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CC rochester fuel leaking from the top

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Old 07-11-2011, 02:03 AM
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CC rochester fuel leaking from the top

hello, i just got this ride(86 z28 305) and its been fine everyday untill today. i tried to start it but it would turn over but not fire up normally. it did fire up once but it had a very waek idle only if held it at 2500 rpm. i checked the carb and it had lots of gas coming out the top...mostly from a little hole in the top front. i did notice a clicking sound and it stopped when i unplugged the front left connector. im going to take it apart tomorrow but wanted some ideas to what may be going on.
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Old 07-11-2011, 02:49 AM
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Re: CC rochester fuel leaking from the top

stuck float
Old 07-11-2011, 10:28 AM
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Re: CC rochester fuel leaking from the top

thanks a lot. im new to these computer carbs. never heard a carb click before.
Old 07-11-2011, 03:18 PM
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Re: CC rochester fuel leaking from the top

Originally Posted by ROCITUP
thanks a lot. im new to these computer carbs. never heard a carb click before.
The clicking you hear is the Mixture Control Solonoid (MCS) energizing. It will click for about 10 seconds when you turn the ignition to "on". Since these carbs are the step before fuel injection, it's used for part throttle fuel metering.
Old 07-11-2011, 09:25 PM
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Re: CC rochester fuel leaking from the top

here is an update. i took it apart and found the float way too low when pressing the needle down. so i adjusted it and i put all back together. kinda tricky at first but now its very cool. thanks guys i owe you a brewski.

Last edited by ROCITUP; 07-11-2011 at 09:28 PM.
Old 07-12-2011, 10:37 AM
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Re: CC rochester fuel leaking from the top

not outta the woods yet. this morning it was unde powered and it took a minute of very slow driving for the power to come. im convinced its a sticky needle. any input? thanks.
Old 07-12-2011, 12:32 PM
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Re: CC rochester fuel leaking from the top

after researching even further i saw i have the needle clipped wrong.
Old 07-12-2011, 03:12 PM
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Re: CC rochester fuel leaking from the top

There's a great sticky thread on here somewhere with tons of huge pictures detailing a complete rebuild of these carbs, along with another thread featuring scans from the shop manual of how to adjust things. Best bet is to get a rebuild kit, find those threads, and get to work. I'm sure at the very least (if you dont want to do a full rebuild now) you'll find info/pics of how the needle and float go (along with specs of how high it should be set), I remember there being something weird about it but it's been a couple years.

Your post from 1137 today is most likely related to the settings for your choke and all the linkages related to it. Theres base settings you should find and adjust from, but basically you want the choke open the right amount for the right amount of time to compensate for how a cold engine needs more fuel. There's also a lockout that keeps your secondaries from opening until the choke is warmed up enough.
Old 07-12-2011, 04:44 PM
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Re: CC rochester fuel leaking from the top

There is supposed to be a plug in that hole. other wise dirt is getting inside and messing things up. I'm in the middle of doing a full rebuild on my E4ME. If you plan to keep this car for a while invest in the right tools adjusting these carbs without them sucks.
Old 07-14-2011, 11:12 PM
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Re: CC rochester fuel leaking from the top

so my ride revs fine in the driveway but it has a horrible flat spot when i try to accelerate. my float is adjusted at 3/16 of an inch from the top of the casting. but my solenoid lean adjust screw is backed out two turns. is that too much? that with the float that is the only thing i can think of that is off. i n reverse up my driveway it also has NO hesitation.any sugestions fellas. im thinking of ditching this stuff and just converting the whole car without smog, computer, and just go with old world conventional induction.....which would be way easier.
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