no vaccum on carby

MightyBoy tech questions and answers.
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Brayden
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Even if you remove the carby completely the motor shouldn't "free wheel" as if it has no compression. The only two causes of that are removed spark plugs or valves not closing.
F8B EFI turbo - Three pots and a snail.
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Jermaine
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Location: Legerwood (tasmania)
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somethin hasnt dropped down the intake and holdin a valve open? but that woul only cause it on one cylinder..
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me217
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no nuttin dropped i put a rag ova the hole while i had the carby off. and i didnt drop anything down there when i did it.
me217

1985 suzuki mighty boy : mods, f8b
1990 toyota mr2 gt import : mods, turbo timer, short shifter, 2.5" exhaust
1992 suzuki sierra : mods, g16b mpfi, 235's/75, snorkel & lift on the way.
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me217
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Location: maryborough, qld
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also i never tried spinnin the engine ova without the carby on so i dunno if it did it then. thats why my guess is that the carby has a leak to the outside. and when i cover the top with my hand it just draws it thru the leak.
me217

1985 suzuki mighty boy : mods, f8b
1990 toyota mr2 gt import : mods, turbo timer, short shifter, 2.5" exhaust
1992 suzuki sierra : mods, g16b mpfi, 235's/75, snorkel & lift on the way.
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Brayden
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Location: Canberra ACT
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It would want to be one hell of a leak to not have any suction at the top of the carby. (ie. A hole the size of a 50c coin)
F8B EFI turbo - Three pots and a snail.
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me217
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Location: maryborough, qld
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yeah, but thats the only thing i can think it could be. as thats all thats changed. unless its lost compression over night.
me217

1985 suzuki mighty boy : mods, f8b
1990 toyota mr2 gt import : mods, turbo timer, short shifter, 2.5" exhaust
1992 suzuki sierra : mods, g16b mpfi, 235's/75, snorkel & lift on the way.
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Jermaine
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Joined: Tue Jan 24, 2006 8:49 pm
Location: Legerwood (tasmania)
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wierd things can happen! i would be either sprayin start ya bastard into it, or checkin your compression
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me217
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fixed the compression problem. it turns out wen my father assembled the carby the pin that holds the float in place had slid out abit and it was holding apart the top and bottom of the carby so there was about 3 mm gap there. so i pulled the carby apart and fixed it up. now thats all good. but its still wont fire. b4 i cleaned the carby it would sometimes start and then die but wouldnt go ova an idle. i i might replace the condenser and points again. and see what happens.
me217

1985 suzuki mighty boy : mods, f8b
1990 toyota mr2 gt import : mods, turbo timer, short shifter, 2.5" exhaust
1992 suzuki sierra : mods, g16b mpfi, 235's/75, snorkel & lift on the way.
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me217
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Joined: Mon Jul 31, 2006 11:01 pm
Location: maryborough, qld
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even start ya bastard didnt make it fire.
wen i first fitted the carby it had a cough like it tried to fire but that was it.
me217

1985 suzuki mighty boy : mods, f8b
1990 toyota mr2 gt import : mods, turbo timer, short shifter, 2.5" exhaust
1992 suzuki sierra : mods, g16b mpfi, 235's/75, snorkel & lift on the way.
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Billie
Posts: 2692
Joined: Mon Aug 17, 2009 9:18 pm
Location: Brisbane

If it turns out to be your carbie, you can have my old one, it works, just secondary is broken. It'd at least get it started.
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me217
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o ok. i dont think it the carby it seems to b working fine. its gotta be electrical cause its not even firing
me217

1985 suzuki mighty boy : mods, f8b
1990 toyota mr2 gt import : mods, turbo timer, short shifter, 2.5" exhaust
1992 suzuki sierra : mods, g16b mpfi, 235's/75, snorkel & lift on the way.
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Billie
Posts: 2692
Joined: Mon Aug 17, 2009 9:18 pm
Location: Brisbane

Does the starter motor work?
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Brayden
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Location: Canberra ACT
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Forgot to connect something to the coil/dissy?
F8B EFI turbo - Three pots and a snail.
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Jermaine
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Location: Legerwood (tasmania)
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yea i would be checkin spark, from the leads or form the coil
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me217
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Location: maryborough, qld
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ok got it started after a bit of fiddling with timing. it idles and revs fine just has one hell of a flat spot and a little miss on idle.
me217

1985 suzuki mighty boy : mods, f8b
1990 toyota mr2 gt import : mods, turbo timer, short shifter, 2.5" exhaust
1992 suzuki sierra : mods, g16b mpfi, 235's/75, snorkel & lift on the way.
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