Fuel in air filter part 2

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Mr Bonehead
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Re: Fuel in air filter part 2

Post by Mr Bonehead »

canaletto5 wrote: Sat Apr 17, 2021 3:00 pm Have you tried to run it with the pipe off?
I've just put it back on,there's plenty of air and oil fumes coming out of the bottom rear pipes that are for the center pot,I've had the baffles out and they're clean apart from oil residue ,it ticks over for a while then stops unless you rev it and when you do it to 4000 rpm it just blows out misty unspent fuel into the air box rubber
teazer
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Re: Fuel in air filter part 2

Post by teazer »

Starting to sound like a pipe blockage as canaletto suggested. If possible, remove the two small mufflers and leave the header on and try running it that way.
Mr Bonehead
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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 »

teazer wrote: Sat Apr 17, 2021 4:17 pm Starting to sound like a pipe blockage as canaletto suggested. If possible, remove the two small mufflers and leave the header on and try running it that way.
Hi Teazer,that's my next job,already had the center down pipe off and taken the baffles out so going to take the two pipes off ,remove baffles again and see if anything drops out when I give them a shake ,might try running without baffles in first but they are like New ,
Cheers MrB
arthur
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Re: Fuel in air filter part 2

Post by arthur »

Hi just reading your post
I had the almost same problem with my 380, Turned out to be a clogged exhaust pipe I pushed a length of bar inside and a big chunk of carbon fell out 4 cm in diam and a bore of 1 cm ( restricted I think)
no wonder she wasn't breathing right .
I chased this problem for weeks carbs off and on
plugs in and out and changed
Timing checked several times
Sometimes we get to caught up worrying about the big things and overlook the simple things
I must say however without the input of the forum I would still be in the dark on lots of stuff :D
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Chris57
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Re: Fuel in air filter part 2

Post by Chris57 »

Hi MB, totally agree that it's worth pulling the inner silencers off and try running the bike without them and checking for anything blocking the header too.
If that doesn't prove to be fruitful then a couple of things you've mentioned such a cold centre header pipe and no fuel on the plug if run without HT lead to me suggests, despite being refurb'd, a possible blockage in the centre carb as they're sunsabee's to clean properly.
Have you done a compression/leakdown test ?
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 »

arthur wrote: Sat Apr 17, 2021 9:14 pm Hi just reading your post
I had the almost same problem with my 380, Turned out to be a clogged exhaust pipe I pushed a length of bar inside and a big chunk of carbon fell out 4 cm in diam and a bore of 1 cm ( restricted I think)
no wonder she wasn't breathing right .
I chased this problem for weeks carbs off and on
plugs in and out and changed
Timing checked several times
Sometimes we get to caught up worrying about the big things and overlook the simple things
I must say however without the input of the forum I would still be in the dark on lots of stuff :D
Hi Arthur,thanks for the reply ,had silencers and down pipe off,baffles are clean and there's no blockage,you can easily blow through the pipes ,just full of 2stroke oil
Cheers MrB
Mr Bonehead
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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 »

Chris57 wrote: Sun Apr 18, 2021 8:52 am Hi MB, totally agree that it's worth pulling the inner silencers off and try running the bike without them and checking for anything blocking the header too.
If that doesn't prove to be fruitful then a couple of things you've mentioned such a cold centre header pipe and no fuel on the plug if run without HT lead to me suggests, despite being refurb'd, a possible blockage in the centre carb as they're sunsabee's to clean properly.
Have you done a compression/leakdown test ?
Hi Chris57,had exhausts of from center pot ,baffles clean,no obstruction,you can blow down them and there's no resistance,had a piece of bar down from the rear and sean it at the front so a 'll ok there ,next thing will be compression test when I can get out to get one ,we are on a 10 km travel limit at the moment,there is pressure but don't know how much as I've only pushed my finger over the spark plug hole .
Cheers MrB
Ps ran the bike without the silencers on ,just the down pipe and still the same(no blockage in down pipe )
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canaletto5
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Re: Fuel in air filter part 2

Post by canaletto5 »

You may be back to basics on this. If the problem is still excess fuel then I would recheck the float operation/height including the float needle valve, it may not be sealing properly.
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Harrymail
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Location: East Yorkshire

Re: Fuel in air filter part 2

Post by Harrymail »

Many aftermarket needle valves have a stiffer spring than mikuni. Engine vibration can cause these to let fuel past and then flooding occurs.

Paul
Currently without a GT, but looking
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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: Sun Apr 18, 2021 2:58 pm You may be back to basics on this. If the problem is still excess fuel then I would recheck the float operation/height including the float needle valve, it may not be sealing properly.
Hi caneletto5,had a phone chat with Baz and did a test he suggested,took carbs off and spark plugs out then put my hand over the inlets to check suction,right hand is strong but the center and left are very weak so sounds like the crank seals :cry:
Thanks for all your advice
Cheers Mr B
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