I have a 92 Caprice with 305 engine and I have a very strange problem.
It seems that the rotor tip is lightly hitting the contacts on the
distributer cap causing gouging of the contacts. It happens on ALL the
contacts but is worse on some.
Obviously my first thought was play in the distributer shaft because this
particular distributer has more than 300,000 miles on it. The first was
replaced by the dealer at about 40,000 miles due to a factory bulletin.
However, there is not even the slightest amount of play on the shaft and
the rotor and cap are seated properly.
I don't think the shaft is bent because that would show up as hitting on
One last question, I am going to replace the distributer anyway but there
does not seem to be that much clearence between the cowel and the top of
FSM says remove the bolt and pull it out.
Anyone do this in a Caprice?
Are you sure that what you are seeing is the rotor "gouging" the cap
contacts? Every cap that I've ever seen with some miles on it, will
have indents in the contact area....this is normal wear from the spark.
Same thing happens with spark plugs, the metal electrode gets worn.
Time for a new cap and rotor if this is all that is happening.
On Sun, 22 Aug 2004 22:00:14 +0000, shiden_Kai wrote:
It's happening with a new cap and rotor and I even went out and got a
different brand cap and rotor to make certain.
Also if you put your hand on top of the cap while the car is running, you
can actually feel it.
Just out of curiosity when did you first notice this phenomenon and what
brought it to your attention? Can you point to a particular time frame
before which there was no problem and after which there was? What if
anything was being done to your machine during this time frame?
On Mon, 23 Aug 2004 01:04:57 +0000, Silver Surfer wrote:
I just replaced the cap and rotor today with the same brand I have always
When I started the car I heard whatt sounded like a ticking valve, or an
injector making noise.
I put my hand on the cap and I could feel a slight knock which
corrosponded to the noise.
I turned off the engine, removed the cap and rotor and sure enough I could
see a very, very light scape mark on the caps electrodes. A little more on
one side of the cap than the other.
Thinking I didn't have the rotor/cap seated I tried again with same
Just for kicks I tried a different brand cap and rotor I had laying around
and had the same thing.
If I put my hand on top of the cap and gently flexed it to one side or the
other (you can barely feel it move at all), witht he car running I could
make the sound change.
I took a look at the old cap and the electrodes had deep grooves in them,
yet I don't recall hearing any sound.
Hmmm.... That's odd...
Turns out, I play with the wires on the cap, just twisting them a little
while the car is running and the SOUND GOES AWAY!!!
Possible arcing noise due to positioning of the wires?
Even if so, why the mark which to me looks like a slight scrape not the
It's all very strange but I think it is fixed.
This might just be normal wear in the distributor ... I think you said it
had 350K on it. Try moving the shaft up & down in the dist housing, there
shouldn't be much slop. The contacts in the old cap may have been worn down
slowly over time & the interference is only now showing up with the new cap.
This 'may' affect your engines' timing. Get a replacement dist at the
wreckers with less miles, check the part number in the casting & get the
Went back and reread your original post. It's hard for me to envision how a
distributor shaft could get bent, but would that not cause the problem you
are experiencing (or were experiencing)? If the shaft is bent the end of
the rotor would have a slight orbit and likely contact all of the high
voltage contacts inside the cap. You should also see a circular wear patter
on the rotor button as well assuming that it has had enough action to show
On Tue, 24 Aug 2004 00:26:18 +0000, Silver Surfer wrote:
Yea, that's what had me confused as well. In addition, if the thing was
hitting, even on the old cap and rotor, it would have destroyed itself in
I finally found the problem and it was indeed arcing of the wires.
I ran the car last night with the hood open and sprayed a mist of water on
the cap, the new cap, and I could clearly see arcing between some wires.
I replaced the wires and all is well.
I gues the *marks* on the inside of the new caps electrodes were just
normal, although they sure as hell looked like physical contact had been
made to me!
Bottom line, wires fixed the problem.
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