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Wed Oct 02, 2013 5:07 pm

It's been a while since I've been on here, but now I have a good reason to be. My 72' super beetle is running like garbage and I can't make heads or tails of it. When it starts, it revs up (to 1000 rpm on the first notch of the choke cam) way too much, has no power when taking off from a stop, and dies every time I slow down or stop. I replaced the solenoid a long time ago, it still works, I've done every carb adjustment in the book and online, and I'm still getting nowhere. Also, the idle will sometimes jump from a boggy rumble to almost flat-out by itself. This car is my DD, and I really need to let my mom drive her own car once in a while, so any suggestions would be welcomed!

Wed Oct 02, 2013 5:08 pm

I also forgot to mention that I just fixed an exhaust leak on one of the front head ports.

Wed Oct 02, 2013 6:03 pm

First, try timing it with the distributor / belt. Also, your choke looks like it's sticking and acting up. See if you can adjust the choke.

Wed Oct 02, 2013 6:35 pm

Already did that. The choke is brand new and is adjusted, and the timing is where it should be. I've got a mark on the pulley for max advance, and when the engine gets up high enough, it touches the v-belt on the right side. The 7.5 degree notch lines up with the crankcase mark at idle. Out of curiosity, how would I know if the vacuum advance is working while the engine is running? And is it possible that the weights in my DVDA distributor could be sticking every so often?

Thu Oct 03, 2013 2:25 pm

65'1300Deluxe wrote: ... and the timing is where it should be. I've got a mark on the pulley for max advance, and when the engine gets up high enough, it touches the v-belt on the right side.
Hmmm, are you sure this isn't the BDC (Bottom Dead Center) mark?
I've heard of checking max advance with the TDC mark rotating counter-clockwise under the strobe light until it touches the fan belt on the left side of the pulley, but not what you described?

65'1300Deluxe wrote: The 7.5 degree notch lines up with the crankcase mark at idle.
Do you have both vacuum hoses connected to your DVDA distributor? If so, at idle you should read 5ATDC instead of 7.5BTDC. If you are timing it with all hoses disconnected and plugged, 7.5BTDC is about right.

65'1300Deluxe wrote: Out of curiosity, how would I know if the vacuum advance is working while the engine is running?
At idle, find a vacuum port on the carb or intake that had strong vacuum. The vacuum retard port on the rear face of the carb should work, or if you have an intake port on the down pipe it would work too.
Check your idle timing with all hoses disconnect from the distributor vacuum can. Then connect your vacuum advance port to the strong vacuum. You should see the timing mark jump 8-12 deg. Engine rpms will also change.
You can do a similar test with your vacuum retard. Expect to see the vacuum retard take away 8-12 deg of timing. 7BTDC should turn to 5ATDC.

65'1300Deluxe wrote: And is it possible that the weights in my DVDA distributor could be sticking every so often?
Sure.
With the vacuum hoses disconnected and plugged check how smoothly your timing advances as you increase engine rpms. If you raise your engine rpms and hold it at one rpm value the timing should remain steady. As you increase engine rpms the timing should advance smoothly, adding 18-22 deg of advance above idle by the time you get up to 3000-3800rpm..

Thu Oct 03, 2013 3:16 pm

Just take the carburetor off...take it apart...clean everything with carb cleaner...blow out the nooks and crannies with compressed air, paying particular attention to the idle jet....reassemble carefully...give the large bypass screw 2.5 turns out after screwing it all the way in (carefully), and the volume screw three turns out from all the way in ( don't force it in )....that is a ballpark setting to get you running....these carbs have an idle bypass circuit that is extremely sensitive to any dirt or crud that happens to get into it....by blowing out with compressed air, you will actually verify that no dirt is causing your problem...simply adjusting the screws will not always work as you have found out....and your timing just didn't "mysteriously" change all by itself either....you have a carb full of crap....cleaning it is a great start to a sweet running ACVW....P.S....Especially suspect are new carbs right out of the box...take them apart too because there have been instances of metal chips in the passages from the machining process...that happened to me one time.

Thu Oct 03, 2013 5:37 pm

Right, then. Time to start tearing stuff apart!

Thu Oct 03, 2013 6:15 pm

Okay, so I hooked the vacuum retard line back up (I had been running the car with the distributor hooked up like a SVDA instead of a DVDA), reset the timing, and the car actually sounded smoother. However, it still dies at idle most of the time, and the idle wavers back and forth. I've got a feeling it's probably a vacuum leak somewhere.

Thu Oct 03, 2013 9:23 pm

My '72 Super was firing erratically, turns out the 40 year old wiring in the engine bay was at fault. Mine was mainly the condenser wire, but check all those connections, they can't be 100% unless you've already replaced them all. Have you set the valves?

Thu Oct 03, 2013 9:26 pm

I adjusted them a couple weeks ago, only to find they had not changed in 2,000 miles since the last adjustment.

Fri Oct 04, 2013 5:47 pm

Allright. I cleaned up the distributor and the carb, and now my acceleration is back full force. The engine just has some trouble with low idling after pulling off the throttle, but it picks back up. The points plate in the dist. was actually a bit sticky, and after cleaning it, they moved much more smoothly. I also changed out my fuel filter. I am beginning to wonder if my fuel pump is getting ready to go, though.