Deystroyed distributor rotor !

[cpaq]

So, sure could use some help!
413 engine quit running on highway…no spark, no start. Orange box ECU from Mancini. Power and continuity through resistor , coil resistance ok, power at orange box…tried three boxes , still no spark. Took the distributor cap off, rotor is destroyed! Has anyone ever seen anything like this? What could have caused this to happen under the cap? Would really appreciate feedback THANKS!!

 

[pnora]

Rotor has been damaged most likely taking the cap on and off.

 

[cpaq]

Rotor has been damaged most likely taking the cap on and off.

Today was the first time I have taken the cap off since installation !

 

[pnora]

Today was the first time I have taken the cap off since installation !

Right. But the rotors cap contact was bent/twisted when the cap was last put back on. They can run but eventually self destruct as seen by your photo.

 

[Sam69sat]

How much play is there if you pull up on the distributor shaft? Maybe the retainer bushing broke and your getting vertical play on the shaft.

 

[pnora]

Also it could be possible the rotor was never fully seated. It would be up to high.

 

[cpaq]

Right. But the rotors cap contact was bent/twisted when the cap was last put back on. They can run but eventually self destruct as seen by your photo.

Today was the first time I have taken the cap off since installation !

Could be…something real bad happened under that cap that’s for sure…hopefully the distributor wasn’t damaged when the thing self destructed. Almost looks burned . Have u ever seen anything like this? THANKS!!!

 

[Lefty71]

Looks like there's been some heat in the there too... look at the pickup coil against the case... Also, I see that lot of turds in the motor.... better start looking for damaged chewed wiring too.

 

[cpaq]

Could be…something real bad happened under that cap that’s for sure…hopefully the distributor wasn’t damaged when the thing self destructed. Almost looks burned . Have u ever seen anything like this? THANKS!!!

New rotor, engine fired right up…weird …I’ll see if any vertical move on dist shaft, a good idea. The car was at the end of a 300 mile trip and has run great for years so I’m assuming the rotor was seated properly …really odd not what i expected to see when I lifted the cap

 

[Sam69sat]

 

[Charles Cook]

vertical play on the shaft.

This is usually a good thing. Never seen that before unless the coil fried it. Not sure

 

[RJRENTON]

So, sure could use some help!
413 engine quit running on highway…no spark, no start. Orange box ECU from Mancini. Power and continuity through resistor , coil resistance ok, power at orange box…tried three boxes , still no spark. Took the distributor cap off, rotor is destroyed! Has anyone ever seen anything like this? What could have caused this to happen under the cap? Would really appreciate feedback THANKS!!

View attachment 1339341

View attachment 1339342

View attachment 1339343

The second pix says it all.....the rotor failed because (IMO) due to insulation break down from the spring loaded wiper arm to the end of the rotor to the end contact. This is typical of inadequate dielectric strength of the rotor to and thru the rotor material to the shaft. GM had a similar issue shortly after the HEI ignition systems was introduced......they changed the rotor material to a fiberglass reinforced alkyli material. This type of failure usually occurs over time and us fue a combination of heat and high voltage breakdown. Is bakelite better (black material) better?? Once the insulation is compromised, failure is imminate. The search for higher and higher spark voltage (in the never ending quest for more HP) has its limitations unless the down stream components are able to withstand the high voltage. Ozone is generated by the arcing and ozone can be corrosive and causing rusting of metal parts. Just my opinion of course......
BOB RENTON

 

[cpaq]

Looks like there's been some heat in the there too... look at the pickup coil against the case... Also, I see that lot of turds in the motor.... better start looking for damaged chewed wiring too.

The second pix says it all.....the rotor failed because (IMO) due to insulation break down from the spring loaded wiper arm to the end of the rotor to the end contact. This is typical of inadequate dielectric strength of the rotor to and thru the rotor material to the shaft. GM had a similar issue shortly after the HEI ignition systems was introduced......they changed the rotor material to a fiberglass reinforced alkyli material. This type of failure usually occurs over time and us fue a combination of heat and high voltage breakdown. Is bakelite better (black material) better?? Once the insulation is compromised, failure is imminate. The search for higher and higher spark voltage (in the never ending quest for more HP) has its limitations unless the down stream components are able to withstand the high voltage. Ozone is generated by the arcing and ozone can be corrosive and causing rusting of metal parts. Just my opinion of course......
BOB RENTON

Tnx bob

 

[RussT Plymouths]

It looks like the rotor's flat metal spring is stuck to the magnet on the pickup coil. What does it look like? I'm wondering if it didn't crack through the rivet hole and just fall off. I've tossed more than a couple rotors that had a crack starting to develop across the spring. Also had one where the rivet came loose and everything fell out. I know what I found were non OEM parts, but who always knows what we get.

 

[dual fours]

Is this a missing metal rotor contact?

EDIT: Ok, I see I'm slow. It's already been picked up on.

 

[pnora]

Is this a missing metal rotor contact?
View attachment 1339396
Ok, I see I'm slow. It's already been picked up on.

That looks nicely bent and twisted. You can see its burnt bent image made into the rotor in the other pic..

 

[dual fours]

One reason I carry an extra Dist. cap. just in case something cracks a piece out of the cap.

 

[PlymCrazy]

When the spring contact of the rotor gets compromised(bent, oxidized, or in this case missing) arcing becomes greater and greater essentially like a welder on high power on a thin piece of metal. As that material becomes less and less the arc has to jump further to reach the end of the rotor and the heat inside the distributor cap gets greater when exposed to the greater arc (as evidenced by the melted plastic in the pic).

Had this phenomenon happen one time on one of my trucks. Threw in a used rotor from a spare parts box I had. That rotor spring got pushed nearly flat by some other parts in the box. I ignored it and installed it anyway. Literally the same exact thing happened as what is seen here.

I’d check the cap button for integrity as well, if you haven’t already.

 

[cpaq]

Unbelievabe!

 

[cpaq]

It looks like the rotor's flat metal spring is stuck to the magnet on the pickup coil. What does it look like? I'm wondering if it didn't crack through the rivet hole and just fall off. I've tossed more than a couple rotors that had a crack starting to develop across the spring. Also had one where the rivet came loose and everything fell out. I know what I found were non OEM parts, but who always knows what we get.

Ruh roh….u may be right….I’m on it…it had to go somewhere!!