Carb issue
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5th Wheeling
Joined: Mar 2024
Posts: 34
Likes: 4
Carb issue
Okay, guys, check this out. I took off the VV car and installed an Autolite 2100 months ago. She started and ran great until yesterday, but I have not run her this many miles at once either. Normally just raound town. After running about 100 miles, I will stop for gas. I leave it running. As it idles for about a minute, it will slow and run rough, then shut off and not restart. She did this three times each after about 100-plus miles oneway-running highway speeds. I carry extra parts just to be safe. I have swapped the ignition box and coil with no change. On the positive, she will restart after sitting for about 30/45 minutes and run like a champ until the next leg of the trip is complete. She has no issues idling around town.
Another thing that could be the culprit, but I am no expert. She runs really rich. The tailpipe is black, and I had to replace the plugs for about three months due to complete carbon buildup. If I back the mixture screws out any further, they will fall out. Could the card just need to be rebuilt? I am thinking of buying a new/rebuilt one. If so, where do I need to purchase one? What are your thoughts?
Another thing that could be the culprit, but I am no expert. She runs really rich. The tailpipe is black, and I had to replace the plugs for about three months due to complete carbon buildup. If I back the mixture screws out any further, they will fall out. Could the card just need to be rebuilt? I am thinking of buying a new/rebuilt one. If so, where do I need to purchase one? What are your thoughts?
Lead Driver
Joined: Nov 2013
Posts: 7,155
Likes: 1,167
A good starting point is to gently turn them all the way in, then back out about 1.5 turns. Experiment from there, making fine adjustments as needed.
While you’re at it, consider this modification for easier access to the adjustment screws:
https://www.ford-trucks.com/forums/1...re-screws.html
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5th Wheeling
Joined: Mar 2024
Posts: 34
Likes: 4
Hey Karl, I screwed them in all the way, backed them out 1.5, and ended up about 2.25. She idles great. Once she got hot, she briefly idled rough and quit this morning in the driveway and did not want to restart. I think she runs too well down the road and at idle to be the carb, although the mixture was most definitely rich. Hopefully, I will have that issue resolved. Now, we just need to tackle the shutting off. I also replaced the electrical ignition switch at the base of the collum in January since it was questionable. No issues since it was replaced until this week. On another note, I am not completely sold that the new Standard brand Chinese coil from Napa is not breaking down at idle when it gets hot. I am heading to another parts house this morning to pick up another brand.
FTE Legend
Joined: Nov 2015
Posts: 30,832
Likes: 4,097
From: Angier, NC
You are going to need to do some testing when it stops running so you know what path you need to go down for a fix, spark or fuel?
Next time it stops running pop the air filter off, choke should be open all the way, Look down the carb and move the throttle do you see fuel squirt?
This part will be a little hard but you need to check for spark. pull the coil wire out of the cap and get it to stay about 1/8" from ground.
When cranking the motor you should see a nice blue spark and hear a snap when it happens.
Once you check the 2 things above let us know what you find and we can move on from there.
Dave ----
Next time it stops running pop the air filter off, choke should be open all the way, Look down the carb and move the throttle do you see fuel squirt?
This part will be a little hard but you need to check for spark. pull the coil wire out of the cap and get it to stay about 1/8" from ground.
When cranking the motor you should see a nice blue spark and hear a snap when it happens.
Once you check the 2 things above let us know what you find and we can move on from there.
Dave ----
Moderator
Joined: Jan 2001
Posts: 56,951
Likes: 2,718
From: Virginia
Hey Karl, I screwed them in all the way, backed them out 1.5, and ended up about 2.25. She idles great. Once she got hot, she briefly idled rough and quit this morning in the driveway and did not want to restart. I think she runs too well down the road and at idle to be the carb, although the mixture was most definitely rich. Hopefully, I will have that issue resolved. Now, we just need to tackle the shutting off. I also replaced the electrical ignition switch at the base of the collum in January since it was questionable. No issues since it was replaced until this week. On another note, I am not completely sold that the new Standard brand Chinese coil from Napa is not breaking down at idle when it gets hot. I am heading to another parts house this morning to pick up another brand.
First thing to do is check the suction line to the pump. Follow it along and see if it's near any heat sources. For some reason I have had long lengths of rubber line aggravate this problem so if someone has replace the line going to the tank or long portions of it with rubber line I would suspect this is part of the problem.
I had this problem with my Bronco II the last couple of years. The factory ran the line around the frame on the driver's side and it ran right beside the exhaust manifold. I put insulation around this line and it helped, but on really hot days it came back. I finally ended up abandoning the mechanical fuel pump on the engine, and putting small electric pump on the frame just ahead of the fuel tank. Problem solved.
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5th Wheeling
Joined: Mar 2024
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Yeah it's not the fuel. I tested the coil. It tested good. Even swapped it out with a brand new Blue streak to be on the safe side. I put the spark tester on the front plug. Fired it up. She ran perfect. A good 15 minutes solid spark on the tester. The spark started becoming intermittent and them would appear every so often until it finally shut off. Starting it back up it looks to have a weak spark. When it does fire up and give it some gas the spark looks great.
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5th Wheeling
Joined: Mar 2024
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5th Wheeling
Joined: Mar 2024
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All right, I misread. I'm getting 7.3 volts to the coil on the hot side. Does this hot side go to the electric ignition switch on the steering column?
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Joined: Jan 2001
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From: Virginia
In a round about way, yes. It does go through a resistor to drop the voltage though. When cranking you should get full battery voltage, when running you should get a reduced voltage, something around 9 volts or so.
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