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Posts posted by jpaz

  1. Ok I may have been mistaken about the bad gas. I think I had run my fuel line too close to the front of the block. I moved it some, but still had some more vapor lock issues. I have now added a 1/2 phenolic spacer and that raised the fuel line and wow! My engine really likes that after I re-tuned  it. I didn’t really hammer it too much, but it is even more responsive than it was. Anyway I’m pretty sure that the fuel percolating is done.

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  2. Wow that’s so long I couldn’t read through it. Ever since I put the headlights on a relay the dash lights have been even brighter than just going to the led lights in the dash. No brainer. Then going to the leds for the headlights, dash lights are brighter than ever!

  3. 1 minute ago, Stanglover said:

    Sounds like you may have it fixed by now, but here are my pics just in case they still may help, It's frustrating as hell I know, been there-done that! I too am experiencing a minor fuel problem. It suddenly started to loose rpm's and stall until it is fully warmed up. It has done this for the last few time I've driven it, just haven't had time to find out why, wifey got me doing yard work! 

    fuel line 2.JPG

    fule line 4.JPG

    fuel line 3.JPG


    Thanks so much Geoff! I do have these pics somewhere. But anyway I did run my line very similar to what you did. I do have a/c, so it was pretty difficult to get the bends right. Now after I moved the line out and away from the front of the block, I hopefully won’t have any more problems. I will try to take a few pics, but with the a/c compressor there it’s hard to see. Anyway thanks again!

  4. 7 hours ago, Stanglover said:

    When I made up my new pump to carb fuel line, I made sure I had a min. 1" clearance from the block. With stock intake, no ram air, there is room for a 1" fiber or phenolic spacer. I did have percolation issues before the exhaust cross over were blocked, but I don't think the B/ thunder has those, do they?

    Pics of my fuel line fix if needed. 

    Mine doesn’t have the crossover. I am pretty sure that most of my issues are because I had the new steel line too close to the engine. I have moved it away now, so hopefully it will be ok. I had a small fuel leak after I started it up this morning, so I sell gotta fix that. Got the part to do it but I won’t get to drive it till tomorrow. 
    I was looking for the pics of your fuel line but I couldn’t find them. I actually tried to go by what you did, but I did put it way to close to the front of the block.

  5. 6 hours ago, Big Red Mach 1 said:

    I have a Blue Thunder. It does have the crossover. I blocked mine with inspiration from Geoff. With ram air, you may or may not get a thin spacer in there unfortunately. At least without modifying the stock plenum. I could not get my Ram Air back in until I went to aftermarket engine mounts and 73 frame mounts which lowered the engine roughly 5/8". Summit sells a 1/4" phenolic spacer. I just bought one.


    Some spacer is better than no spacer.  You may want to pick one up and see if you can fit it. 

    I don’t have ram air and I am going to see if I do have enough room for a spacer. I thought I had one around here somewhere but can’t find it. I’ll just go to my local parts house and get one. It sure can’t hurt. I’m actually surprised I have never had a problem with this before. Combination of it being 90 degrees and switching to a 192 thermostat must also be a factor. 

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  6. 5 hours ago, Don C said:

    Vapor lock occurs between the tank and the fuel pump. Any vapor in the line between the pump and carburetor will be quickly purged when the float opens the needle valve. The fuel pump creates a negative pressure in the line between the tank and pump, which reduces the boiling point of the gasoline, and fuel pumps aren't very effective at pumping vapor Between the fuel pump and carburetor it is under positive pressure.

    Look for places where the fuel line runs parallel and close to the exhaust, and relocate or insulate it. Setting in traffic allows a lot of heat to accumulate under the hood and under the car, exacerbating the problem.

    An electric fuel pump located at, or in, the tank will eliminate vapor lock.

    I have the fuel lines running in the factory positions. The only thing I changed was the fuel pump and line from the pump to the carb, nothing else. I have not had any problems like this till now. I may think about the electric fuel pump, sounds like a good idea.

  7. 3 hours ago, Big Red Mach 1 said:

    You running a spacer under the carb? If so, how tall? 

    No spacer. I’ve never had any problems with vapor lock until this summer. I changed the fuel pump cause it was leaking. I then also made a new steel fuel line. I had fuel injection hose going from the pump the carb, never had a problem. But when I put my new pump on I figured I might as well make a new steel fuel line like it should be. I just got done rerouting it, so hopefully that will do it. If not then I may have to put a spacer on, but not sure about clearance. I have a Blue Thunder intake and it kinda tall. Might have enough for a 1/2 phenolic spacer should need be.

  8. So I had more issues yesterday. Car died on the road again after driving around for awhile. And after opening the hood to let it cool down it started. This happened a couple times and I finally made it home.

    So once back home I started investigating what was going on. I noticed the fuel moving around some inside the fuel bowls. I have clear glass sights and I can see the floats and fuel level. Then I noticed the gas actually percolating in the bowls. Well, dummy me made a new steel fuel line and it must be to close to the front of the block. That’s gotta be what has been giving me issues. I am going to redo it and see if that fixes it. I tried to run it like the stock one, but it must be getting to hot. 

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