Chevy Tri Five Forum banner
Cancel
Create thread New Garage Forums

Diagnose the problem...fuel?

Jump to Latest
1 - 20 of 29 Posts

jchochole

· Registered
Joined
·
109 Posts
Discussion starter · #1 · (Edited)
Okay, I finally got my '57 Bel-air with straight 6 back together and tried to start her....pumped the pedal 15-20 times, tried it and nothing...pumped more....nothing. Stuck my finger in the carb -bone dry....primed the carb with gas and she popped a few times and sputtered 'til dead. Pumped the pedal a few more and tried it again...nothing...little more gas into the carb and she ran rough for 10 seconds...then died.

Whaddya think? My fuel pump worked before I took my carb apart- could it have crapped out? Or could it be somrthing else?

Figuring it all out,
Jim from Oswego
 
#2 ·
Could be a plugged fuel line. I would take the fuel line off at the carb and stick it in a can, crank the engine and see if gas is getting up to the carb. If not you probably either have a plugged fuel filter or a bad pump.
 
#6 ·
colapsed fuel line

Check the fule line. Is it an original line with the wire mesh around it? Years ago I had a simeler problem that about drove me crazy. When the engine would heat up it would heat the rubber fuel line and after driving a while the cold gas would cause rubber to colapess and shut off the gas from going into the fule pump. It took me a while and some sleepless nights to figure that one out.

Good Luck

Mike
 
#7 ·
Disconnect the fuel line at the carb, maybe put a hose extension on it and see if you can shoot some into a cup when cranking the motor. Might tell you if fuel is getting blocked inside the carb at least, and prove there is no blockage after the pump and the pump is working.
 
#8 ·
jchochole, If you are sure that the fuel pump is working properly, you need to systematically eliminate the issue, the fuel line could be plugged somewhere, you could flush it out with denatured alcohol. then I would check the fuel filter. If new make sure it is on right, then check the carburetor. make sure that the fuel line is not plugged, then check the jets to see if any obstruction exists, and also the floats could need replacing. These are just some easy trouble shooting steps. Also make sure there are no air leaks between the carburetor and the manifold. Just a few thoughts. Some one else might chime in here. Best of luck with your fuel aspiration issues. MERRY CHRISTMAS.:anim_25: :blowtiedb: :flag4:
 
#12 ·
Another tip to troubleshoot the fuel pump is to disconnect both lines from the pump.Hold a finger over the input fitting and crank the eng. and feel for suction.If no suction is evident,replace the fuel pump.If there is suction blow out the fuel line to the tank with low press.compressed air until bubbling is heard from the fuel filler neck.Also blow out the carb fuel line,both ends disconnected.Hope this helps.Good luck. Big Bob U.S.A.F.66'-70'
 
Discussion starter · #13 ·
Fuel Issues

Thanks for all the tips. Yes, I have about 5 gallons in the car and I did turn the motor over but didn't get any fuel in a jar from the pump/line.

Next steps:
I'll disconnect the lines from and before pump and turn car over- I suspect this may be either the original or very old pump- fuel lines are original and this car hasn't been restored. The gas tank is original, although I drained it and the fuel was fairly clean. I am gonna add another filter to the line once I get her started- the only existing filter is that goofy copper porous block that is generic for 70's cars.

Thanks for the next steps- it may sound simple and routine to most of you guys but for a newbie like me- this is golden advice.

Thanks for all the support and help- I couldn't enjoy my car without you guys!

Jim from Oswego
 
Discussion starter · #15 ·
Update

Alright- spent all day isolating issues. Car still won't stay running.

1. added new fuel pump
2. fuel line is clear and blows gas up to pump- with compressed air.
3. car runs if I dump gas into the carb manually- but only runs about 10-15 seconds- then dies.


I suspect my old 1-barrel carb needs professional help! I tried to rebuild it but I am unskilled in carburetion. Does anyone do simple rebuilds?

Thanks,
Jim
 
#16 ·
jchochole said:
Alright- spent all day isolating issues. Car still won't stay running.

1. added new fuel pump
2. fuel line is clear and blows gas up to pump- with compressed air.
3. car runs if I dump gas into the carb manually- but only runs about 10-15 seconds- then dies.


I suspect my old 1-barrel carb needs professional help! I tried to rebuild it but I am unskilled in carburetion. Does anyone do simple rebuilds?

Thanks,
Jim
Click to expand...
If you are getting gas through the line now , I would suspect a stuck float valve. Remove the carburetor, drain any gas out of it, and blow into the gas inlet. If you can't blow into it the float valve it needs to be freed up. (carb rebuild) A new carb pump wouldn't hurt.
 
#17 ·
jchochole said:
Alright- spent all day isolating issues. Car still won't stay running.

1. added new fuel pump
2. fuel line is clear and blows gas up to pump- with compressed air.
3. car runs if I dump gas into the carb manually- but only runs about 10-15 seconds- then dies.


I suspect my old 1-barrel carb needs professional help! I tried to rebuild it but I am unskilled in carburetion. Does anyone do simple rebuilds?

Thanks,
Jim
Click to expand...
Do you have a shop manual. A lot of good information about the carburetor in there.
 
Discussion starter · #18 ·
Carb Issues

I bought a new carb rebuild kit and added a new accelerator pump, seat and needle valve. I pulled the carb apart today and got the needle valve working well...stuck it back onto the engine and no start???

Frustratedly- this little 1bbl is so basic yet it stumps me!

I can still pour gas into the carb and she runs- otherwise it never pops! Maybe I ought to admire failure and buy a rebuild carb and turn this in as a core? Does have some leakage at the base.

Any ideas?
Jim
 
#19 ·
I am sure you checked this but are you actually getting fuel to the carb? If you are, save yourself a little aggravation and get another carb from a good rebuilder. There are a couple in Hemmings that I have used over the years. I used to do my own rebuilds until I got one from a real pro. Never gave me a moments problem. My own rebuilds always did. There are things to save money on and things not to. I think this might be time to treat yourself!
 
1 - 20 of 29 Posts
About this Discussion
28 Replies
12 Participants
Last post:
Dragsix
Chevy Tri Five Forum
posts
2.6M
members
72K
Since
2005
A forum community dedicated to 1955, 1956, and 1957 Chevy owners and enthusiasts. Come join the discussion about restoration, engine swaps, reviews, performance, modifications, classifieds, troubleshooting, maintenance, and more! Open to all models including Belair, 210, 150, Sedans, and Nomads.
Full Forum Listing
Explore Our Forums
Chit Chat Area, Anything on your mind goes here. New Member Introductions Stock Chevy Discussion 55-56-57 Project Update Section, Post Project Updates Here Suspension Questions Chassis, Brakes, Shocks, Etc