The 'Surge' (not the military type)

[Omni Source]

Good Day All

The '71 Bee has been in long storage. Got it out a couple of week ago, dusted it off, changed the oil and fuel filter, checked everything, went for a cruise. Everything worked like it should (except for the cruise control). Roasted the tired a couple of times filled the gas (93 octane). Had an exhaust leak which ended up being the choke thermostat pocket gasket. Unfortunately, when troubleshooting this, I ended up removing the intake. That ended up with the carb coming off to replace the base gasket. Since then I've got it out when weather permits and all was well.

Today, I took it of to my alignment guy. On the way home it stalled in traffic. Restarted okay, but the acceleration is not smooth. Once out of town the hammer dropped. When the speedo reached 50, the motor started to surge like you were stepping on the gas, then removing your foot, and stepping on it again. It did not stall.

Once home I checked the timing, fiddled with the carb as per the shop manual, all to no avail. The car starts fine, drops to curb idle when you tap the gas. When you take it out there is a 'dead-spot' when you accelerate (approx at 1/3 throttle). and it will start to surge when you reach 50 mph.

The Bee is a 383 automatic with a Carter AVS.

Any thoughts?

 

[Bigal75]

Plugged fuel filter or dirt in the carb would be my guess. Surging is usually caused by a lean condition.

 

[Omni Source]

Good Morning

Thank You Rapid Robert for the tip on the inlet screen. I didn't know that existed.

Anyway, the screen and the filter are both clean, so I'm doubtful is any debris is in the carb.

The fuel tank is below 1/2 full, so I'm going to remove the pick-up assembly and check the filter in there. If that is also clean, what about a fuel pump malfunction?

Omni

 

[Danomt]

Check fuel volume at the carb, 1 oz per second is good.

 

[Hugh Jass]

The rubber

 

[Hugh Jass]

A rubber fuel line could be collapsing internally and restricting fuel delivery. The cost of replacing them is nothing compared to grief.

 

[Photon440]

Perhaps there's a crack or leak in the ported vacuum line.

 

[SlinktRR]

Happens when lean like bigal said.. Richen your cruise jetting (metering rods) until it goes away. Happened to me with the same setup.

Wont hurt to check for vacuum leaks but I would go richer on the carb. Takes 5 minutes while you are out driving, take a screwdriver and some metering rods in the glove box.

 

[Omni Source]

Good Evening All
The 'surge' as been purged!
The culprit was the fuel pump. Replaced the rubber line from the pump to the steel frame line for good measure. The bee now runs like a scalded cat. Just need to tweak a off idle bog with a little more carb fiddling.

Thanks to all who took the time to respond.

Omni