Starting Issues '81
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Joined: Sep 2023
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From: Howard County
Starting Issues '81
Hello...I have an 81. Pretty much everything is stock. It runs great however it it sits for more than a couple of days I need to use carb starter to get it started. Any first blush ideas? Thank you.
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Joined: Jul 2005
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From: WI
Probably fuel related. Couple things come to mind:
1) Fuel is draining out of the carb for some reason. The "well plugs" in the main body (if your car has them), could be allowing the float bowl to drain when sitting. Common problem on a Q-jet and back in the day.
2) The correct fuel filter I believe should have a one-way check valve inside it. Maybe yours doesn't have one or it's faulty
3) Fuel pump flow/pressure could be low. You can unhook, add a length of hose, have someone hit the starter and watch how much flows into a bucket. If the car runs ok once you get it started, it's probably not the fuel filter.
Probably the easiest & cheapest way to start is with a new Stock-style fuel filter. A quality one which has a check valve in it. Like from NAPA. I'd start there first.
.
1) Fuel is draining out of the carb for some reason. The "well plugs" in the main body (if your car has them), could be allowing the float bowl to drain when sitting. Common problem on a Q-jet and back in the day.
2) The correct fuel filter I believe should have a one-way check valve inside it. Maybe yours doesn't have one or it's faulty
3) Fuel pump flow/pressure could be low. You can unhook, add a length of hose, have someone hit the starter and watch how much flows into a bucket. If the car runs ok once you get it started, it's probably not the fuel filter.
Probably the easiest & cheapest way to start is with a new Stock-style fuel filter. A quality one which has a check valve in it. Like from NAPA. I'd start there first.
.
Last edited by Mark G; Sep 27, 2023 at 08:47 PM.
Instructor
Joined: Sep 2013
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From: Palmyra NY
Your losing fuel from the bottom of your carb through the well plugs. My car does the same thing. All I do is put a little gas in a jar and pour it down the primary side. Get inside, pump it once and it'll start. You'll have to use some judgement on cool and hot days. You can either give it too little or too much gas from your jar resulting in starting differences.
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Or, since it's a carburetorated car. Pump the throttle 3 times. Crank for 15 -20 seconds, let off the starter. Pump the throttle 3 more times, hold the throttle down just a fuzz. Crank again. Should light the second time after 5 - 10 seconds.
it's not a modern car. Please don't expect it to be one.
it's not a modern car. Please don't expect it to be one.
Dr. Detroit
Joined: Mar 2012
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From: New Braunfels Texas
Well plugs are actually very rare......and kind of an urban legend of Q-Jets......I personally have never seen it......some people that think that is where the carb is leaking automatically blame the well plugs.
In my experience.....carb drainback is caused by two things......no check valve in the fuel filter or the "windowed" needle/seat assembly......the old style seat was a full cup and the fuel level could ride higher in the bowl without and drainback regardless or the conditions.....
Stick a check valve filter in it and see if it changes.......
Jebby
In my experience.....carb drainback is caused by two things......no check valve in the fuel filter or the "windowed" needle/seat assembly......the old style seat was a full cup and the fuel level could ride higher in the bowl without and drainback regardless or the conditions.....
Stick a check valve filter in it and see if it changes.......
Jebby
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Yeah... We need to have the Forum force folks to post pictures with new question threads.
The correct check-valve filter, and proper timing, halved the time it takes to start my 79 from cold. So I'll suggest following @lars timing instructions, and ask him for advice finding a rebuildable Q-Jet.
The correct check-valve filter, and proper timing, halved the time it takes to start my 79 from cold. So I'll suggest following @lars timing instructions, and ask him for advice finding a rebuildable Q-Jet.
Instructor
Joined: Sep 2013
Posts: 175
Likes: 3
From: Palmyra NY
Well plugs are actually very rare......and kind of an urban legend of Q-Jets......I personally have never seen it......some people that think that is where the carb is leaking automatically blame the well plugs.
In my experience.....carb drainback is caused by two things......no check valve in the fuel filter or the "windowed" needle/seat assembly......the old style seat was a full cup and the fuel level could ride higher in the bowl without and drainback regardless or the conditions.....
Stick a check valve filter in it and see if it changes.......
Jebby
In my experience.....carb drainback is caused by two things......no check valve in the fuel filter or the "windowed" needle/seat assembly......the old style seat was a full cup and the fuel level could ride higher in the bowl without and drainback regardless or the conditions.....
Stick a check valve filter in it and see if it changes.......
Jebby
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Joined: Oct 2012
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From: Dunedin NZ.
Before you do that, take the top off the air cleaner when the car has been sitting overnight. Manually work the throttle and see if any gas squirts from the accelerator nozzles, (you may need to push the choke flap out of the way to see this). If no gas is seen, turn the motor over on the starter for about 10 seconds without touching the accelerator so the choke doesn't set and then try the same check, if you can now see gas squirting, pump the gas a few times and then try to start the motor. I have an Edelbrock 1906 AVS2 and have to do this when the car has been sitting overnight, it seems the well for the accelerator pump dries out and there is no gas to prime the engine to allow it to start. I expect an insulation spacer under the carb would fix the issue but no room for that (at least on my car)
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Joined: Sep 2023
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From: Howard County
So strange. I took the hose out of the carb and cranked it and no fuel came from before and after the filter while cranking. I poured gas down the carb and it eventually started and stayed started. Do you think the problem is the sending unit, fuel relay and fuel pump?