Stuttering Mutt

[42GPW]

I have a jan 67 mutt. It stutters when shift to 2nd or 3rd (like its not getting fuel). Cleaned the tank out, fuel lines out, Replaced the Carb, with a brand new NOS carb. New plugs, and Roter, wires, points, and condenser. Am i possibly having a timing problem?

Matt R

[rickf]

Matt, See the sticky at the beginning of the tech section, All of the settings need to be right on before the carburetor will work correctly or can be diagnosed.


Rick

[42GPW]

Tha carb is set. It idles great. It drives great in 1st gear. When i shift it stutters.

[rickf]

That is because there is almost no load in first gear, when you shift to second there is more load. It sounds like an accelerator pump issue but you have changed carbs with the same symptom.Valve adjustment and timing will both have an affect on engine vacuum. Vacuum is what the carb needs to run right and also operates the accelerator pump. You have thrown a lot of parts at it and cleaned or replaced all of the pertinent items. You asked if you might have a timing problem. The answer is "yes you may, but you also need to check the valve adjustment. One valve that is too tight by .002 or .003 could really screw up the vacuum signal therefor everything down the line.


Rick

[halftracknut]

Check the oil in your air cleaner....this creates vac. toooooooooooo.....HTN

[rickf]

Check the oil in your air cleaner....this creates vac. toooooooooooo.....HTN

True, It does, but on the wrong side of the carburetor. Just another reason for all of the above mentioned items to be spot on. The carburetor should be the last thing checked after all of the tune up items are done.


Rick

[42GPW]

I found the problem with the stutter. My fuel tank well (where you fill it) was cracked at the seam of the spout. Even though i would have it capped. It still needed to be sealed due to the vacuum. So basically a hole in my tank was the issue. Thought some of you would like to know. Its been bugging me for a while. Now i can focus on the rear diff. And soon enjoy a ride. Once it gets warmer. Thanks for all your help.

FYI. This was not figured out by me but a friend from work tht was a mecanic in Vietnam.

Matt R