66 Beetle, Backfiring out of Carb on Acceleration

Beetle, Karmann Ghia, Thing.

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wdollie6
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Re: 66 Beetle, Backfiring out of Carb on Acceleration

Post by wdollie6 » Tue Sep 06, 2022 6:47 am

Received new light switch and installed but unfortunately it was missing the terminal 57 connection so had to move the parking lights to the light circuit which seems to work fine, although they are now on all the time. Switch made a big difference along with a few other changes that I made; thoroughly cleaned ground strap at battery and transmission, replaced regulator and brushes from old generator that was on one of the two engines I purchased last year for $50 (good investment so far although my significant other begs to differ).

Bug is now running great, with a voltage gain of 0.5 volts at most places in the electrical system. The headlights are much brighter and the wipers run like they are on 12 volt, nice. Unfortunately have now developed a low siren noise that will last a 8-10 seconds but then fades. I'm thinking this is either the pilot or throw out bearing, so will have to pull the engine to take a look, unfortunately I can't really pinpoint at this time.
1972 Superbeetle Convertible
1972 Westy Bus
1972 Beetle
1970 Fastback
1966 6V Beetle with Sunroof

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wdollie6
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Re: 66 Beetle, Backfiring out of Carb on Acceleration

Post by wdollie6 » Tue May 30, 2023 4:06 pm

A few weeks ago pulled the 66 out of storage, checked oil, charged battery and she started up. Unfortunately after a few short road trips the generator light came on and this time it was constant. Checked the regulator and found it wasn't producing any voltage above battery voltage, which led me to believe that I had a generator issue as well.

Since I had other issues to deal with (main seal, transmission seal, etc..), I pulled the engine and was happy that I did so as the flywheel and the clutch were deeply grooved and worn beyond repair. Fortunately I had an old 6 volt engine that I was able to use the flywheel, clutch and clutch plate off from. The only difference was that it was from a '64 which didn't have the o-ring seal at the flywheel but rather used a thin small, 4 hole, washer. I was also able to use the shims from the '64, end play was at .004, as the ID of the shim was different as well.

I ordered a generator from Rock Auto, and a regulator from NAPA (although I still have my Bosch which I may reinsert at some point). I didn't have a lot of confidence in the generator but it is a Bosch rebuild and so far the combination has worked fine. The bug is reassembled and it is working great again, all leaks are gone, with the exception of one small leak at the passenger side valve cover. At the same time I also changed out the boot on the axles so those are leak free as well.

Went for a long ride today and everything worked great with the exception of a clunking noise on the passenger side when re-accelerating in 4th gear. Checked lugs and main nut on that side all is tight. Next will be body mounts, shocks, etc.. Definitely not an engine or transmission noise, will update when I find the cause.
1972 Superbeetle Convertible
1972 Westy Bus
1972 Beetle
1970 Fastback
1966 6V Beetle with Sunroof

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Amskeptic
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Re: 66 Beetle, Backfiring out of Carb on Acceleration

Post by Amskeptic » Fri Aug 04, 2023 9:49 am

wdollie6 wrote:
Tue May 30, 2023 4:06 pm
The bug is reassembled and it is working great again,
clunking noise on the passenger side when re-accelerating in 4th gear.
Definitely not an engine or transmission noise, will update when I find the cause.
Update? I need to drive that car again ... it has been four years.
(I have 62,000 miles on the cylinder heads we installed at your place)
Colin
BobD - 78 Bus . . . . . . . . .115,063 miles
Chloe - 70 bus . . . . . . . . 219,045 miles
Naranja - 77 Westy . . . . . 185,060 miles
Pluck - 1973 Squareback . . 55,630 miles
Alexus - 91 Lexus LS400 . . 99,705 miles

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