Car starts great then dies 30 secs later - ????
11-01-2016, 03:20 PM
#1
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Join Date: Aug 2014
Location: Tyler/Tx/South/USA
Posts: 51
Car starts great then dies 30 secs later - ????
I have a 260 V8 with 2100 2 barrel. The carb has had a kit recently.
All adjustments are set and float is working properly and wet tested.
It starts great, choke works as it should and so does the fast idle. So why after 30 seconds does it start to miss and sputter and gradually die after another 10 seconds? I've stood over it for the 30 seconds and tried working the choke manually to make it more lean and that doesn't help.
Seems like a fuel related problem to me. One other thing, if I restart it again and again and finally get the engine warm then things improve a lot.
All help is much appreciated. Thanks!
All adjustments are set and float is working properly and wet tested.
It starts great, choke works as it should and so does the fast idle. So why after 30 seconds does it start to miss and sputter and gradually die after another 10 seconds? I've stood over it for the 30 seconds and tried working the choke manually to make it more lean and that doesn't help.
Seems like a fuel related problem to me. One other thing, if I restart it again and again and finally get the engine warm then things improve a lot.
All help is much appreciated. Thanks!
11-01-2016, 04:39 PM
#3
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Join Date: Aug 2014
Location: Tyler/Tx/South/USA
Posts: 51
I wonder if it's going into fuel shortage after 30 seconds. But, I know the float is working because I can remove the top of the carb and I get a good measurement, wet. Also, there's pressure on the fuel line - if I push the float down fuel squirts out.
When finally warm the engine runs very smooth. The problem can start at a stoplight, but just sometimes.
11-01-2016, 07:00 PM
#4
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Location: Hills of California
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checking for vac leaks might be a good next step...With the engine running spray some carb cleaner around the carb base and intake and intake and heads...also if you are running vac assisted brakes plug the line momentarily and see if it smooths out.
If the carb cleaner causes engine rpm to drop then that would be a source of the leak
If the carb cleaner causes engine rpm to drop then that would be a source of the leak
11-03-2016, 10:38 AM
#6
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Blow out all passages
It surprises me that it starts and runs so well, then instantly dies or starts the coughing and sputtering with no warning.
I will get some carb cleaner later today and try checking for vacuum leaks. Frustrating!
11-03-2016, 10:57 AM
#7
Join Date: Feb 2016
Location: Mississippi
Posts: 14
I ran into an issue after I put my new motor in my 65. It would run great for a few minutes and then cut off sometimes. Then other times it would run great for two weeks maybe then cut off again. A friend told me to take the fuel line off at the carb. and also at the fuel tank. Put your air hose on one end and see if it is stopped up or partially stopped up. I did that and all kinds of junk came out of the line. I had to end up replacing the fuel tank because of the rust in the bottom was getting in my fuel line and stopping it up.
11-03-2016, 12:56 PM
#8
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Join Date: Aug 2014
Location: Tyler/Tx/South/USA
Posts: 51
Fuel line
I ran into an issue after I put my new motor in my 65. It would run great for a few minutes and then cut off sometimes. Then other times it would run great for two weeks maybe then cut off again. A friend told me to take the fuel line off at the carb. and also at the fuel tank. Put your air hose on one end and see if it is stopped up or partially stopped up. I did that and all kinds of junk came out of the line. I had to end up replacing the fuel tank because of the rust in the bottom was getting in my fuel line and stopping it up.
I notice that a fair amount of moisture is coming out of the exhaust pipes. It smells like water, no gasoline odor. I have the idle mixture screws set to 1 1/2 turns out from lightly seated. Could it be too rich? I recall trying to turn both screws in about 1/4 of a turn and I believe anything more and the idle gets rough.
11-03-2016, 01:12 PM
#9
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Location: Hills of California
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if it runs great for 30 sec then dies its not a carb issue.
still check for vac leaks but that seems inconsistent with the runs great part now as well.
fuel delivery is most suspect at this point....Ignition is second. Start with fuel delivery.
So fire it up and run until it dies. once it dies do not attempt to restart it. Take off the air cleaner and look down the primary throttle barrels on the carb. Apply full throttle while looking down the carb. You should see a good solid stream of fuel from the accelerator pump as you apply full throttle. Try this 3x in a row. If you get one good stream of fuel on the first try and little to nothing on the next attempts or nothing on any attempts this indicates that carb has run out of fuel and there is no fuel available to run the accelerator pump let alone the engine.
still check for vac leaks but that seems inconsistent with the runs great part now as well.
fuel delivery is most suspect at this point....Ignition is second. Start with fuel delivery.
So fire it up and run until it dies. once it dies do not attempt to restart it. Take off the air cleaner and look down the primary throttle barrels on the carb. Apply full throttle while looking down the carb. You should see a good solid stream of fuel from the accelerator pump as you apply full throttle. Try this 3x in a row. If you get one good stream of fuel on the first try and little to nothing on the next attempts or nothing on any attempts this indicates that carb has run out of fuel and there is no fuel available to run the accelerator pump let alone the engine.
11-04-2016, 07:53 AM
#10
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Join Date: Aug 2014
Location: Tyler/Tx/South/USA
Posts: 51
if it runs great for 30 sec then dies its not a carb issue.
still check for vac leaks but that seems inconsistent with the runs great part now as well.
fuel delivery is most suspect at this point....Ignition is second. Start with fuel delivery.
So fire it up and run until it dies. once it dies do not attempt to restart it. Take off the air cleaner and look down the primary throttle barrels on the carb. Apply full throttle while looking down the carb. You should see a good solid stream of fuel from the accelerator pump as you apply full throttle. Try this 3x in a row. If you get one good stream of fuel on the first try and little to nothing on the next attempts or nothing on any attempts this indicates that carb has run out of fuel and there is no fuel available to run the accelerator pump let alone the engine.
still check for vac leaks but that seems inconsistent with the runs great part now as well.
fuel delivery is most suspect at this point....Ignition is second. Start with fuel delivery.
So fire it up and run until it dies. once it dies do not attempt to restart it. Take off the air cleaner and look down the primary throttle barrels on the carb. Apply full throttle while looking down the carb. You should see a good solid stream of fuel from the accelerator pump as you apply full throttle. Try this 3x in a row. If you get one good stream of fuel on the first try and little to nothing on the next attempts or nothing on any attempts this indicates that carb has run out of fuel and there is no fuel available to run the accelerator pump let alone the engine.
Thanks, I will try that. I'm also going to take some steps to make sure I don't have water in the gas tank. Not sure how it would run just fine for awhile if there was water present, then not run, but will make sure anyway.
