Back firing 74 Cherokee AMC360

[TylerII]

My 74 cherokee backfires when at idle...not loud but little thunking noises almost as if the back window were banging around. This happens when at a stop or if I take my foot off the gas while driving. Someone told me this could be fixed by advancing the distributer and possibliy tuning the carb. I'm not sure which carb I have because it's shinier than the rest of the engine and doesn't look stock...I do know that it has an edelbrock (performer?) manifold. My questions are:
1. Will advancing the distributer fix this problem? And,
2. If it will, how is this done? Thanks in advance.

[The Anti-Chrysler]

Not necessarily advancing it, but making sure it's set right will definitely help. You'll need a timing light to do the job. Basically you just hook up the timing light to the #1 spark plug wire (front left cylinder), plug the vacuum line to the distributor after you remove it (important), and set it with the light, rotating it until the timing marks on the front end cover of the motor line up with the proper timing setting for your engine. I recommend a shop manual if you've never done this before. You can do the timing without the light by trial and error (checking for pinging), but you are best with the light if you're a novice at this. Hope this helps.

[TylerII]

Thanks Jason. I'll see if that helps. In the mean time I discovered that my rear U-joint has cracked so I'll be learning how to replace one today.