Wet Filter Causes Lean Condition

[muggzy]

Its definitely not a lean condition if the kill switch stopped it.

 

Get rid of them stock carbs

 

Normally, I hit the kill switch first and it keeps running, then I pull the choke to finally kill it. Last time, I just reached for the choke first (since this is what It's taken in the past to shut her down after the kill switch doesn't do it) and it didn't work. So I hit the kill switch and she did shut down. I'm gonna start methodically troubleshooting this week as I get some time.

 

First I'll try to cause the condition by spraying water into the prefilter covering my airbox ONLY. Then, once I get the "runaway" problem to show predictably under very controlled circumstances, I'll confirm what it takes to shut it off and see what I can figure out from there.

Edited April 24, 2011 by muggzy

[banshee_R1]

I could be wrong but... I think the slides sticking ONLY when its wet would make sense if water vapor was condensing on the slide. Water is a horrible lubricant and may create enough tension between the slide and the carb body to hang it up temopraroly. Maybe try a slightly heavier spring. Or different carbs if your budget allows for it. I personally have never had a problem with any of my Shees but just had a friend have the same thing happen to him yesterday so I need a wat to fix it also

[muggzy]

I could be wrong but... I think the slides sticking ONLY when its wet would make sense if water vapor was condensing on the slide. Water is a horrible lubricant and may create enough tension between the slide and the carb body to hang it up temopraroly. Maybe try a slightly heavier spring. Or different carbs if your budget allows for it. I personally have never had a problem with any of my Shees but just had a friend have the same thing happen to him yesterday so I need a wat to fix it also

 

I just tried to do did some troubleshooting a couple of days ago:

 

While the engine was warmed up and sitting at idle, which was strong and slow, I began spraying my filter from a spray bottle with water. I continued spritzing the filter until it began to race. There was NO throttle movement while this condition was being created; therefore NO sticking slides.

 

Remember, the leak-down test was perfect (I did 7lbs for 7 min+ with no loss of pressure) and so was the compression (145psi ea) a few days ago. So i began looking for a leak in the carb-airbox area: I restarted the engine and while idling normally, started spraying everything in that area with brake cleaner - nothing. If there was a leak, this should have disrupted the idle. It didn't.

 

The guy who was helping me and has years of experience building/servicing banshees (and many other quads), watched as I recreated the condition and while it was racing, reached in and pulled, tugged and twisted both carbs. There was no change in the condition.

 

So his answer was basically the same as everyone elses, don't get it wet. He gave me a stock, undrilled airbox cover and said to take off the snorkle and try running with that for a while. So I still have no answers that are worth a damn.

 

 

Since you've "never had a problem", if you want to help your friend (and me ), and see if this is some sort of "normal" problem that rarely shows up. Get a spray bottle and spritz your filter for a good while until it races or bogs and let us know which way it goes. We all seem to agree that the engine should bog, but I'm beginning to believe that they'll ALL behave this way and it's some sort of phenomena that simply isn't understood.

[muggzy]

Continued this topic on the repairs and mods forum at:

 

http://bansheehq.com/forums/index.php?showtopic=143154