has no cap on it.
 

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Is the top of the transmission wet with fuel?

At the point where the hard fuel line comes off the frame under the DS floor, it turns to a flexible line. The rubber line goes up to the top of the transmission and then to the nut kit connections. If it's leaking from the flexible line or the hydraulic style compression between the two lines, it's pretty much effed. There's no easy way to reach/service that part of the line as it was assembled before the body was married to the frame.

My suggestion if it's that flexible line: grab a few feet of braided stainless steel hose, a flaring tool, a compression fitting that converts to AN, and the proper AN fittings to attach to the nut kit. Reroute the fuel line with braided hose up the firewall and keep it as far from the y pipe as possible.
 

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Pre-bent lines, including the flex lines are available from the filter forward from rockauto for a little over $100? Time is a factor though.
 

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Hmmm. I'm unsure but that kit may be just from the tank pump to the filter on the framerail. Some places have it titled as REAR kit. The flex lines at the front of the body should be a bit longer I think. 425A comes with a very long hard line that I think is the framerail 5/16" vent line.

It's been awhile since I messed with them but from the tank forward you have:
Pump
Flex Line
Hard Line on framerail
1 Filter on supply, 1 solid Hard Line for Return, 1 solid line for vent
Hard Line on framerail
Flex Line kicks in right by front body mount, goes to top of trans
Hard Line connects somewhere and makes the bends into the nut kit - Vent line is on DS of motor hooking into a box that's mounted above the valve cover.
 

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Discussion Starter #11
I noticed the fuel line seems to just disappear around the bellhousing. Rhotpursuit, I may go the route you suggested, but like Tealtank said, it doesnt appear to be a easy job to do, either way. I do appreciate the help guys.
 

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It may be faster to go to the bone yard and get lines out of a truck with the engine already removed if there us one that hasn't been hacked. I've never had to replace fuel lines so I'm shooting like a gangsta...
 

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Discussion Starter #13
But would going to the junkyard and getting a line from there be a good choice?
 

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Once it's out you can give it a closer look and check for chaf marks. You can also see how it's routed. Unless the local parts stores have them, it's quicker than waiting for rockauto. Is it possible to delay your departure until sat-sun to give you a little more time?
 

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Discussion Starter #15
Can't delay departure. Its not just the situation on this end. And we have rain here, so going to the JY is not an option right now.
 
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