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1969 modified · 04-06-2005, 12:28 PM

I am running a one barrel carb on a 230 Cu. In engine. Engine and carb only have 49K miles on them, but haven't been ran very much in recent years. I went ahead and put a kit in the carb since the gaskets were leaking somewhat. I have rebuilt carbs for many years many Q-Jets but this is my first go around on this type of 1 barrel. My two problems. After the engine runs for a period of time, you can shut the engine off and come back 1 hour, 2 hours, next day ect. carb won't quirt enough fuel to fire the engine. If you spray a little gas down the throat, she fires right up and runs down the road. I suspicioned the new accelerator pump, but seems to be fine. Second problem is....engine has hesitation unless choke is about a quarter in the shut position.

Thanks for the help in advance.

neonlarry · 04-06-2005, 02:24 PM

Sounds like either accelerator pump (look down carb throat and pump pedal), float level set way too low or fuel is leaking from bowl while it sits.

CHEVIBUBBA · 04-06-2005, 04:27 PM

pull your dipstick & smell it.if you have a strong fuel smell it may be leaking into the engine from the bowls or from the fuel pump.
more likely your fuel pump has a hole in diaphragm.
won't provide correct fuel pressure & can syphon fuel from the carb/line back into tank or into the crankcase.
is the hesitation present at all rpms or just at low rpms?

1969 modified · 04-07-2005, 10:13 AM

I've taken the fuel line loose at the carb and cranked the engine. I've got plenty of fuel. I don't know the exact pressure, but plenty of fuel is flowing. I checked the float level again and it checks out o.k. While I had the top of the carb off, I was pressing down on the accelerator pump and its not shooting out a stream into the throat. Its actually backing up out of the hole that has the checkball and t-plug in it. I'm thinking I may still have a clog between the accelerator pump housing and the output into the throat. Sounds like I need to tear the thing apart again. I soaked it in my carb tank for many hours and blew everything out with a air nozzle, but I may still have a clog somewhere.

04-06-2005, 12:28 PM	#1
1969 modified Registered User Join Date: Aug 2004 Posts: 38	Carb Problem I am running a one barrel carb on a 230 Cu. In engine. Engine and carb only have 49K miles on them, but haven't been ran very much in recent years. I went ahead and put a kit in the carb since the gaskets were leaking somewhat. I have rebuilt carbs for many years many Q-Jets but this is my first go around on this type of 1 barrel. My two problems. After the engine runs for a period of time, you can shut the engine off and come back 1 hour, 2 hours, next day ect. carb won't quirt enough fuel to fire the engine. If you spray a little gas down the throat, she fires right up and runs down the road. I suspicioned the new accelerator pump, but seems to be fine. Second problem is....engine has hesitation unless choke is about a quarter in the shut position. Thanks for the help in advance.

04-06-2005, 02:24 PM	#2
neonlarry Registered User Join Date: Feb 2002 Location: Vacaville, CA Posts: 2,746	Sounds like either accelerator pump (look down carb throat and pump pedal), float level set way too low or fuel is leaking from bowl while it sits. __________________ 70 C/10 Light Red 350/TH350, HEI, Duals w/40 series Flows, 91 seat, LED taillights 99 Pontiac S/C GTP, SLP Ram Air hood, GMPP Konis & springs 95 Neon ACR, MP PCM, AFX UDP, 3.0 CAI

04-06-2005, 04:27 PM	#3
CHEVIBUBBA got boost? Join Date: Mar 2005 Posts: 123	pull your dipstick & smell it.if you have a strong fuel smell it may be leaking into the engine from the bowls or from the fuel pump. more likely your fuel pump has a hole in diaphragm. won't provide correct fuel pressure & can syphon fuel from the carb/line back into tank or into the crankcase. is the hesitation present at all rpms or just at low rpms? __________________ '70 chevy lwb w/'67 hood. 357 s.b.c. built, 4l60 w/vigilante lockup high stall converter, edelbrock pro-flo,brodix heads,comp cams rollerized w/ belt drive, one piece d-shaft, yada, yada, yada..... '82 honda v45 sabre"the black"

04-07-2005, 10:13 AM	#4
1969 modified Registered User Join Date: Aug 2004 Posts: 38	I've taken the fuel line loose at the carb and cranked the engine. I've got plenty of fuel. I don't know the exact pressure, but plenty of fuel is flowing. I checked the float level again and it checks out o.k. While I had the top of the carb off, I was pressing down on the accelerator pump and its not shooting out a stream into the throat. Its actually backing up out of the hole that has the checkball and t-plug in it. I'm thinking I may still have a clog between the accelerator pump housing and the output into the throat. Sounds like I need to tear the thing apart again. I soaked it in my carb tank for many hours and blew everything out with a air nozzle, but I may still have a clog somewhere.



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