Do you get any black smoke when it does start? Sometimes the float bowls are porous and leak fuel into intake manifold.
Q-Jet Help??? Lars????
Thread Starter
Racer
Joined: Apr 2006
Posts: 322
Likes: 0
From: Rockford MI
Q-Jet Help??? Lars????
I have a stock 78 L 48. It has a Carter manufactured Q-jet on it, number 17059884. (is this a replacement carb? THis number is not listed in NAPA's carb catalog.)
Lately it has been starting real hard when its cold. I have to pump it several times and crank it for quite a while to get it to start. I have removed the air cleaner top when I start itto confirm the choke is closing all of the way. Also when I cycle the throttle, I can see fuel squirting in the carb.
Also, after I shut it down after driving it it smells very strongly like raw fuel. I don't have any leaks, rusty fuel lines, rusty tank, etc. to cause this smell. I pretty sure its the carb. Its enough that it smells the garage up pretty good.
any ideas please?????
Lately it has been starting real hard when its cold. I have to pump it several times and crank it for quite a while to get it to start. I have removed the air cleaner top when I start itto confirm the choke is closing all of the way. Also when I cycle the throttle, I can see fuel squirting in the carb.
Also, after I shut it down after driving it it smells very strongly like raw fuel. I don't have any leaks, rusty fuel lines, rusty tank, etc. to cause this smell. I pretty sure its the carb. Its enough that it smells the garage up pretty good.
any ideas please?????
Drifting
Joined: Sep 2004
Posts: 1,959
Likes: 1
From: North Bend Ohio
Does the choke close all the way when you set it? Have you tried pumping it to set the choke than pumping again after about 10 seconds? This will give it some extra fuel to work with.
BigBlockk
Later.....
BigBlockk
Later.....
Pro
Joined: Apr 2006
Posts: 647
Likes: 22
From: Norwalk CT and Boynton Beach FL
Assuming the car has been tuned up properly, it's probably a problem with your carbuerator float & needle valve combo. Either the float needle valve is worn out and is not shutting off the gas supply to the carbuerator bowl or your float has sprung a leak. If either of these two conditions exist, when you shut off the engine, fuel pressure will continue to fill the carb bowl with fuel which will then spill over and flood the intake manifold with fuel --- giving you the gas smell and hard starting (becuse it's flooded). This is an easy fix and you should also replace the accelerator pump while you're at it.
The right thing to do is get a carbuerator rebuild kit and pull the carb and do a complete carb cleaning and rebuild.
I hate to admit this, but I've actually done a similar fix without ever taking the carb off the engine --- by just removing the bowl cover assembly which gives you access to the float, needle valve and accelerator pump. But doing this is risky in that if you drop one of those little screws or clips down the throat of the carb --- then you have a much bigger job on your hands to retrieve that stuff.
Good luck
The right thing to do is get a carbuerator rebuild kit and pull the carb and do a complete carb cleaning and rebuild.
I hate to admit this, but I've actually done a similar fix without ever taking the carb off the engine --- by just removing the bowl cover assembly which gives you access to the float, needle valve and accelerator pump. But doing this is risky in that if you drop one of those little screws or clips down the throat of the carb --- then you have a much bigger job on your hands to retrieve that stuff.
Good luck
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Burning Brakes
Joined: Oct 2004
Posts: 920
Likes: 1
From: Shelby Township Michigan
I have a similar problem to yours. Have you checked your timing lately? If so, where is it set at?
I start mine by pumping the pedal to close the choke and to spray some fuel into the carb. I usually pump it four times. On the first engine crank, It will not start. I pump the accelerator 4 more times and crank the engine again. Sometimes start, but not likely. On the third try, it fires up just fine. Goes to high idle and runs smooth. I believe this has something to do with the total timing setting I have.
Good luck. I am curious to see what you find.
Dino
I start mine by pumping the pedal to close the choke and to spray some fuel into the carb. I usually pump it four times. On the first engine crank, It will not start. I pump the accelerator 4 more times and crank the engine again. Sometimes start, but not likely. On the third try, it fires up just fine. Goes to high idle and runs smooth. I believe this has something to do with the total timing setting I have.
Good luck. I am curious to see what you find.
Dino
Drifting
Joined: May 2005
Posts: 1,629
Likes: 4
From: Somers CT
JB Weld works very good, available at most hardware stores. This is a pic of mine when I took it apart, they were leaking really bad. Clean them up with acetone or other good solvent that doesn't leave a residue. As you can see someone was in there before with something that didn't work very well
Former Vendor
Joined: Nov 2006
Posts: 2,482
Likes: 3
From: Carmichael ca
If you're having this many issues, you'd probably be better off buying a new(not rebuilt) carb. Does holding the throttle open slightly help the car start easier? If so, then its probably flooding.
Race Director
Joined: Jul 2002
Posts: 13,858
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From: A 12/8 man in a 4/4 world
Tech Contributor
Joined: Aug 1999
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From: At my Bar drinking and wrenching in Lafayette Colorado
