1972 Cutlass Supreme - 350 Small Block - 4 Barrel Rochester Carburetor

I recently installed a new OEM fuel pump on my Cutlass and as a result, I replaced the steel fuel line that runs from the fuel pump to the carburetor. When I go to start the engine, the fuel pump works perfectly, but fuel leaks out the new fuel line. I applied some Permatex thread sealant on the threaded part when tightening the threaded part.

The fuel appears to be leaking out the middle of the fuel line, between the steel line and the threaded part. I have attached a picture below with an arrow pointing to where I believe it is leaking from. Does anybody have any idea on how to solve the leaking issue? I bought the the fuel line from OPGI, which should be as close to factory original as I can get.




Thanks!

 

The flare is likely bad or its cross threaded?. Or it's not seated into the mating surface well. Try taking a line wrench to it, losing it, separate it, inspect for galled surfaces, crossed threads or a cracked flare. If it looks ok, assemble it with a line wrench and crank it back n forth a few times to "seat the flare then do a final torque. Doesn't need to be too tight so don't over torque it. If that does not cure it you need a new pump to carb line and or a new carb filter fitting. Both are available. The line can be massaged to make it more "square" to the carb fitting by slight tweaks. The line looks like its offset a bit. So a little tweak could do it if its not damaged.

 

Thread sealant or Teflon tape will not work on a flare fitting because that is not the sealing surface. As suggested, loosen and retighten and then tighten a bit more. Hopefully you'll get it to seat.

 

Thanks guys! Ill have a go at re seating it!

 

When you loosen it, apply a drop of oil between the tube nut and the tube and also on the threads of the tube nut. In most cases the friction between these surfaces prevents clamping the flare fitting properly. This is why despite the (correct) claims that thread tape will not work, folks swear that it stops the leak. In actuality, the thread tape acts as a lubricant allowing the nut to be tightened more. A few drops of oil works great, especially on stainless lines.

 

I leave the carb bolts loose and snug the fuel line up and then tighten all. Works for me

 

Be carefull and make sure you don't strip the threads in the carb, back up the fuel filter with a wrench- ask me how I know!

 

I made my own line from steel tubing from the auto parts store, when I cut and double flared it, there was a tiny seam (parallel to the tubing) from where the tubing was rolled and put together that caused a leak where the flair seats against the fitting. you got to look real close.

 

DOH! Why didn't I think of that. That's a great idea!

 

All Excellent advice.