72 Early Super Beetle - My new toy

[McDude]

So I just purchased a ’72 and a half Super Beetle. It wasn’t running when I got it, and I had no idea if it would run. A few days of tinkering, and oil change, and a carb (34 Pict-3) rebuild and it started up and even idles (most of the time) despite the fact that I haven’t properly adjusted the idle.

By the way, how can I tell which distributor I have? There is no vacuum advance, so I know it is mechanical which I understand is usually the 009. Based on what I’ve read, the hate for the 009 seems to be universal, but it seems to be working. I guess I need to find a S/N and cross ref it somewhere. I’m also getting conflicting info on whether or not my 72.5 super should have vacuum advance or mechanical. Ideally it would have both, and perhaps that’s where I’ll end up.

I have a strange “rattling” noise. Using a long screwdriver and probing around, it seems to be most noticeable around the crankcase and distributor and I feel a bit of vibration around the base of the distributor. However, it also very noticeable at the top as you can hear in the video. At first I was suspecting worn connecting rod bearings and I haven’t ruled that out, but I wonder if it isn’t something going on in the 009 dist. Some prior owner replaced the points with a CompuFire VW-1 Ignition, and it seems to work well enough, but the mechanical sound at the base of the distributor is unnerving. Video with sounds:


Link

Side Note: I have a single notch pulley. Is that single notch at 5 deg ATDC as I have read? I used that notch as my TDC notch when setting the valves, and that may be part of the problem. Secondly, I was going to check the basic timing (no strobe), and when I went to twist the dist. Housing, it is stuck fast. Of course I loosened the 10mm nut and ensure that the locking ring was loose, but still no twist. What could be going on here?

[youtube][/youtube]

[mukluk]

In your video it seems like the noise is louder when you get near the fan housing, especially so when you poke around on the front near the oil cooler housing. Based on that, I'd lean toward the fan being the source of the noise, either it's rubbing on the housing or possibly the hub nut is loose. You can test this theory by removing the fan belt and running the engine breifly (less than a minute) to see if the noise goes away.

Regarding your distributor, the original would have been a DVDA or dual vacuum, dual advance distributor. It had a combination of centrifugal mechanical advance, and a dual vacuum canister that provided advance and retard depending on engine load.

The crank pulley you have on your engine appears to be the original, or at least the original style. The single timing notch is in fact 5°ATDC. You can use it to set your valves, but your pulley does actually have a TDC marking -- it's the shallow dimple on the top edge of the near lip, less than a finger width to the right of your timing notch.

As for your stuck distributor (which is a 009, btw), if thoroughly loosening the clamp nut/bolt doesn't free it up then it's likely just stuck due to a low quality O ring seal that's turned into the equivalent of glue due to heat and no lube when installed. A bit of persistance and maybe even use of a strap wrench should free it up.
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1960 Ragtop w/Semaphores "Inga"

[Maddel]

[McDude]

Thanks for the helpful tips so far. I confirmed the dimple mukluk mentioned; can't believe I didn't notice it earlier. I was able to free up the stuck distributor and used my test light to set it to the point where it just came on when #1 was at TDC. (I probably should have used 5 deg. ATDC).

I just finished taking super nice video of the bug running without the fan belt. I would show you, but halfway through the import, it lost its mind and destroyed all of the files on the card. Anyway, I'll verbally report what I observed.

1. The noise was the same without the fan belt. The generator spins easily and quietly by hand.
2. Using a long screwdriver again to probe around, I found that the sound was loudest at the base of the generator stand. The sound and feel when listening through the end of a screwdriver is much like the sound of a hammer drill running at low speed if you've ever used one.
3. The sound is most noticeable at low idle, and seems to mostly disappear when revved. I don't yet have the idle correctly set yet, because I haven't acquired the correct tools yet (tach).

[Maddel]

Hmmmm.... Seems like you have a more serious problem then...
For example:
- loosened fly wheel
- crankshaft bearings
- con rod bearings
- piston boss
- valve train
To list a few... But hard to tell from a distance.
The chances are that you have to pull the engine...

[sjbartnik]

[mukluk]

I wouldn't bust out the rebuild kit just yet, there's still another possible culprit for the noise to check in that location: the tin between the crank pulley and case is rubbing/vibrating on the crank pulley.
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1960 Ragtop w/Semaphores "Inga"

[Jomac72]

have to agree with it sounding more like an external contact problem, not an internal engine problem. I would not tear into anything with the motor until I tried finding that a little harder. I like the idea of taking off the belt first...

[jjohnson67]

Pull the belt. See if your noise is gone. Generator needs to be rotated clockwise 90°. In Irving. Where are you in Dallas?

[McDude]

I pulled the belt last night and still had the noise. As mentioned above it reminds me of a hammer drill rather than something that is specific to just a single cylinder. I will try to reproduce the sound and get it into a video to better explain it. It also seems to go away - or at least become less noticeable above idle speeds - even just slightly higher.

@jjohnson67: I'm in Rowlett

Any suggestions on a tool set that would help with timing/idle adj.? Based on the books and forums, it looks like a tach is the best tool for idle, and a basic strobe for timing. Looks like I can pick up a Bosch multi tool that measures tach/dwell as well as VOM for $40 at the local parts house. Anyone use one of those with any success?

[Chochobeef]

There are some good clubs that operate in and around the Dallas area. Maybe try and get in contact with one of them and become a member. They can provide very helpful information and friendship and other stuff.

G.A.S is a big one in Dallas and the others escape me at the moment since I live in Fort Worth.

Wish I could offer more help, but I wish you the best in getting your bug running right.

[iowegian]

[McDude]

I finally pulled the engine last night. Haven't torn into it yet to figure out where the noise is coming from, but hope to get into it this weekend. I will update the thread when I do.

[McDude]

Finally tore it down and had a veteran mech look at it. There were no obvious signs of wear on the mains or cam bearings. When we placed the cam bearing halves back in the case and laid the cam in, he noticed that the cam had significant play back and forth in line with the cam so the diagnosis is "worn cam thrust bearing".

At idle, there is very little load on the cam which allows it to more or less "bounce" back and forth against the thrust bearing creating the internal rattling noise. When revved, the cam loads and is pressed and held against the thrust bearing and stops rattling. At least that's the theory. Won't know for sure until we get it put back together.