Symptoms you are describing sound similar to ones I encountered. When cold the engine started without incident but as it warmed up it started backfiring and lugging when shifting to higher gears. I thought it was a timing problem, valve, fuel delivery, carb issue. After replacing the mechanical fuel pump with an electric one, swapping out carb, checking adjustment on values I was not having any improvement.

When you had the points replaced/adjusted was the capacitor replaced. What one of the members recommended was checking the temperature of the capacitor, if it was hot then it may be breaking down as engine warms up. Replaced capacitor and problem was solved.

I’ll assume that you checked the choke.  ??  If not, shame on you.

Capacitors are easy to replace and cheap.  Change it first.

Could be the fuel pump, but unlikely.

The next time that it acts up, take a plug wire off and stick a phillips screwdriver into the end that normally goes on the spark plug.  Holding the screwdriver close to anything on the engine that is metal, get your wife to crank the engine for a turn or two.  If you get a spark, you can be pretty sure that your problem is NOT distributor or spark related.  = fuel.  Try changing the fuel filter – this is probably not it, but once again, they are cheap and easy to replace.  If that doesn’t fix it, you could hook a pressure gauge in the fuel line and check the pump.

Ed’s right it does sound like a symptom of carb icing.  But carb icing in south Florida?  I have never experienced icing, so check the temperature of your inlet manifold just below the carburetor.

Mine is like this too, a little bit. I believe your car is IRS (double-jointed) like mine. Roy is right that the torsion bars are probably a little out of adjustment, and that, in our cars, you can’t get to the caps without unbolting the tub.

I believe that the torsion bar bushings are also the problem. They tend to wear unevenly, and they contribute more to the /| effect than the bar indexing itself does.

The problem is only slightly easier to correct than the torsion bar index, however: you still have to get the end caps off, which means you still have to get the body off first.

I plan to do mine next year….

• This reply was modified 6 years, 11 months ago by edward ericson.

I’m curious.  If the rear wheels are not parallel, are you experiencing uneven tire wear?  Being a worrier, I also wonder if TDrs can have similar errors in the other plane – left to right, probably as a result of an accident.

• This reply was modified 6 years, 11 months ago by Rich Kallenberger.

Hi,  if your wheels look like this/  | then i think it a safe bet you have a wheel bearing problem or  missing bushing  in the axle support. irs  trans don’t let the wheels tilt in or out like a swing axle trans. look over in the samba forum there are some mighty sharp minds  who know and can advise you better than i.

just look over in” new to forum ” forum and you will see that Paul send photo of irs pan which shows how wheels  and supports are attached. cannot think your body would need removing.