Got the bike all assembled today, fueled it up, and tried starting it up. Pushing on the starter I could gear it trying to come to life when suddenly BANG!!!! A backfire so loud my ears were ringing 30 minutes later.
Look down after the backfire and what do I see but FIRE! After frantically putting out the flames I searched for the cause.
Turns out the vent hide coming from the top T of my carbs was cracked. So when I had the petcock on prime to fill the carbs gas was dropping out onto the engine. Not sure exactly how it ignited though.
After an extensive search for damage from the 10 second blaze turning up nothing. I cut a new line, clamped it up, reassembled the bike and tried again. This time no gas leaking and the engine fired up in the first few seconds of hitting the starter.
So here I am after a change of pants and a shower, sharing the tale with you. Thoughts?
Sent from my Nexus 4 using Tapatalk 2
:icon_eek: ... dont do it again!!
.. glad you are ok! :thumb:
Possibly vapour igniting from finding its way into your starter motor armature and flashing back to the fuel. Thats about the only way it could happen with a cold engine, but amazing odds to get the vapour ratio right..
Lucky / Unlucky at the same time. glad you didnt get any fuel on you and it was only the bike that got a little burnt.
Im missing some arm hair but nothing serious. I was assuming sparks from the starter motor igniting any vapors that got underneath the cover, but wasn't sure.
No pictures of your bike on fire? The last member who burnt his bike had the courtesy to post pictures of it burning.
(What, too soon?)
Probably some gas down in the starter motor area. You burnt it off so you're good to go now.
Quote from: adidasguy on June 04, 2013, 09:22:04 PM
No pictures of your bike on fire? The last member who burnt his bike had the courtesy to post pictures of it burning.
(What, too soon?)
Probably some gas down in the starter motor area. You burnt it off so you're good to go now.
You know...You're right. Who the hell do I think I am....?
Quote from: PatheticPuma on June 04, 2013, 09:23:22 PM
Quote from: adidasguy on June 04, 2013, 09:22:04 PM
No pictures of your bike on fire? The last member who burnt his bike had the courtesy to post pictures of it burning.
(What, too soon?)
Probably some gas down in the starter motor area. You burnt it off so you're good to go now.
You know...You're right. Who the hell do I think I am....?
Ayrton Senna? :angel:
.. and yeah .. what were you thinking .. no handy phone camera or mini cam/vlog rig running .. just in case something spectacular happened!! .. tut tut tut!! ;)
(https://sphotos-b.xx.fbcdn.net/hphotos-prn1/946095_10201311560054291_141145530_n.jpg)
(yes i saved xune's photo becuase it was worthy of epicness)
Not that is a bike on fire! Not sure if I would have snapped a pic or ran to the lake with a bucket!
HELP!!
Okay. So I thought my fuel leak came from the vent "T" on my carbs. I added the missing vent hose and thought it had stopped the leak. But today when I got the bike started up I started getting fuel drips. Basically when the fuel is flowing, it is leaking. ON and RES are fine as long as the bike is off, and PRI will leak regardless.
Any and all help is appreciated.
If there are any GS experts in the Grand Rapids, MI area willing to give me a hand and drink a couple beers, just say the word.
So when fuel flowing, it spills everywhere.
Carbs over flowing into the airbox? What does the inside of the airbox look like? Wet with gas?
Airbox drain hose missing?
Carb drain screw not screwed in? (Been there - done that!)
Float bowl leaking?
Dry it.
Baby powder it.
Put on PRIME.
Where is gas coming from?
Quote from: adidasguy on June 05, 2013, 04:10:46 PM
So when fuel flowing, it spills everywhere.
Carbs over flowing into the airbox? What does the inside of the airbox look like? Wet with gas?
Airbox drain hose missing?
Carb drain screw not screwed in? (Been there - done that!)
Float bowl leaking?
Dry it.
Baby powder it.
Put on PRIME.
Where is gas coming from?
The airbox is dry, and i tried the the drain screws. The gas seems to be dripping from directly above the bottom T on the carbs. Its just a small steady drip, about 1 every 2 seconds.
If coming from the bottom T, probably a bad seal on the T (o-ring?). If coming from the upper T, which is the vent, one or both float needles is leaking.
Quote from: Paulcet on June 05, 2013, 04:39:10 PM
If coming from the bottom T, probably a bad seal on the T (o-ring?). If coming from the upper T, which is the vent, one or both float needles is leaking.
Hmmm, I wonder why they would have started leaking. I assumed it is something I did during the teardown, but i never got around to even touching the carbs. There was no leak before the disassembly.
Also, apart from simply cleaning out the bowls/jets, I know NOTHING about carbs. How would I fix leaking needles?
The needles can be finicky during float assy install. I have had a set of brand new needles/seats leak when I tried to install them with carbs mounted on the bike. It took 2 or 3 tries. I should have taken the carbs off to install new needles.
Or, your needles could be worn out. They are to be replaced with the seats as a set. If you think the needles and seats are good, you could have a bad seat o-ring. You can replace them by removing the seats.
Would sitting untouched for the winter cause the seals to have problems?
I will have to check out the carb thread...
Sent from my Nexus 4 using Tapatalk 2
Yes, I think so. When I bought my bike from Dgyver, it hadn't been ridden much. Shortly there after, one of the float needle seats had a bad o-ring.
I have a spare set of carbs. I will put them on tomorrow and see if the leak still exists.
Sent from my Nexus 4 using Tapatalk 2
Had a similar leaking problem after a tip over. Turns out the float needle had dislodged. Cleaned carbs while I was at it, put in new O rings and no more leak. BTW, please pass the marshmallows.
Maybe I missed something, but float needles don't cause fuel to leak from the T connection. If it's leaking from there, then you have a bad gas seal on one or both sides of the T, or the T itself is cracked. You have to split the carbs and replace the seals and possibly the T as well. I had to do this on my carbs, and a set of carbs I rebuilt and resold. It's common for those seals to dry out and crack when you rotate the T around while installing the carbs. Also, don't use a metal worm screw hose clamp for your fuel lines, because they put too much pressure and break the T. The PO of my bike had done this.
Fix the leak first, and then move on to checking the float height and adjusting your float needles. If the float needles are leaking, you might get gas overflowing into the airbox, not dripping from the carb T.
Yeah, maybe you missed something Bomb. Lower T, not from leaking needles. Upper T, is from leaking needles/seats.
Quote from: Paulcet on June 05, 2013, 04:39:10 PM
If coming from the bottom T, probably a bad seal on the T (o-ring?). If coming from the upper T, which is the vent, one or both float needles is leaking.
Quote from: Paulcet on June 06, 2013, 10:58:06 AM
Yeah, maybe you missed something Bomb. Lower T, not from leaking needles. Upper T, is from leaking needles/seats.
Quote from: Paulcet on June 05, 2013, 04:39:10 PM
If coming from the bottom T, probably a bad seal on the T (o-ring?). If coming from the upper T, which is the vent, one or both float needles is leaking.
I'm also confused on how a steady drip could come from the upper T. That T is high enough, at least as I remember it, that there should be fuel in the airbox and the carb mouth before it would reach the level of the upper vent T. He says the airbox is dry. I wouldn't think you could ever have a significant drip from the upper T connection, and, if you did, you would have huge problems. I could be wrong on this, so others please jump in if you have experienced otherwise.
So Puma, can you confirm for us exactly where the drip source is?
Quote from: bombsquad83 on June 06, 2013, 12:49:16 PM
I'm also confused on how a steady drip could come from the upper T. That T is high enough, at least as I remember it, that there should be fuel in the airbox and the carb mouth before it would reach the level of the upper vent T. He says the airbox is dry. I wouldn't think you could ever have a significant drip from the upper T connection, and, if you did, you would have huge problems. I could be wrong on this, so others please jump in if you have experienced otherwise.
So Puma, can you confirm for us exactly where the drip source is?
Good point!
Okay it is fixed. Just ran the bike for a solid 5 minutes no drips.
The culprit? BOTH float needles were frozen to the seats. Pulled the seats and needles from the spare carbs and while I was at it I cleaned the carbs and followed the tutorial on float adjustment. Put in new bowl gaskets and reassembled. Hooked everything up and fired her up. Ran better than I have ever heard her run.
@Bombs - I assumed air box was dry since there was nothing come from the drain, in reality the drain had been plugged on the inside and I hadn't noticed. Air box had about a cup of gas in it and both carb mouths were rather moist.
Thanks Paulcet. If you ever find yourself in west michigan, I owe you a beer.
This is how they looked when I pulled them out.
(http://img.tapatalk.com/d/13/06/07/a7ysu2us.jpg)
Sent from my Nexus 4 using Tapatalk 2
Quote from: PatheticPuma on June 06, 2013, 02:25:13 PM
(http://img.tapatalk.com/d/13/06/07/a7ysu2us.jpg)
Oh, yeah. That'll do it!
Good job! I would keep an eye on those gas seals on the T just to be 100% sure. That's one place you don't want gas dripping with a hot engine, as you already well know.
if those orings look like that how did the rest look? the print on the float, the bowl gasket etc.
I am impressed you sourced those orings the same day, I find that hard to do around here.
anyway glad you got her running again! Carbs are more just taking your time to get them apart and clean. they look intimidating at first.
Quote from: PatheticPuma on June 04, 2013, 09:06:14 PM
Im missing some arm hair but nothing serious. I was assuming sparks from the starter motor igniting any vapors that got underneath the cover, but wasn't sure.
heh heh mm heh heh FIRE FIRE FIRE lol. been there. GLAD nothing worse happened. vehicle fires of anykind suck. had 2 happen not too long ago. once on motohuffy when a bolt broke, snagged fuel line pulled it loose and fuel sprayed over hot engine. next to stream so good there. then the goped as well. had line come loose from carb. spraying over engine running at 16k ( quite warm lol) that one put itself out. i ( as im sure you too) make sure this wont happen again. maintenance is one of my OCD's now.
off topic here.. apart from the fire bit...
years ago ... driving truck to Melbourne, Australia... about 11pm on a warmish late spring night... having a ciggie... flicked ash out the window ... the 'red coal' went with it , supposedly out the window too :icon_rolleyes:
mutter mutter mumble .. grab lighter... relight ciggie... 'tum de tum' humming to myself and just enjoying the moment... sniff sniff... i can smell smoke!.. ooh there might be a bushfire or something! ... sniff sniff.... no .. thats not wood burning.. that smells more like a vehicle on fire... hmmm.. cant see anything?.... hmmm .... sniff sniff... actually .. it smells like cotton burning... ummmm.... i can see smoke! ... "golly gee and gosh" that smoke is going OUT through the back edge of my window!! ... brakes brakes BRAKES!!!!... stopped... spin around in the seat to look at the light 'camp bed mattress' that we keep in the space behind the seats (just enough to fold the seats forward and have a power nap while laying down kinda thing) ... part of the mattress cover .. about A4 sized bit .. was merrily smouldering away ... the edge of the smoulder section was just starting to get under my travel bag and out of the buffety wind in the cab now i was stopped it had popped into a little flame about an inch tall.. thwap Thwap THWAP THWAP!!!! .. out out out.. fire out out!!... didnt burn my hands or anything... wasnt big enough flame for that ..
did this one! .. (http://images.wikia.com/brutallegend/images/8/84/Brutal_Facepalm.jpg)
... kept on travelling... kept smoking too... just a whole lot more careful with it.. better window adjustment .. and paid more attention to the whole thing...
about a week later .. a whole semi trailer burnt to the ground not too far from where i was at the time... driver was smoking...
made me feel glad i was lucky with it ...
did i learn?... a little bit ... did i stop smoking .. not yet .. maybe one day .. :icon_rolleyes:
speaking of smoking while driving lol. :oops: driving a nissan 720 aka hardbody 86.5 model. ( 86 was previous edition .5 onwards was the hardbody) anyhoo vinyl seats, manual etc. popped cig out window yeah i know :nono:, while shifting. pass window was open cig leavs drivers side, goes around to pass side and lands under my left leg before i complete shift. needless to say i learned real quick 1 not to do that anymore and 2 learn to stop QUICKLY w/o causing a wreck. ( althewhile burning the underside of my thigh) :technical:
lol.... aint turbulence a Buddha Loves You sometimes!!! ;)
Great stories, Janx101ie, from all over Australia, eh. Melbourne, Tasmania, NSW, amazing. And you're alway a hero. Amazing stories, Let's sit around the campfire under the stars eating a damper, having a beer and a toke, while you tell us more of your AMAZING AUSTRALIAN stories. Can you tell us that AMAZING AUSTRALIAN story from that time you were in Queensland, and then maybe that AMAZING AUSTRALIAN story from the time you were in SA? We are all looking forward to these AMAZING AUSTRALIAN stories....honestly, cross the old heart...
Quote from: cbrfxr67 on June 05, 2013, 08:31:43 AM
(https://sphotos-b.xx.fbcdn.net/hphotos-prn1/946095_10201311560054291_141145530_n.jpg)
(yes i saved xune's photo becuase it was worthy of epicness)
"hey honey take a gander at that! My bikes on fire! Snap a picture and well put it out afterwards" sorry couldnt resist!! If my bike lit up i would be scrounging around for something to put it out :icon_lol: I hope u and the bike are okay and if not then i hope you or the bike gets better!
@cbr is that your bike in flames in the pic?
Quote from: PatheticPuma on June 08, 2013, 12:57:07 AM
@cbr is that your bike in flames in the pic?
No it belongs to another member Xune :thumb: