Distributor questions

[Tom '74 911]

I decided to check my valve adjust from a few months ago because I think I can still hear some valve noise and it seems to be running - not rough, but not silky smooth either. It could be my imagination though too.

I popped off the distr. cap and a piece fell out! Yikes! Here's what I found:



A piece of the rotor had broken off and the metal piece that should be held in place, is what fell out. The broken off bit is nowhere to be found. It either fell out as well when I popped off the cap, or was pulverized. There is a groove carved into the cap where the metal piece was spinning around while not being held in place.

My first question is: what does that metal piece do?

Second, noticed that one of the wires inside of the distributor had been rubbing on the spinning shaft that the rotor sits on. The casing has been worn down and a bit of the wire is now exposed. I pulled on the wire to give it a bit more slack inside - that's why it doesn't look like it would rub in the photo:



My second question is: can I put some elect. tape or liquid tape or something else over the exposed wire and call it good? Also, the PO of my car mentioned he'd converted the "points" to ?something?? Is this where that conversions would have happened? I have no idea what I'm looking at. Could someone give me a brief tutorial?

Thanks a lot,
Tom

[Don Z.]

That thing marked "41T-VA" is where the points would be.

I believe that the piece that broke is part of the rev limiter. When the rotor spins above a certain RPM, that "spring piece" is pushed via centrifugal force and touches the broken piece, grounding out the rotor instead of sending current to the cap.

Can't help you with the wire...

[bob deluke]

Tom, if you can pull the wire through the body of the dizzy, put some heat shrink tubing over it and shrink it down. Looks like a pertronix type setup for taking the place of the points.

[Gunter]

Tom:
Like Bob says: Petronix instead of points, that's good, re-insulate the wire.
While you have the cap off, check the vacuum advance:
Disconnect the vacuum line on the throttle body, suck on it while you watch the upper plate inside the distributor move a little.
Hold the vacuum with the tip of your tongue. Does it hold?
In your picture, the red arrow points to the rubbed wire. Under the wires you can see a round metal cap. Under that cap is a small steel ball.
With a small screwdriver, or toothpick, put a tiny amount of regular bearing grease on the steel ball.
Next to the steel ball housing is a small circlip visible. That's holding the actuator arm for the vacuum pod. Put 2-3 drops of engine oil on top of the circlip.
Also, inside the shaft is a small felt plug. Use a small picking tool and carefully remove the felt plug. Put a few drops of regular engine oil inside the shaft. Replace the felt plug.
Replace the Rev Limiter rotor with a regular rotor and get a new cap.

[Walter_Middie]

Tom,

The Pertronix in my distributor looks the same way - one wire has the insulation rubbed off. I just put a piece of electrical tape on it (but shrink tubing is much better) and I am careful to tuck the wires in when putting the cap back on. It's been this way for years without a single problem.

As Gunter says, use a regular rotor - much cheaper than the rev-limiter rotor.

[Tom '74 911]

Originally posted by Gunter
Tom:
Like Bob says: Petronix instead of points, that's good, re-insulate the wire.
While you have the cap off, check the vacuum advance:
Disconnect the vacuum line on the throttle body, suck on it while you watch the upper plate inside the distributor move a little.
Hold the vacuum with the tip of your tongue. Does it hold?
In your picture, the red arrow points to the rubbed wire. Under the wires you can see a round metal cap. Under that cap is a small steel ball.
With a small screwdriver, or toothpick, put a tiny amount of regular bearing grease on the steel ball.
Next to the steel ball housing is a small circlip visible. That's holding the actuator arm for the vacuum pod. Put 2-3 drops of engine oil on top of the circlip.
Also, inside the shaft is a small felt plug. Use a small picking tool and carefully remove the felt plug. Put a few drops of regular engine oil inside the shaft. Replace the felt plug.
Replace the Rev Limiter rotor with a regular rotor and get a new cap.

Thanks everyone for the responses. I looked up Pertronix in the Pelican catalog and that's exactly what it is. I ordered a new rotor and cap (and decided to treat my car to new plugs and wires and fuel filter too - while I'm in there!). I'll do the distributor maintenance Gunter outlined above too. I'm not sure if the rotor I ordered was the one w/the rev limiter or not. They may have even had the same part number - they do actually ( see here) Is the rev limit function a bad thing? Can I just pop out the metal piece and therefore not use the rev limiter part of the cap? For that matter, could I still use my old rotor w/o the metal piece?

Thanks,
Tom

[bob deluke]

Tom, thats probably o.k. as long as you don't let some bonehead drive your car and overrev the engine and have the valve kiss a piston and bye bye motor. I had a normal rotor in my dizzy and completly rebuilt the distributor and reinstalled the 6500 rpm rev limiter rotor. Not taking any chances with this older 2.7 motor with over 100k on it and a supposedly rebuilt engine(no documentation to support the rebuild). You pays your money and you takes your chances....