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Discussion Starter #1
What would cause a carb (QJet) to spew gas out of the vent tube (looks like it's from there) when I hit the gas after it warms up. I have a small spacer, about 1/4", do I need a bigger spacer or could it be something else. I thought the carb top was leaking at the plunger but I think it may be when it warms up and I rev the gas.
 

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The inlet needle and seat is open...........

Several causes: In order of likeliness

1. Heavy float...

2. Dirt in the needle and seat....

3. Way to much fuel pressure
 

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Has this motor set for a long time? If so, the fuel will dry up in the float bowl and coat everything with a brown film and hang up the float. You'll need to separate the top half of the carb from the bottom. Be careful with the gasket and hopefully you can reuse it. Look for the brown varnish film and remove the needle and seat for inspection. If it' s in very bad shape it probably should be completely dissasembled, cleaned and overhauled.
 

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Discussion Starter #5
I bought the carb a few months ago and the guy said it was running. It sat empty until I just tried it. Would spraying carb cleaner help clean it out or do I need to tak it apart?
 

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Discussion Starter #7
removed the top, very little specks of sediment in bottom, brown film on bottom of bowl, cleaned it up with carb cleaner; anything else I should do. the carb looks clean inside & out. What should I do to check the float?
 

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To check the float, it should be very light in weight. You can float it in a pan of gas; sinks, no good.

Check needle & seat for trash. Assemble float to carb top with needle & seat and turn upside down; blow into gas inlet and should not be any air pass through.
 

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Discussion Starter #9
Why would a float be heavy, has a leak? Are you saying to re-assemble the carb and then blow into inlet and no air should come out of where, what does it mean if there is?
 

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Why would a float be heavy, has a leak? Are you saying to re-assemble the carb and then blow into inlet and no air should come out of where, what does it mean if there is?
turn carb upside down that will hang the float in the up postion same as if there was gas in bowl.blow light air into fuel inlet you should not hear air going into bowl.if you do the needle assembly is not seating and that is why your flooding.flip carb right side up and blow again you should hear air going into bowl
 

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Discussion Starter #12
I blew into carb with it upside down and couldn't get any air into it, same thing when I turned it right side up and blew into it; nothing. Your talking about blowing with your mouth and not compressor right.
This carb was fine when I initially started the car and ran it for about ten minutes, stopped it because of intake & valve cover leaks. When I re-started it again, didn't start so great, ran like crap then gas started shooting out, leaking by plunger. I have an inle filter along with the filter in the carb (which looks new), so I'm assuming the carb may have had some dirt in it already. Cleaned it out and will try again.
 

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I blew into carb with it upside down and couldn't get any air into it, same thing when I turned it right side up and blew into it; nothing. Your talking about blowing with your mouth and not compressor right.
This carb was fine when I initially started the car and ran it for about ten minutes, stopped it because of intake & valve cover leaks. When I re-started it again, didn't start so great, ran like crap then gas started shooting out, leaking by plunger. I have an inle filter along with the filter in the carb (which looks new), so I'm assuming the carb may have had some dirt in it already. Cleaned it out and will try again.
yea blow with mouth.sound like needle assy. is plugged.got somthing under needle thats not leting fuel into the bowl
 

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Discussion Starter #14
Started it up today and the carb seems fine, ran it for about 10 minutes, no problems except for this dam valve cover. Two gaskets later and leaking like a sieve. Should there be smoke blowing out of breather, also have smoke blowing out of hose that is connected to rear of block which will be hooked to air cleaner. The smoke is light but visible. It's running out of valve cover and seeping into header and blowing out exhaust, neighbors must love me now. Sending it back to Summit for a new one, ugggh! Thanks for all your help with the carb.
 

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smoke is blow by.its normal to have a little but alot indicates tired rings.if your not getting a lot of smoke out tail pipe your ok its just blow by.
 

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Discussion Starter #16
I have a feeling (hoping) it has something to do with the oil leaking from the valve cover down into the header gasket because all the smoke was from the drivers side exhaust which is same side as leak. There was a lot of smoke at startup and then subsided as the car warmed up. I probably need to adjust the carb as well as it's a used qjet, it may be running rich. Thanks for all your advice.
 
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