Irregular Idle

[acschurr]

I've noticed that my idle speed tends to fluctuate quite badly when coming in from a run to an idle. Up and down, Up and down. Engine is not fully run in yet, and I still have it running a bit rich. Add to this, I'm running Blue thunder first run (loaded with oil). Could these be causing the irregular idle?

-aidan

 

[bomber]

You may have bubbles in your fuel line feeding the carb. I use ArmorAll to kill the bubbles in my maxx. Just use the pump spray bottle, and put two full squirts into a full gallon.

- bomber

 

[Diver6127]

Check for airleaks in the tank and fuel line. Also check the length of the pressure line. Too short and it may also cause pulsing.

 

[Mastec]

Yea, I lengthened mine from 4" to 10" and now it idles nice.

 

[Diver6127]

I learned the hardway also. Instructions called for 10" and i said "WTF, that'll make it look sloppy." So i just made it long enough to reach from the tank to the pressure hole in the pipe. Result, erratic idle and poor fuel delivery becuase of the pulsing. I lengthened it to the suggested 10" and tuning issues were resolved. Go figure!

 

[bomber]

I've only posted this about 20 times, so what will once more matter? I got this link from Olds, but I don't know the author. Great reading though. It talks about fuel/pressure lines near the bottom.

Tuned Pipes

- bomber

 

[SokuShi]

armorall in your fuel? whats that have to do with removing bubbles?

 

[bomber]

Chemistry's cool.