Fb doesn't hold idle without choke?
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Fb doesn't hold idle without choke?
Hello! 83 GSL 12A.
before i say anything, the car has had the carb rebuilt recently.
The car doesn't hold idle at all unless the choke is being used and if i let it go, it just dies? why is that.?
before i say anything, the car has had the carb rebuilt recently.
The car doesn't hold idle at all unless the choke is being used and if i let it go, it just dies? why is that.?
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I can't find a vacuum leak? Where could it be?
I checked all hoses and they look fine..
no i haven't done a compression test :/
#4
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I would first do a compression test. You can use a piston compression tester with the valve held down. Not the most accurate but it will tell you if there is a major issue with compression.
If you can keep it running with the choke in and your foot on the gas to keep the R's up, this could point towards of bad compression because the choke is off. You want to keep the R's as low as possible and still keep it running.
If you can keep it running with the choke in and your foot on the gas to keep the R's up, this could point towards of bad compression because the choke is off. You want to keep the R's as low as possible and still keep it running.
#5
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Easier than using a compression tester, you can just remove all the spark plugs, disable the ignition to prevent any accidental combustion, and crank it. If all the wooshes sound consistent with each other and decently powerful, you should be just fine on compression. Probably just do one rotor's plugs at a time, so you can better tell the wooshes apart.
Running only on choke is a classic symptom of a vacuum leak. Vacuum leak means more air than there needs to be, and using choke is balancing the excess air with more fuel, generally.
Running only on choke is a classic symptom of a vacuum leak. Vacuum leak means more air than there needs to be, and using choke is balancing the excess air with more fuel, generally.
Last edited by Ta-Aikah; 02-22-21 at 10:27 AM.
#6
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Anywhere that sees vacuum at idle . Is the car still stock as far as smog equipment goes? When you rebuilt the carb did you touch anything else? How have you been checking for leaks?
First thing I would do is as KCrepu suggested and see if it will run with your foot on the gas but no choke - the choke **** (in addition to closing the choke) also opens the throttle a little bit. If it runs without the choke and your foot on the pedal that's a good start. Also from the short clip the engine sounds fairly healthy (or at least smooth), but a compression test is the only way to put a metric on that.
A couple pictures of the carb/top of the engine might prove useful as well - perhaps someone will spot a missing something-or-other.
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That's good. Don't bother tracking one down to replace it - doing so more often that not will cause more problems than you started with.
Anywhere that sees vacuum at idle . Is the car still stock as far as smog equipment goes? When you rebuilt the carb did you touch anything else? How have you been checking for leaks?
First thing I would do is as KCrepu suggested and see if it will run with your foot on the gas but no choke - the choke **** (in addition to closing the choke) also opens the throttle a little bit. If it runs without the choke and your foot on the pedal that's a good start. Also from the short clip the engine sounds fairly healthy (or at least smooth), but a compression test is the only way to put a metric on that.
A couple pictures of the carb/top of the engine might prove useful as well - perhaps someone will spot a missing something-or-other.
Anywhere that sees vacuum at idle . Is the car still stock as far as smog equipment goes? When you rebuilt the carb did you touch anything else? How have you been checking for leaks?
First thing I would do is as KCrepu suggested and see if it will run with your foot on the gas but no choke - the choke **** (in addition to closing the choke) also opens the throttle a little bit. If it runs without the choke and your foot on the pedal that's a good start. Also from the short clip the engine sounds fairly healthy (or at least smooth), but a compression test is the only way to put a metric on that.
A couple pictures of the carb/top of the engine might prove useful as well - perhaps someone will spot a missing something-or-other.
Everything looks stock so far from the vacuum lines area..
I just checked the vacuum hoses and they all look super new like the previous owner did some work to this car.
I tried to put everything back in its place as far as the carb rebuild.
So now I have another issue where the car doesn't start anymore after that day it died.
But someone came and checked out the car and said that it doesn't start because it's not getting gas and someone online suggested that it could be because the tank is rusted and little particles are going in.
I see little black stuff in the carb again like little dots and they said it was rust.
They recommended me changing the fuel pump and flush fuel tank. What do you think?
Here are some photos.
Easier than using a compression tester, you can just remove all the spark plugs, disable the ignition to prevent any accidental combustion, and crank it. If all the wooshes sound consistent with each other and decently powerful, you should be just fine on compression. Probably just do one rotor's plugs at a time, so you can better tell the wooshes apart.
Running only on choke is a classic symptom of a vacuum leak. Vacuum leak means more air than there needs to be, and using choke is balancing the excess air with more fuel, generally.
Running only on choke is a classic symptom of a vacuum leak. Vacuum leak means more air than there needs to be, and using choke is balancing the excess air with more fuel, generally.
Now the car doesn't start. As I stated above, my friend said it's not getting gas and there are little particles in the carb again (black little dots) and he said it was rust from the tank.
he said I should change the fuel pump and clean the tank and try again but that should be my start issue because it's not getting gas.
I would first do a compression test. You can use a piston compression tester with the valve held down. Not the most accurate but it will tell you if there is a major issue with compression.
If you can keep it running with the choke in and your foot on the gas to keep the R's up, this could point towards of bad compression because the choke is off. You want to keep the R's as low as possible and still keep it running.
If you can keep it running with the choke in and your foot on the gas to keep the R's up, this could point towards of bad compression because the choke is off. You want to keep the R's as low as possible and still keep it running.
Yeah it just dies. you don't think it could be because of the carb adjustment?
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#9
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You can check the fuel pump working by removing the feed to the carb and putting it in some sort of container. Turn ignition on and see if fuel pours into the container, (If the pump is wired to be always on with ignition) plus you should be able to see if there are any particles in the gas that would be making their way to the carb.
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As for the fuel pump replacing I can't even remove the pump cus the bolts are so rusted lol. now sure what to do.
You can check the fuel pump working by removing the feed to the carb and putting it in some sort of container. Turn ignition on and see if fuel pours into the container, (If the pump is wired to be always on with ignition) plus you should be able to see if there are any particles in the gas that would be making their way to the carb.
By feed you mean the hoses that goes to the carb? there are 2 correct?
#11
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Check to ensure you have voltage at the fuel pump. Remove the drivers side bin to access the wiring. If no power, check the fuel pump relay. It's under the dash newq the drivers right leg. It can be jumpered if it failed.
If you haven't got the Factory Service Manual yet get it here: Foxed.ca
If you haven't got the Factory Service Manual yet get it here: Foxed.ca
#12
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Check to ensure you have voltage at the fuel pump. Remove the drivers side bin to access the wiring. If no power, check the fuel pump relay. It's under the dash newq the drivers right leg. It can be jumpered if it failed.
If you haven't got the Factory Service Manual yet get it here: Foxed.ca
If you haven't got the Factory Service Manual yet get it here: Foxed.ca
So if there is no voltage to the fuel pump it could mean the relay is bad?
So idk if this has to do with anything but when I turn on the car to "ON" position, I can hear the pump running? does that mean it's working?
#13
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Also worth noting that just because lines are "new" doesn't mean they're not leaking. I've had some cheapo silicone tubes that don't perfectly seal and ended up leaking until i put a hose clamp on them (for the bigger ~12mm lines, not the 6mm lines).
I still think you need to start simple and look for vacuum leaks. Get a can of starter fluid and start spraying anywhere while listening for rev's to increase. I may be crazy, but is there a line here? This is where the idle compensation tube runs I think.
I still think you need to start simple and look for vacuum leaks. Get a can of starter fluid and start spraying anywhere while listening for rev's to increase. I may be crazy, but is there a line here? This is where the idle compensation tube runs I think.
#15
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The feed is the bigger of the two lines going to the carb. You should be able to tell by the size of the steel line if not the rubber hose.
I also believe the RETURN line is the line with what looks like the factory check valve in it.
I also believe the RETURN line is the line with what looks like the factory check valve in it.
#16
3D Printed
Perhaps the issue has been resolved by now, but I'd just try and get it to catch/run on ether, then start digging into the fuel system. If it does catch you know the ignition system is at least functional, then of course proceed to the fuel system issues.
From the black specs you're noticing in the carb it does sound like there's debris in the fuel system. Go through what the others have already said first, but if there's still issues with it running or not running for very long and then stalling you'll probably want to at least partially disassemble the carb again. There is a filter screen under each fuel inlet banjo bolt, and there may also be debris in the float bowls (and probably elsewhere).
Now let's say you've determined that there's debris in the fuel system:
Dropping the tank isn't too hard, just keep track of which fuel lines go where. I use blue painters tape and draw a different shape on each. I'd suggest syphoning out whatever fuel you can to make the job easier. Or actually, does the 83 have a drain plug? I don't remember, but if it does use that to drain the tank. If you get the tank out and it's all rusty either you can try cleaning and coating it (there's plenty of info online) or you can bring it to a radiator shop and they can likely do it for you. Replace the fuel filter and clean out the carb again. Before you hook everything back up run the pump with the feed line at the carb going into a container of some sort. This will hopefully flush out whatever debris is still in the line. After that hook it all up and hope it fires.
That all said, I'd still try ether first. If that doesn't work then do ^^^.
From the black specs you're noticing in the carb it does sound like there's debris in the fuel system. Go through what the others have already said first, but if there's still issues with it running or not running for very long and then stalling you'll probably want to at least partially disassemble the carb again. There is a filter screen under each fuel inlet banjo bolt, and there may also be debris in the float bowls (and probably elsewhere).
Now let's say you've determined that there's debris in the fuel system:
Dropping the tank isn't too hard, just keep track of which fuel lines go where. I use blue painters tape and draw a different shape on each. I'd suggest syphoning out whatever fuel you can to make the job easier. Or actually, does the 83 have a drain plug? I don't remember, but if it does use that to drain the tank. If you get the tank out and it's all rusty either you can try cleaning and coating it (there's plenty of info online) or you can bring it to a radiator shop and they can likely do it for you. Replace the fuel filter and clean out the carb again. Before you hook everything back up run the pump with the feed line at the carb going into a container of some sort. This will hopefully flush out whatever debris is still in the line. After that hook it all up and hope it fires.
That all said, I'd still try ether first. If that doesn't work then do ^^^.
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