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Backfire, Flames and 2 cylinders
- triggerbilly
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i got the pods on and rejetted the carbs.
I got it started up and idling ok, took it for a quick spin around the block and ....... Ran out of gas (yeah i know, what a dickhead !!!)
anyway i got some more fuel in it and got it started and noticed 1 & 2 cylinders are not firing. This is probably why i'm getting big backfires ?? we're talking flames here !!!
I'm just going out to check the plugs ( i'll let ya know what they are doing)
does anyone have any suggestions to what i should be looking at ?
p.s Where or what do i need to do with the rubber hose that fitted into the top of the old airbox (it's about 1 inch black hose, is it part of the smog system ?
thanks
1982 kz750-e3
1983 cb1000c
plano. TX
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- triggerbilly
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getting a nice blue spark on each plug BUT....
1 & 2 plugs wet and black. 3 & 4 black to dark tan color but dry
1982 kz750-e3
1983 cb1000c
plano. TX
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- timebomb33
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1973 z1 2-1974z1-a,2-1975z1-b dragbikes1015cc+1393cc, 1977kz1000,1978kz1000,1981kz1000j, 1997 zx-11, 2000 z12r,1428turbo nitrous pro-mod and a shit load of parts thats all for now leader sask.,CANADA
I THINK MY POWERBAND BROKE
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- gane
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[img][/img] 1977 KZ1000A1
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- triggerbilly
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just check the fuel lines etc. and as i was pressing the starter switch i noticed fuel being sucked down the hose from the petcock that goes into the top of carb no.2
Is this right, should gas be traveling down that hose (the smaller one)I thought it was a vacuum hose ???????
1982 kz750-e3
1983 cb1000c
plano. TX
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- Patton
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If not already done, would assure valve clearances being to specs. Because too tight intake valve gap can cause backfire through the carb.
Fuel line from petcock does not go into top of carb.
[Click on image for larger view]
Good Luck!
1973 Z1
KZ900 LTD
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- Patton
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1973 Z1
KZ900 LTD
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- Patton
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sounds like a carb problem. as far as that hose goes get a k&n breather filter for it. it is your crankcase breather.
Thinking the crankcase vent hose is usually fitted into bottom of air box, whereas triggerbilly described a hose as going into top of airbox.
1973 Z1
KZ900 LTD
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- Patton
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Just noticed something strange (maybe)
just check the fuel lines etc. and as i was pressing the starter switch i noticed fuel being sucked down the hose from the petcock that goes into the top of carb no.2
Is this right, should gas be traveling down that hose (the smaller one)I thought it was a vacuum hose ???????
Is it possible that the vacuum line from carb to petcock has been accidently attached to the petcock fuel outlet (instead of the petcock vacuum nipple) and thereby allowing fuel to be sucked into the carb vacuum nipple (petcock set in PRI position)?
1973 Z1
KZ900 LTD
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- Patton
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Ran out of gas...got it started and noticed 1 & 2 cylinders are not firing....
Running dry may suck a lot of grit and crud from the tank. If an inline fuel filter isn't fitted, the grit and crud may obstruct the float needle/seat interface, resulting in overly high fuel level in float bowl, causing over-rich mixture, which can flood the cylinder and foul the spark plug.
Good Luck!
1973 Z1
KZ900 LTD
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- triggerbilly
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The thicker of the two tubes running from the back side of my petcock is going to the tee on my carbs (inline filter). And the thinner one on the left as you look at the petcock is going to the top nipple of my number 2 carb.
it seems to be dripping slow and constant on the 'on' 'res' and prime position
(my carbs have been leaking ever since i bought the bike, so I'm guessing this has something to do with it)
the thick tube that was running to my airbox is the hose from my vacuum switch (so it's just hang there at the moment)
maybe a daft question but Is there a way to rip all the vac lines out and block off the nips ?
thanks
1982 kz750-e3
1983 cb1000c
plano. TX
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- triggerbilly
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I've had trouble with them since i bought the bike too.
I've had it running on all four, but they ain't firing at the moment
1982 kz750-e3
1983 cb1000c
plano. TX
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