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Old 01-26-2003, 01:55 PM
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Post Q-Jet Carb Problems...engine dies.

Someone please tell me whats wrong with this carb. Warm or cold. After I drive for around 15 min. the idle drops really low until it finally dies. While driving its OK. Just sudden drop in RPM during idle. Not getting the gas it needs. Also, the idle varies, for the first 15min or so. Most really high, sometimes normal. Just never the same. Carb was overhauled. Nothing sticking or dirty. Carb did same before overhaul. Sound familiar to anyone?

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Old 01-26-2003, 02:32 PM
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sounds like fuel pump maybe pulling air inline between tank and pump. look at venttube almost in center of carb if pulling air vapor will normanly show their? something to look at. good luck.
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Old 01-26-2003, 02:53 PM
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I noticed that the clear fuel filter filled full of gas with my other carb on, and only 1/3 full to finally becoming almost empty, with this carb. Pump and lines are unchanged and fine. What on this carb(same model as other carb) is causing this?
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Old 01-27-2003, 05:15 PM
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I'm having a similar problem with my 350 small block. At speed it runs like a dream but it doesn't want to idle right. The rpm's keep going up and down and occasionally it stalls. On restart it sounds like it is fuel starved and is very hard to start and occassionaly backfires through the carby. I noticed that the clear fuel filter is not always full. So maybe I have a similar problem. Anyone with any ideas.
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Old 01-27-2003, 08:43 PM
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when you over hauled your carb, did you replace the small fuel filter in the carb, it's right where the fuel line conect to the carb.
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Old 01-28-2003, 11:17 AM
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Also check the throttle arm shaft, if it's loose you could be sucking air around the shaft which will show up at idle speeds. The reason that it's less noticeable when cold is that it runs richer when the choke is on.
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Old 01-31-2003, 10:43 AM
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[quote]Originally posted by MopaRV:
<strong>Someone please tell me whats wrong with this carb. Warm or cold. After I drive for around 15 min. the idle drops really low until it finally dies. While driving its OK. Just sudden drop in RPM during idle. Not getting the gas it needs. Also, the idle varies, for the first 15min or so. Most really high, sometimes normal. Just never the same. Carb was overhauled. Nothing sticking or dirty. Carb did same before overhaul. Sound familiar to anyone?</strong><hr></blockquote>
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Old 01-31-2003, 10:52 AM
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how old is the car thatit is in ? you might check the fuel lines to see if they show any rust.chek the fuel hose used to connect the fuel lines, and make sure they are in good shape. had the same prob in my truck when i first got it had a hole in the fuel line right under the cab the size of a dime
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Old 01-31-2003, 11:00 AM
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[quote]Originally posted by MopaRV:
<strong>Someone please tell me whats wrong with this carb. Warm or cold. After I drive for around 15 min. the idle drops really low until it finally dies. While driving its OK. Just sudden drop in RPM during idle. Not getting the gas it needs. Also, the idle varies, for the first 15min or so. Most really high, sometimes normal. Just never the same. Carb was overhauled. Nothing sticking or dirty. Carb did same before overhaul. Sound familiar to anyone?</strong><hr></blockquote>


<img src="graemlins/crash.gif" border="0" alt="[crash]" />
Hey MoparV!
Yup, sounds real familiar! Turn the Q-jet over and check the two plug-lQQking things in the center of the baseplate/carb body. These are some sort of passageways that are capped from the factory. Eventually, a good number of Q-jets start leaking here and you end up with the exact symptoms you describe. The only fix I'm familiar with is to epoxy all around these caps to stop the leaking into the manifold. Come to think of it, I do seem to remember reading about someone making this type of repair kit, I just can't remember who. I think if you check your exhaust right as it's shutting off, you might notice some black smoke coming out the pipes. This will indicate a too-rich condition going on when the engine shuts off, not too lean. You might not be able to fix it, so a new carb might be in the works! Check it out and post your observations! Good luck! BD58
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