02-11-2017, 08:28 PM | #1 |
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Q-jet issues!
Having trouble firing up my truck.
I'm getting: Air Fuel to the carb And spark I can pour a little gas or spray starter fluid into the carb and it'll fire and run for a few seconds. I just can't get it running. I have changed the fuel filter and got same results. Any help is appreciated!! Thanks guys! Posted via Mobile Device |
02-11-2017, 09:03 PM | #2 |
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Re: Q-jet issues!
Look in the carb, with the truck not running, operate the throttle. Squirting fuel? Could be the float is stuck shut and not allowing gas into the carb.
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02-11-2017, 11:29 PM | #3 |
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Re: Q-jet issues!
That's my problem. I don't know what's what in carbs. Do you mean look down with the filter off? Is unsticking a float difficult to to? Or can you describe what you mean?
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02-11-2017, 11:32 PM | #4 |
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Re: Q-jet issues!
Look in down past the choke plate. Use a flashlight. Watch for a good shot of fuel as you stroke the throttle.
Which filter did you change? |
02-11-2017, 11:38 PM | #5 |
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02-11-2017, 11:40 PM | #6 |
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Re: Q-jet issues!
I replaced the paper filter at the front of the carb. It's the file suppl line from the pump to the carb.
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02-11-2017, 11:41 PM | #7 |
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Re: Q-jet issues!
Typo... It's on the end of the supply line from the pump to the carb.
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02-11-2017, 11:54 PM | #8 |
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Re: Q-jet issues!
Are you meaning the one in the carb?
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02-11-2017, 11:57 PM | #9 |
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Re: Q-jet issues!
Yes the filter goes into the base of the carb in the front
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02-12-2017, 12:02 AM | #10 |
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Re: Q-jet issues!
Checked throttle. Definitely no fuel coming out
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02-12-2017, 12:04 AM | #11 |
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Re: Q-jet issues!
You might have the filter in wrong.
If no fuel, pull the new filter out for a test, put it back togethor and crank it over and see if it starts or has fuel inside the carb. Do you have a working choke? |
02-12-2017, 12:08 AM | #12 |
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Re: Q-jet issues!
Do I take the filter out and reconnect the line and turn the engine over checking for fuel?
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02-12-2017, 12:12 AM | #13 |
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Re: Q-jet issues!
Yup!!
JUst a test! And do you have a working choke? |
02-12-2017, 12:15 AM | #14 |
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Re: Q-jet issues!
Took filter out. Reconnected the lines. Manually checked throttle and turned engine. No fuel is getting to carb.
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02-12-2017, 12:16 AM | #15 |
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Re: Q-jet issues!
Not sure on choke. I don't think so because previous owner has a sprin holding plates open. I believe that is the choke. Again sorry if that is confusing I just don't know my way around carbs.
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02-12-2017, 12:22 AM | #16 |
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Re: Q-jet issues!
Take a pic.
Air cleaner off. Easier to diagnose that way. Top, sides front of carb. Hang in, we'll have you designing carbs soon!! |
02-12-2017, 12:34 AM | #17 |
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Re: Q-jet issues!
How do I upload a picture onto the forum?
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02-12-2017, 01:06 AM | #18 |
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Re: Q-jet issues!
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02-12-2017, 02:02 AM | #19 |
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Re: Q-jet issues!
I can't get pictures up for some reason. I have dug around on the internet and I think you're on point with the float. What is the process for getting the float/needle working again? I also realize I'll need to take at least the top off and clean it out.
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02-12-2017, 07:06 AM | #20 |
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Re: Q-jet issues!
OK, back up. I know my way around carburetors, but geezer#99 has forgotten more than I'll ever know.
Couple of assumptions I was running on, first that it was running before you did any work. Second, that you had more knowledge than you do. (nothing against you, I mean I know squat about fuel injection ) He asked about the fuel filter. Some inline filters, if backwards, can stop fuel flow. Was the filter changed because it didn't run? Are we sure the fuel pump is good? Figure out how to post the pics he requested, wouldn't hurt to browse the engine/drivetrain section, there are a couple recent threads on q-jets (quadrajet carburetors) that may enlighten you, or at least give you a more working knowledge. Help us to help you.
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02-12-2017, 08:30 AM | #21 |
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Re: Q-jet issues!
Yes truck was running before problem. I changed the filter first hoping that would solve the problem. I then disconnected the fuel supply line from the pump to the carb got the wife to turn the engine and fuel shot out. So I assumed the lines were clear and the pump was good the problem is somewhere in the carb. And like I said in my original post I can pour a small amount of fuel in the carb and it'll fire up for a few seconds. So fuel is not getting in somehow. The stuck needle/float theory seems realistic. I just need to know how to check or fix that
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02-12-2017, 09:53 AM | #22 |
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Re: Q-jet issues!
Did you install the spring first then the filter? It goes plastic gasket, spring, filter with hole facing the fuel line.
Sounds like a stuck float to me, either that or the clip that pulls the needle out of the jet (inlet) broke and the needle is sitting in the jet. You can try tapping the carb with a rubber mallet or the like (be gentle, that pot metal is pretty weak) and see if you can get fuel to move. If the float is stuck up, which it would have to be to shut off fuel flow, that should knock it free, and you should see fuel while hitting the accelerator after cranking a bit, since you know fuel is ATTEMPTING to flow through.
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02-12-2017, 10:17 AM | #23 | |
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Re: Q-jet issues!
Quote:
Pull the fuel line off the carb, put the end in a clear quart jar and have the wife (aka the boss) crank it over and over for you. If the fuel pump is good it should fill the jar in 30 seconds. If it spits and sputters with no strong spurts then it might be fuel pump time. But If that turns out good, then we'll dig deeper into the carb. One step at a time grasshopper!! LOL!! Sometimes when you try to upload pics you have to resize them. Make them smaller. Last edited by geezer#99; 02-12-2017 at 10:26 AM. |
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02-12-2017, 08:45 PM | #24 |
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Re: Q-jet issues!
Got it running boys! The needle was the problem I believe. Took carb out and removed the top half. Pulled the needle , float and the brass bowl out. Cleans them up and put some 3 in 1 oil on the parts. Also put some marvel in the gas hoping that will clean up some old funk in there. Thanks to everyone who chimed in on the thread. Couldn't have done it without the help!!!! #geezer99 #donut
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02-13-2017, 04:57 AM | #25 |
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Re: Q-jet issues!
Just glad you got it. Thanks for the update.
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