Base Carb Tuning and the great vacuum leak search.....help (1 Viewer)

Joined
Jan 6, 2017
Messages
96
Location
Kyle Canyon, Nevada
Ok, I'm all put together. Idling ate about 1500 and it sounds good. Vacuum off the gas filter is around 15 and very steady at the 1500 rpm idle. Is there anything else I should do prior to pulling the air cleaned and messing with the carb adjustment?
 
Joined
Jan 6, 2017
Messages
96
Location
Kyle Canyon, Nevada
Update. I've got everything hooked up. And have a nice strong idle down to about 850 rpm. Below that the vacuum gauge and tach begin to bounce and engine sounds real throaty. Stinky visible exhausts at low tons as well.

I haven't touched the idle mixture screw since except two full turns from the bottom.

Do my symptoms suggest idle mixture problem or ongoing vac leak?

Thanks again.
 
Joined
Sep 17, 2010
Messages
1,740
Location
Central Valley, CA
If your vacuum is still around 15 with the 850 idle you are pretty good for that altitude. If your diaghragms on the distributor are inop, and you will be staying at altitude, you can advance the distributor 6 degrees and cap the line going to the secondary diaghragm (outside port).
Keep the Upper 3 lines on the HAC hooked to the carb so the additional air feeds into the carb.

I use the lean drop method to tune the carb along with the help of a vacuum gauge and fine tune it just by feel.
 
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Joined
Jan 6, 2017
Messages
96
Location
Kyle Canyon, Nevada
Just an update. Since this thread I was able to run and drive great for several hundred miles. Thanks again for your help everyone.

It is interesting that prior to this thread I was unable to locate anything super helpful in regards to my situation with the search function. However, since the detailed responses in this thread have vastly improved my vocabulary and suddenly I can find a plethora of other folks in my exact same situation. Also improved my use of the FSM.

So again, thank you, I owe beers.


Further update. It was running too good so the fuel pump decided to start spewing out the bottom . The rabbit hole is dark and deep. Long story short, my tank is at the radiator shop, all new soft lines are installed and waiting. Suck it rust.
 

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