Fuel in air filter part 2

Post your Kettle problems here and cures
Mr Bonehead
Posts: 272
Joined: Fri Jul 01, 2011 9:28 am
Location: Rural France/originally from Leeds

Fuel in air filter part 2

Post by Mr Bonehead »

Back again,just had the refurbished carbs off to check that the float isn't stuck and it moves freely,ran the bike without the air filter box and can see mist when ticking over coming out of the air inlet in the center pot,the engine tone revs slightly higher then drops and the mist appears,the engine sounds and runs the same with or without the ht lead on the center pot but there is a spark but the center exhaust pipe isn't very warm and the silencers are cold unlike the ones for the other two cylinders,could this be a crank case seal problem ?
I took a short video but am unable to load it onto the site
Cheers MrB
Update,just had baffles out and soaking wet,could there be too much two stroke oil going into the middle pot or does the pump distribute it evenly between the cylinder ?
User avatar
canaletto5
Posts: 5228
Joined: Tue Jul 23, 2013 8:43 pm
Location: Derbyshire

Re: Fuel in air filter part 2

Post by canaletto5 »

Sounds like weak spark. have you swappped spark plugs and checked the condensors?
Mr Bonehead
Posts: 272
Joined: Fri Jul 01, 2011 9:28 am
Location: Rural France/originally from Leeds

Re: Fuel in air filter part 2

Post by Mr Bonehead »

canaletto5 wrote: Sat Apr 17, 2021 1:27 pm Sounds like weak spark. have you swappped spark plugs and checked the condensors?
Hi caneletto,swopped plugs around put new one in center pot and got new plug caps with 5k ohms reading,if you run the bike and rev it mist comes out and fuel starts to appear in the bottom of the rubber air inlet but when you remove the ht lead and run the bike and rev it a few times then remove the plug the plug is fuel free ,the residue on the baffles is just oil I think ,I've just had the carbs refurbished
It's got a boyer brandson electric ignition on ,not points
User avatar
canaletto5
Posts: 5228
Joined: Tue Jul 23, 2013 8:43 pm
Location: Derbyshire

Re: Fuel in air filter part 2

Post by canaletto5 »

Not electrics then by the looks.If the pot is dry but unburnt fuel is building up before the carb then it sounds almost as though soemthing is stopping the fuel getting through. Have you double, doubkle checked the carb diaphragm for holes,splits? They can occur any time. Kev
Mr Bonehead
Posts: 272
Joined: Fri Jul 01, 2011 9:28 am
Location: Rural France/originally from Leeds

Re: Fuel in air filter part 2

Post by Mr Bonehead »

canaletto5 wrote: Sat Apr 17, 2021 2:03 pm Not electrics then by the looks.If the pot is dry but unburnt fuel is building up before the carb then it sounds almost as though soemthing is stopping the fuel getting through. Have you double, doubkle checked the carb diaphragm for holes,splits? They can occur any time. Kev
Hi Kev,I've revved the bike with the air box off and I can see the vacuum lifting up the needle ,if you put your hand near the air intake you can feel air being sucked in but when you rev you can see the fuel misting and collecting in the bottom of the rubber
Cheers MrB
User avatar
canaletto5
Posts: 5228
Joined: Tue Jul 23, 2013 8:43 pm
Location: Derbyshire

Re: Fuel in air filter part 2

Post by canaletto5 »

Are the exhausts/downpipe clean and clear? If clogged in any way the back pressure could be a problem?
Mr Bonehead
Posts: 272
Joined: Fri Jul 01, 2011 9:28 am
Location: Rural France/originally from Leeds

Re: Fuel in air filter part 2

Post by Mr Bonehead »

canaletto5 wrote: Sat Apr 17, 2021 2:18 pm Are the exhausts/downpipe clean and clear? If clogged in any way the back pressure could be a problem?
You can feel air coming from both rear silencers for the middle pot when running and also on tick over see what I assume is unburnt 2stroke oil coming out ,I'm quickly falling out with this bike !!!
User avatar
canaletto5
Posts: 5228
Joined: Tue Jul 23, 2013 8:43 pm
Location: Derbyshire

Re: Fuel in air filter part 2

Post by canaletto5 »

Some air will escape, even on clogged pipes. A quick way to check is to undo the collar on the down pipe and pull it slightly free. Brutally noisy but as your'e in the middle of nowhere you'll only frighten yourself
Mr Bonehead
Posts: 272
Joined: Fri Jul 01, 2011 9:28 am
Location: Rural France/originally from Leeds

Re: Fuel in air filter part 2

Post by Mr Bonehead »

canaletto5 wrote: Sat Apr 17, 2021 2:47 pm Some air will escape, even on clogged pipes. A quick way to check is to undo the collar on the down pipe and pull it slightly free. Brutally noisy but as your'e in the middle of nowhere you'll only frighten yourself
Hi kev,just removed the center piece of pipe (the one into two part),totally off and No blockage
It's a mystery
User avatar
canaletto5
Posts: 5228
Joined: Tue Jul 23, 2013 8:43 pm
Location: Derbyshire

Re: Fuel in air filter part 2

Post by canaletto5 »

Have you tried to run it with the pipe off?
Post Reply