[mikey007]

(Mods feel free to delete this post or move the one in the general section - I just felt it would get more indy owners here!)

My 1986 indy 400 has great spark, new plugs, new gas, clean carbs, seemingly good compression without tester (blows thumb off of cylinder hole), fuel is getting to the carbs, and new lines. The top end was recently rebuilt and it has not ran since the rebuild due to lack of time to put it together so it was given to me. I cannot get this sled to fire for the life of me. I can pour gas into the cylinders and it will sometimes backfire and throw flames out the y-pipe. Now, I did install the needle jet wrong as it is lying ON TOP of the plate instead of under it. Would this cause my problem? I thought even with carbs put together wrong it would still fire with gas in the cylinders.

Any ideas?

 

[coyote55355]

had the same problem with an old 440 it turned out to be electrical problem of some kind but cant remember exact problem

 

[mikey007]

Did your sled have spark? I can't see why a sled would not fire if it had gas in the cylinders and spark! I guess it could be timing, but I know the timing is okay.

 

[Hangman]

(Mods feel free to delete this post or move the one in the general section - I just felt it would get more indy owners here!)

My 1986 indy 400 has great spark, new plugs, new gas, clean carbs, seemingly good compression without tester (blows thumb off of cylinder hole), fuel is getting to the carbs, and new lines. The top end was recently rebuilt and it has not ran since the rebuild due to lack of time to put it together so it was given to me. I cannot get this sled to fire for the life of me. I can pour gas into the cylinders and it will sometimes backfire and throw flames out the y-pipe. [highlight=yellow]Now, I did install the needle jet wrong as it is lying ON TOP of the plate instead of under it.[/highlight=yellow] Would this cause my problem? I thought even with carbs put together wrong it would still fire with gas in the cylinders.

Any ideas?

That will probably flood it instantly. Instead of just pulling fuel from the pilot circuit, it's pulling from the mains too. Is there crankcase drains on that one? Lower front of engine. If the crankcase is flooded, you'll never get it started. If there's plugs, pull them out, along with spark plugs and pull over many times to dry it out, then try again.

Also, check to make sure your choke plungers are seated.