"Buck" Rogers, bucking and dying.

[clarkfish]

Hey all,

Still a newbie here. Here's the scoop. 1978 FJ40, 2F w/header and Weber 32/36 carb. Take her for a drive, she does fine at all speeds, idles well, accelerates well. No problems for about 30-45 minutes. Starts fine and all that stuff. After about 45 minutes of driving, She starts to buck and will either die or I can possibly coast w/ clutch in and she will start to idle and run. Here are my questions. Can the fuel line get too hot and vaporize fuel? I have had this problem w/ gas cap on and off, so I don't think I am pulling a vacuum or vapor locking the tank. I don't have this problem on short trips and after she cools off, I don't seem to have this problem. Only after the magical 45 minutes of driving. I am considering ditching the header and throwing my old carb back on. Any and all advice, ridicule, and pointers are welcome. Thanks

 

[Pin_Head]

Sounds like fuel starvation. It could be "vapor lock" but it is unlikely, especially in winter. More likely junk/rust/dirt in your fuel tank or something clogging the line or filter.

 

[clarkfish]

Thanks Pinhead, I have been running that issue down. I guess I should have mentioned that it happens when I get to about half tank of fuel. I guess it could be grabbing crap. Your posts have helped me several times. Again thanks and I keep you posted.