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post #1 of 7 (permalink) Old 05-09-2015, 06:30 AM Thread Starter
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tuning?

Hi awesome people.............way too long.
We were out driving the Goat, we have around 2oo miles on the 2nd rebuild and runs great but, seems to idle a bit too high and has obvious miss issues.(every few seconds?) people told me they think it may be running to rich.
The 'miss' is most noticeable idling at a stop.
what might I do to attempt to correct this?
thanks as always and super best wishes to everyone here !!
Tk
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post #2 of 7 (permalink) Old 05-09-2015, 06:25 PM
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TK! Long time my friend... how be you?

Idle speed is easy... look for a screw on the side of the carb, on the linkage, same side as where the throttle cable connects.

Idle mixture is the two screws on the front of the carb, down low. 'Right' way to do this is with a vacuum gauge - adjust both evenly for the highest vacuum reading. If you don't have a gauge, you can approximate by slowly turning them in (clockwise) equally until it starts to run rough. Back out until it smooths out.

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post #3 of 7 (permalink) Old 05-10-2015, 06:16 AM Thread Starter
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Thank you brother Bear!
Good to hear from you lad, I am very well thank you, hope you are the same!
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post #4 of 7 (permalink) Old 05-10-2015, 06:54 AM Thread Starter
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I'm going to see if auto zone has an appropiate vac. gage.
I read that I need a constant vac.
How do I proceed from here?
thanks as always!
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post #5 of 7 (permalink) Old 05-12-2015, 08:42 PM
 
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TK Bear gave you the right place to start, a bad mixture can cause missing, as the mixture is wrong too rich or too lean and therefore some cylinders won't fire, or one won't fire.

If that does not help the next two things are mechanical ( compressions) or electrical. If you are sure the the mechanical is OK the electrical is relatively easy. Remove a spark plug wire and use a spark tester, a few bucks at auto parts store or just an alligator clip boot to ground on one wire.

Find the one that has a weak spark, if you can see it with the tester, or the one where, when it is grounded there is no change in the observed "missing" when they are all connected. Of course scopes, spark pens all can be used as well. But a miss can be found this way.

Then track it back, spark plug? plug wire bad? Dist cap? Rotor?......

Good luck ...you will find it!
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post #6 of 7 (permalink) Old 05-13-2015, 10:02 PM
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A good place to connect the vacuum gauge is to "T" it into the line that goes to your power brake booster, or any other available connection that is direct to the intake manifold and not the carb. The only reason I say "not the carb" is you have to be aware which connection points are ported vacuum and which ones are non-ported vacuum (you want to use a non-ported source for this), and its just easier to use a direct to the manifold connection. If you have to use a carb connection, make sure the engine is a running at a very slow idle, hook a hose to the port you want to test, and feel it with your finger. If you feel vacuum (engine at a low idle) it's a non-ported source and ok to use.

I'd start by turning both the screws in until they bottom, then back them both out a precise full 3 turns. This setting will probably be too rich and that's ok. You want to SLOWLY sneak up on the setting coming from the 'rich' side. It can take a few seconds for the engine to respond to the change, so make your changes slowly and evenly (same amount on both sides at the same time).

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post #7 of 7 (permalink) Old 05-24-2015, 01:11 PM Thread Starter
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I turned the 2 mixture screws all thee way in and counted a tad over 2 1/2 turns.......then backed them out to 3 and it ran worse. 2 turns and 2 1/4 wernt any better. It still misses. I will remove the plugs and check the gap.........
When checking the spark, are you guys talking about the plug removed and plugged in and just holding the wire and looking at the spark?
thanks as always and happy Memorial day all!!
Tk
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