Thread: possible carb issues

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When turning over my chevy 350 it dosnt fire at all. I know my timing is close, I know I am getting spark and I can see fuel squirting out of the jets when I pump the throttle. My assumption is that possibly something inside of the carb is jammed not allowing the fuel through to the intake ? The carb is a edelbrock from the performer series if it helps any.

carb is least likely if you're squirting fuel.... check your ignition thats ussually where the problem is... pull a plug, spark test it, see what kind of spark it is... you need a nice rich blue one... even a weak blue one is a fail in my book, let alone a yellow spark...

When I checked the spark it was big and yellow. I just bought a performance accell coil, accell wires and I have an MSD ignition module in my distributer. What would cause the spark to be week?

i'd guess the accel parts... check the resistance in the wires... should be around 2k per foot.... if they all check within those lines... then check the coil, should have relatively low resistance on the primary circuit, and very high resistance in the secondary.... primary circuit is the power side to the points side... secondary is power side to dist. cap side... remember if the spark looks weak outside of the cylinder... then inside it probably isn't sparking at all

Since im just upgrading the wires and coil from stock and had this same problem with the stock wires and coil I would like to throw out the possibilty of spark being an issue in this thread.

For some reason I have lack of fuel stuck in my head. Is there no possible way the carb could be jammed up some where and not allowing fuel into the intake?

It is not firing in any way shape or form. It dosnt backfire, it dosnt misfire it dosnt evan attempt to run. I understand that is a great candidate for lack of spark but I saw the spark from stock parts to the new accell parts and the spark is now 3 times the size it was before.

Your sure you have the initial timing right? Is this a first start, or was it running before?

have you tried just taking the carb off with the fuel bowls having gas in them, and then pulling the throttle and seeing if its coming out the bottom and working correctly in that sense?

Originally posted by 4speedTerror
Your sure you have the initial timing right? Is this a first start, or was it running before?

Im not sure the timing is dead on but it should be close enough to where I would at least get a backfire from one end or the other. I had it running once before but it just one day decided to not start again. It was always a PITA to get started but now I get no kind of firing at all.

Originally posted by daveid
have you tried just taking the carb off with the fuel bowls having gas in them, and then pulling the throttle and seeing if its coming out the bottom and working correctly in that sense?

I have had the carb off but did not open the throttle. I will try this soon.

It must be spark. Just the shot of gas from the accelerator pump will start the engine. Unless your gas has gone rotten? How long has it been in the tank?

Simple question: did you remove the distributor to install the Accel components?

Originally posted by nystreetscene
Im not sure the timing is dead on but it should be close enough to where I would at least get a backfire from one end or the other. I had it running once before but it just one day decided to not start again. It was always a PITA to get started but now I get no kind of firing at all.

I'm really thinking it is your timing. You don't necessarily have to get a backfire if it was off. I was playing around with my timing a few weeks ago advancing it bit by bit. At one point it was running well, but when I went to start it again, the engine would not fire too. I was getting, what I am guessing, a slight amount of kickback when cranking. I’ve only read about that part on these forums, so I’m not sure if that was the case or not, but something just didn’t “feel right”.

I retarded the timing just the last little bit and it fired right up, and there was no apparent missing or backfires.

Originally posted by R Pope
It must be spark. Just the shot of gas from the accelerator pump will start the engine. Unless your gas has gone rotten? How long has it been in the tank?

The gas is pretty fresh with in a couple of weeks.

Originally posted by robot
Simple question: did you remove the distributor to install the Accel components?

I did not remove the distributer to install the accel components.

Originally posted by pelligrini
I'm really thinking it is your timing. You don't necessarily have to get a backfire if it was off. I was playing around with my timing a few weeks ago advancing it bit by bit. At one point it was running well, but when I went to start it again, the engine would not fire too. I was getting, what I am guessing, a slight amount of kickback when cranking. I’ve only read about that part on these forums, so I’m not sure if that was the case or not, but something just didn’t “feel right”.

I retarded the timing just the last little bit and it fired right up, and there was no apparent missing or backfires.

I checked my carb, I am getting fuel and I ran a ground from the frame to the motor and a ground from the cab to the motor. Still assuming my coil and wires are fine I guess the last thing I have is timing.

I checked my carb, I am getting fuel and I ran a ground from the frame to the motor and a ground from the cab to the motor. Still assuming my coil and wires are fine I guess the last thing I have is timing. [/B][/QUOTE]


If you didn't have grounds before from the engine to frame and engine to firewall, chances are you fried both coils. It doesn't take long, especially with a high performance coil and module. Plugs are most likely fouled also. Been there, done that. Also explains why hard to start. New plugs and new coil will most likely get you fired back up. You can check the coil as stated earlier in the post. Check spark with a new plug and if it's anything other than blue, coil is most likely burnt.

Originally posted by camaro_fever68
If you didn't have grounds before from the engine to frame and engine to firewall, chances are you fried both coils. It doesn't take long, especially with a high performance coil and module. Plugs are most likely fouled also.

i forward that motion... i've gone thru the same problems recently with my mustang... when i thought i had fixed the ground issue i had been stuck thinking that the plugs were still good.... but they were all fouled up

[QUOTE]Originally posted by thesals
[B]i'd guess the accel parts... check the resistance in the wires... should be around 2k per foot....

2k per foot is unacceptable, should be less than 500 ohms.