flameout issues during pit stops.
10-08-2011, 04:34 PM
#1
flameout issues during pit stops.
hey guys i'm having issues with my os vzb vspec pro mod in my mugen mbx6 during pit stops in main events
everytime my pit guys fills it up it wants to flame out or actually does as i pull out of the pit lane.
i've tried tuning left and right but can't seem to figure it out, any ideas?
i also heard slamming the lid shut also causes flamouts, but even when its not slammed the motor still wants to die.
everytime my pit guys fills it up it wants to flame out or actually does as i pull out of the pit lane.
i've tried tuning left and right but can't seem to figure it out, any ideas?
i also heard slamming the lid shut also causes flamouts, but even when its not slammed the motor still wants to die.
10-08-2011, 05:17 PM
#3
hey guys i'm having issues with my os vzb vspec pro mod in my mugen mbx6 during pit stops in main events
everytime my pit guys fills it up it wants to flame out or actually does as i pull out of the pit lane.
i've tried tuning left and right but can't seem to figure it out, any ideas?
i also heard slamming the lid shut also causes flamouts, but even when its not slammed the motor still wants to die.
everytime my pit guys fills it up it wants to flame out or actually does as i pull out of the pit lane.
i've tried tuning left and right but can't seem to figure it out, any ideas?
i also heard slamming the lid shut also causes flamouts, but even when its not slammed the motor still wants to die.
10-08-2011, 05:26 PM
#4
Anything that has to do with the fuel pressure needs to be checked. Leaking tank, bad lid/o ring, pressure tube from pipe and exhaust gaskets could all be suspect.
10-08-2011, 06:07 PM
#5
If you have a different Engine/pipe try that also, if prob still there then its more than likely tank or lines...........
10-08-2011, 07:35 PM
#7
Tech Master
iTrader: (7)
I run a Mugen. My pit man fills it just below the neck and closes it and I seldom ever have a flame out. What he does is before sitting me back down he shakes my truck letting me know to blow it out and then tosses me down pit row while I am on the gas. But filling the tank to full can cause this issue. Also check the seal around the cap it could have some wear and not sealing correctly and check the pressure hose from the muffler to the fuel cap there could be a pin hole or crack in it. best to use the process of eleimation when tring to figure these problems out......
10-08-2011, 08:19 PM
#8
Tech Apprentice
iTrader: (3)
He's filling the tank too full. The fuel tank is pressurized by the exhaust to get the fuel out of the tank and into the motor. If the tank is overfilled and no air gap is present at the top, it can't build up any pressure since the liquid can't be compressed. I run an MBX-6 too, I have to blip it a bit during the stop and make a point to keep the RPM's up for the first 1/2 of the out lap to make sure it stays running.
Don't really know how to fix it though, asking my fueler to try not to fill it over the top is hard, my home track races at night and its all but impossible to see the fuel level until it is coming over the top. I know it wants to die, so I do my best to prevent it during and after the stop by working the throttle differently.
Don't really know how to fix it though, asking my fueler to try not to fill it over the top is hard, my home track races at night and its all but impossible to see the fuel level until it is coming over the top. I know it wants to die, so I do my best to prevent it during and after the stop by working the throttle differently.
10-08-2011, 11:53 PM
#10
+1 on checking the tank because if there is a leak it would cause it to lose pressure and causing no fuel getting to the engine. I had a clunk on my truggy go and had to take the clunk and the fitting out and didn't tighten it back up properly and had flame out after flame out and tightened it back up properly and not problems after. I would check the fitting out, all o-rings(lid and fitting) and do a pressure test basically put clean fuel line(exhaust side inlet side and the fuel outlet end)on it and plug one end submerse the tank in water and blow threw the other end and if you see any bubbles coming out you have a problem but if there isn't any the tank is good and can move on to other problems.
11-07-2011, 12:28 PM
#11
I run a MBX-6 and have not had a flame out all season.
1. Run a 11" pressure line
2. Rev the engine right before he opens the cap then let it Idle while it is being filled. When he closes the cap rev it again. ( the reason for Idling during the stop is so the exhaust pressure will be low allowing fuel to go into the pressure line instead of the engine when the cap is closed).
3.Make sure the idle gap is between .5 and .7 millimeter, then set the idle speed using the low speed needle. I think this is the most important step in preventing flameouts.
1. Run a 11" pressure line
2. Rev the engine right before he opens the cap then let it Idle while it is being filled. When he closes the cap rev it again. ( the reason for Idling during the stop is so the exhaust pressure will be low allowing fuel to go into the pressure line instead of the engine when the cap is closed).
3.Make sure the idle gap is between .5 and .7 millimeter, then set the idle speed using the low speed needle. I think this is the most important step in preventing flameouts.
11-07-2011, 12:37 PM
#12
your low speed needle is too rich... period
11-07-2011, 01:31 PM
#13
Yep
Rich lowspeed is most likely the issue, but those p3 plugs are really thin, and can go bad pretty fast. I would use a p4 in an OS engine just to be sure the plug stays healthy longer...and even try removing the thin shim in the engine, sometimes that helps...
11-07-2011, 01:32 PM
#14
11-07-2011, 01:41 PM
#15
or too cold plug.