440 Kioritz help, please!

[Oldsleds]

OK, my 77 440 Liquifire has got me stumped. It starts fine and idles and i can rev it up with the belt off. The problem is when i try to drive it. It takes off then bogs out badly and almost dies. I have tried two sets of carbs, new fuel lines, new fuel pump, new plugs, new gas. It ran good last fall but not now. Now here is the strange thing, when i drive it and it dies if I flip on the choke it takes off and runs great for about 2-3 secs before dieing out again. Now I am sure its not getting fuel to the engine or something but the pump is working great and the carbs are clean and lines and fuel is new. I thought maybe i had a bad air leak but spraying around the intake and seals does nothing to chnge the idle. Could i be loosing spark on one side at higher rpms? Any and all advice would help, really starting to bug me a this point. I see i posted this in the wrong spot, how can i move it?

[lwb140]

change the crank seals !! it is the only thing left , bad seals will cause all kinds of goofy problems most common lean running conditions because of vaccuum leaks and or fuel pumps not pumping because of poor pulse , its a pain to do and requires an afternoon of work but will save your motor , wade

[JDT]

I agree with Wade. Crank Seals.....

[Oldsleds]

ok, i will do that, i will keep you posted on the results. it must be the mag side becasuse spraying carb cleaner around the clutch side does not change idle speed.

[harleysportster]

Did you change both fuel filters?

[Oldsleds]

Yes they are both new, along with new premium fuel.