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Discussion Starter #1
Greetings Everyone!

I apologize upfront, this may seem like an easy question...

I have a 2 barrel Autolite carb on my '69 Mustang and I noticed that I am running pretty rich.

I was looking into how to do this and it looks like i can potentially do this by adjusting the choke and/or the idle mixture screws.

I was hoping to get some pointers/suggestions on the best way to go about doing this and which to start with.
 

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Running rich when?

After warmup. The choke plate should be vertical and not affecting the air flow.

If rich while running and warm, jets are too big. Drop 2 sizes down and check again. Ie;if you have 62 jets in it, put in 60's and check it after a 30 minute run

Sent from my SM-N960U using Tapatalk
 

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Also check the float as the solder on them gets eaten by the ethanol in todays gas and could make the float heavy...
 

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Discussion Starter #4
Running rich when?

After warmup. The choke plate should be vertical and not affecting the air flow.

If rich while running and warm, jets are too big. Drop 2 sizes down and check again. Ie;if you have 62 jets in it, put in 60's and check it after a 30 minute run

Sent from my SM-N960U using Tapatalk
It is rich at cold start and when running warm.
Is it easy to adjust the jets?
 

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Discussion Starter #5
Also check the float as the solder on them gets eaten by the ethanol in todays gas and could make the float heavy...
The Carb is new as of 2019, but that doesnt mean something isnt messed up. That is a good thought. just hate taking it apart though.
 

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First, insure the choke plate is pulling off Vertical when warm. Have anyone "fiddled" with the mix adjustment screws?
Do you have an engine VAC gauge? If not buy one, if you plan on keeping this gem.
 

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Discussion Starter #8
First, insure the choke plate is pulling off Vertical when warm. Have anyone "fiddled" with the mix adjustment screws?
Do you have an engine VAC gauge? If not buy one, if you plan on keeping this gem.

The carb was installed by a local shop so i do not know if they have adjusted the mix adjustment screws. I do not have a vac gauge. I have recently noticed that i am getting some bluish/white smoke coming from the exhaust that i have started a separate thread about as well. I am starting to think the best bet is to simply reset the mix adjustment screws.
 

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The mix adjust screws only adjust for slow running and idle quality. Blue'ish white is an indication of oil bing burned. If this smoke shows at "start up", then, magically disappears, it's an indication your intake valves seals are suspect. If it "doesn't" disappear, it could be an indication of deeper problems, that is, rings? Another think to check the PCV system for proper operation. Have your contacted your shop? Do they "warrant" their work?
 

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Discussion Starter #10
The mix adjust screws only adjust for slow running and idle quality. Blue'ish white is an indication of oil bing burned. If this smoke shows at "start up", then, magically disappears, it's an indication your intake valves seals are suspect. If it "doesn't" disappear, it could be an indication of deeper problems, that is, rings? Another think to check the PCV system for proper operation. Have your contacted your shop? Do they "warrant" their work?
I just ran a test and the smoke is also happening when i am driving with a pretty strong exhaust smell left it its wake. I am starting to think it is head gasket or ring as you suggested. the joys of classics :)
 

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I just ran a test and the smoke is also happening when i am driving with a pretty strong exhaust smell left it its wake. I am starting to think it is head gasket or ring as you suggested. the joys of classics :)
I just ran a test and the smoke is also happening when i am driving with a pretty strong exhaust smell left it its wake. I am starting to think it is head gasket or ring as you suggested. the joys of classics :)
If it appears more "whiteish", check your coolant level and or monitor the level. "White" is more of an indication of a head gasket leaking coolant into the combustion chamber. Depending on where the break is in the gasket, there can be bubbles in the Rad. This can be checked with the cap removed (use caution, if hot) and watching for bubbles and excess agitation as the combustion gases are being pushed into the coolant system.
 
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Discussion Starter #12
If it appears more "whiteish", check your coolant level and or monitor the level. "White" is more of an indication of a head gasket leaking coolant into the combustion chamber. Depending on where the break is in the gasket, there can be bubbles in the Rad. This can be checked with the cap removed (use caution, if hot) and watching for bubbles and excess agitation as the combustion gases are being pushed into the coolant system.
I'll check that this afternoon.
If it appears more "whiteish", check your coolant level and or monitor the level. "White" is more of an indication of a head gasket leaking coolant into the combustion chamber. Depending on where the break is in the gasket, there can be bubbles in the Rad. This can be checked with the cap removed (use caution, if hot) and watching for bubbles and excess agitation as the combustion gases are being pushed into the coolant system.
Could the gasket also be a cause for the engine to overheat? I've noticed that here recently the car itself been running much hotter than normal.
763160
 

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Yep, a leaking gasket can add to over heating.
 

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It is rich at cold start and when running warm.
Is it easy to adjust the jets?
Is it only rich at idle? Or is it rich when cruising? Also how do you know its rich? Did you check out the plugs. Rich idle is easily fixed with idle mixture screws. Rich when driving requires a jet change.
 
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