Go Back   ATVConnection.com ATV Enthusiast Community » Brand Discussions Area » Yamaha
Sign in using an external account
Register Forgot Password?
Search

Welcome to ATVConnection Forums!
Welcome to ATVConnection.com.

You are currently viewing our forums as a guest, which gives you limited access to view most discussions and access our other features. By joining our community you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is fast, simple and absolutely free so please, join the ATVConnection Forums community today!


Reply
  #1  
Old 08-18-2013, 07:29 PM
Weekend Warrior
Garage is empty, add now
 
Join Date: Apr 2013
Posts: 22
Default Big bear flooding issue

Well I have been working on my atv all day and still having issues. Somehow the carb is getting flooded no matter what I do. I adjusted the float level to where it is pretty much closed with the float at the lowest point. The atv will start and idle perfect for about a minute, then it starts stumbling and falling on its face and dies. I can then drain the carb bowl and it will fire right up again and idle fine....then in about a minute it will start to stumble. I cannot figure out why it is flooding??!

At ideas on how it is flooding even with the float adjusted really high?
Reply With Quote
  #2  
Old 08-18-2013, 09:09 PM
old polaris tech's Avatar
Polaris ATV Expert
Retired and loving it!
Garage is empty, add now
 
Join Date: Jun 2008
Location: North Texas
Posts: 12,801
Default

Sounds like you need a carb kit that includes the needle and seat. If the needle or seat are worn,fuel can still by pass the float arm filling the bowl up even if the float level is set high.
__________________
Retired and loving it! (Main job now,wake up the wife to go to work!)
92 Honda Night Hawk 750 (5500 actual miles)
2000 Chevy Silverado 1500 Sport side (270,000 miles,semi retired)
Whats right is whats left after you do everything else wrong (Robin Williams) RIP
Don't pick a fight with an old man,if he can't fight he'll just shoot ya!
Reply With Quote
  #3  
Old 08-18-2013, 09:47 PM
Range Rover
Garage is empty, add now
 
Join Date: Nov 2011
Location: State Center, Iowa
Posts: 107
Default

Among other things I think you need to be a little more precise on measuring your float drop. Using a yard stick isn't close enough and being just a frog hair off can make a difference.
__________________
04 Bruin 350 4x4
05 Kodiak 450 4x4
Reply With Quote
  #4  
Old 08-18-2013, 10:03 PM
Weekend Warrior
Garage is empty, add now
 
Join Date: Apr 2013
Posts: 22
Default

I already bought a carb kit and replaced the needle and needle seat. Same issue is happening.

I measured the float height with some digital calipers at .52". At this height the atv wouldn't even idle at all. After I increased the height to around .75" it began to idle for a bit but then it would stumble and die. That's when I could drain the carb bowl and start it again as I mentioned above.
Reply With Quote
  #5  
Old 08-19-2013, 09:15 AM
Weekend Warrior
Garage is empty, add now
 
Join Date: Apr 2013
Posts: 22
Default

Could the main diaphragm be causing the problem? It doesn't appear to have any holes or rips in it, but there might be something I'm not seeing.


Also, what is the stock setting for the float height? .51" from the bowl seat to the top of the float?
Reply With Quote
  #6  
Old 08-19-2013, 02:03 PM
old polaris tech's Avatar
Polaris ATV Expert
Retired and loving it!
Garage is empty, add now
 
Join Date: Jun 2008
Location: North Texas
Posts: 12,801
Default

Still sounds like float related,either sticking or float level if you have a new carb kit and still leaking.Plus don't over look the over flow tube for any splits.Just fill the bowl close to the top and see if it leaks through the tube. Plenty of videos on You tube,plus here's a pdf link to a cheap manual that can show you specifics.Shop Service Manuals - A.T.V.
__________________
Retired and loving it! (Main job now,wake up the wife to go to work!)
92 Honda Night Hawk 750 (5500 actual miles)
2000 Chevy Silverado 1500 Sport side (270,000 miles,semi retired)
Whats right is whats left after you do everything else wrong (Robin Williams) RIP
Don't pick a fight with an old man,if he can't fight he'll just shoot ya!
Reply With Quote
  #7  
Old 08-19-2013, 11:22 PM
Weekend Warrior
Garage is empty, add now
 
Join Date: Apr 2013
Posts: 22
Default

well after doing some more tweaking this evening, I am still having problems but it has gotten a little better. I put the original stock needle back in ( what notch should the clip be in?) and adjusted the float to be at .51" . I also regapped the spark plug (which was black and sooty)

The atv will start up and run good for about 30 seconds but then starts to idle pretty rough. It will get rough enough to almost die. If I slowly give it some throttle it will bog and almost die, then when I get above 1/4 throttle it runs smooth.

I noticed if I disconnect the intake hose from the carb, the idle would smooth out a bit.
Reply With Quote
  #8  
Old 08-20-2013, 08:30 PM
Weekend Warrior
Garage is empty, add now
 
Join Date: Apr 2013
Posts: 22
Default

I tried changing the pilot jet to a 40 and then a 37.5 from the stock 42.5. The atv would still run but very rough with the pilot screw all the way in. I tried the pilot screw from the seated position all the way out to 3.5 turns out. I unhooked the intake tube from the carb and it would smooth out a bit, then I would put it back on and the atv would then stumble and die. I'm at a loss on what to do?! Why would the pilot jet all of a sudden be causing this much of a problem or be that much off? It revs fine from 1/4 - WOT. Just the idle and 1/8 throttle is causing issues.

The other thing I noticed was the fuel shut off does not completely. Fuel still trickles out while in the off position. Could this be causing the issue?

Any help would be greatly appreciated!!
Reply With Quote
  #9  
Old 08-21-2013, 11:55 PM
Weekend Warrior
Garage is empty, add now
 
Join Date: Apr 2013
Posts: 22
Default

I cannot understand why it will idle ( still rough though) when I unhook the intake boot from the carb.... And it will stumble and die when I hook it back up?

When I open the box up or even take the filter out....it won't idle.

I installed a new spark plug and ran the atv around the block and pulled the plug and it was already solid black.

I thought maybe the diaphragm wasn't working, but with the intake boot off, I can see it raising and lower as I give it throttle and let off.

I'm about to give up on this thing. Anyone that can help I would greatly appreciate it.
Reply With Quote
  #10  
Old 08-23-2013, 08:32 PM
Weekend Warrior
Garage is empty, add now
 
Join Date: Apr 2013
Posts: 22
Default

I decided to try a chem-dip on the carb. Well I pulled the carb and stock pieces out of the dip after 24 hours and blew everything off. I made sure everything looked good and clean and started reassembling it all. I got it all back together and on the quad, started her up and she idled kind of high at first. It was a smooth idle, but it was too high for sure. After about 10-15 seconds the idle started to drop. Then it started getting rough again as the quad warmed up. After about a minute or so it got really rough and was struggling to stay running again. Same old thing.....

I pulled off the intake from the carb and it started idling high but it was still really rough and uneven.

This is getting frustrating.
Reply With Quote
Old 08-23-2013, 08:32 PM
Reply

Tags
06, 450, atv, bear, big, carb, flood, flooding, floods, idle, intake, kodiak, runs, start, unhooked



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On