Bad distributor?

[Mr Blotto]

Howdy Volks,

I recently noticed kind of a snap/crackle/pop sound at idle coming from the distributor area at idle. I popped the cap off and discovered that the distributor shaft has both rotational and vertical free play. How much free play is acceptable? It seems to be running fine...but this noise ain't kosher. I have 109k miles on what I think is the original distributor. Or, is this a sign of trouble in my engine's netheregions?

[ruckman101]

I don't think up and down play is all that critical, but side play is. I remember I had to replace mine in my '80 Jetta. Don't remember any noise, just really bad idle. But the side play should be snug.


neal

[Mr Blotto]

Hmmm.....I did not check side-to-side play, just rotational and up/down. I will have another look when I get home tonight. I just don't know when this noise started. You can't hear it with the engine lid down, and it seems to be running fine.

Thanks

[yondermtn]

My distributor was very loose and the two "teeth" weren't catching and turning with the engine. I took it out and to me it seemed like too much play. I put in a spare I had and that seemed to work. Here's a pic of the play I had in my old distributor.

[Amskeptic]

Hmmm.....I did not check side-to-side play, just rotational and up/down. I will have another look when I get home tonight. I just don't know when this noise started. You can't hear it with the engine lid down, and it seems to be running fine.

Thanks

Check for the spring in the middle of the drive shaft down the hole with the distributor out. The vertical play is fine as long as that spring is accounted for. There are thrust washers between the distributor's drive dog and the distributor body. One of them used to be a fiber washer that often gets broken and falls out.

The brass drive gear on the crankshaft can get mangled all too easily if you:
a) don't have the spring down the hole
b) rotate the engine backwards, especially when the flywheel is off

Look for any evidence of hits between the rotor and the distributor cap.
Colin

[Mr Blotto]

Thanks fellas
*Gulp* - I have never removed my distributer. First time for everything I guess.....

[ruckman101]

Put it at TDC on #1 and take it out with the clamp still on it. Keeps your timing. Then you can pop it right back on. I pull my distributor to set my points gap. Piece of cake.

neal

[Mr Blotto]

OK - time for a stupid question........

How does one fit a wrench or socket on that 13mm nuts that loosens the distributor hold down clamp? Do I need an offset wrench?

[ruckman101]

I've only dealt with type 1 engines.

neal

[Amskeptic]

OK - time for a stupid question........

How does one fit a wrench or socket on that 13mm nuts that loosens the distributor hold down clamp? Do I need an offset wrench?

I have used a small 13mm box wrench coming in from slightly under the cold start valve. You can unplug the cold start valve plug for better access.

Or you can loosen the 10mm clamp bolt (score the position of the distributor against the clamp, first) and just rotate the distributor to a more advantageous position.
Colin

[Mr Blotto]

Thanks Colin - i will give it a try. Here is a short video of my freeplay. (First time trying to post a vid!)
http://youtu.be/y1GVBi5NVcg

Does this seem normal?
Thanks guys!

[ruckman101]

Isn't that just the mechanical advance? It is on mine. Springs with counterweights underneath. Mine does that on the Ghia. Vacuum only advance on the single port engine I just got into Bertha Bus. And yes, that seems normal.


neal

[Mr Blotto]

Thanks Neal. Perhaps I need to get a stethoscope and pinpoint where this noise is exactly coming from before I go ripping stuff out.

[ruckman101]

The inside of the distributor cap is clean? Could it be arcing?

neal

[Mr Blotto]

The cap and rotor had a little carbon deposits, but nothing that seemed abnormal. I did notice that the area below the rotor (where the points are) was a bit dirty and oily, but it seemed to be residue from oiling the wick and lubing the shaft where the points hit it?? I do not have a dust cover installed....