bent rotor contact blade

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rigger3006

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so i changed to an aluminum rad and new carb gasket, 360 fired right up, when i kicked the choke off the idle would surge, then engine would die.would not start after.troubleshooting i found a twisted contact blade on rotor under distributor cap, replaced it, still wont fire.this has happened three times over the past five years. any thoughts how this is happening?
 
so i changed to an aluminum rad and new carb gasket, 360 fired right up, when i kicked the choke off the idle would surge, then engine would die.would not start after.troubleshooting i found a twisted contact blade on rotor under distributor cap, replaced it, still wont fire.this has happened three times over the past five years. any thoughts how this is happening?
First thing is pull distributor, and see whats worn out. Has to be something. Or a bent shaft. No point speculating, dist has to come out. If i was in the states, i would box it up and send it off to halifaxhops. he knows his stuff. He may have a drop in, ready to go.
 
i tried dropping in a different distributor, but im not sure if its a good one or not, ive had it in a box for a couple of years, im just wondering why it wont fire, then i will be buying an all new distributor
 
i tried dropping in a different distributor, but im not sure if its a good one or not, ive had it in a box for a couple of years, im just wondering why it wont fire, then i will be buying an all new distributor


Did something bend the blade on the rotor, or did the rotor fail and let the blade rotate? I had a Mallory rotor fail because the little screw holding the blade to the rotor came loose and the blade spun around and the engine quit. Luckily, I was only a mile and a half from the shop so I towed it back.

What a PITA because I thought I broke something in a brand new engine.
 
i tried dropping in a different distributor, but im not sure if its a good one or not, ive had it in a box for a couple of years, im just wondering why it wont fire, then i will be buying an all new distributor

Take the harness side of the distributor plug and with the key on in the run position tap the exposed metal bullet to ground. (intake, block, whatever)
You should get one spark with each touch.

Of course this assumes you have the stock ignition module.
If it sparks you know the module is working.
 
If you mean the blade attached to the rotor that rides on the coil contact inside the distributor cap; wow, never heard of that happening.

To start, I think you need to replace the cap, rotor and condenser with high quality parts and go from there. Is there evidence of the rotor tip coming in contact with the distributor contacts?

There is about a 4 page long article at slantsix.org where a guy tested and measured various combinations of rotors and caps. He didn't look at just one cap/rotor combination but checked multiple parts from the same manufacturer sourced from all across the states. He actually cut windows in caps and measured running clearances etc. What I mostly took from that article was there is a lot of bad parts out there and used the info to choose parts when I rebuilt my slant.
 
Sure, it's pretty common. The distributor has a plastic collar on the shaft attached with a roll pin. This keeps the shaft in place vertically. If the plastic holes in the collar get worn or broken, it can cause slop and the shaft can go up in the distributor housing and the rotor will smack into the inside top of the cap.
 
it looks like it slowly developed judging by black soot on top of rotor, its a standard brand,same brand as happened before,thanks for tip on testing didtributor
 
Take the harness side of the distributor plug and with the key on in the run position tap the exposed metal bullet to ground. (intake, block, whatever)
You should get one spark with each touch.

Of course this assumes you have the stock ignition module.
If it sparks you know the module is working.
yes im using the chrome box, as per your test, no spark, i have 2 old ecu's floating around, do i have to mount and ground them for the same test procedure?
 
yes im using the chrome box, as per your test, no spark, i have 2 old ecu's floating around, do i have to mount and ground them for the same test procedure?

Then it looks like your ecu might have gone (as long as power is getting to it)
Yes, they HAVE to have a good ground.
In fact you might clean the contact surfaces on your chrome box and test it again.
Some put those star type washers between the box and it's mounting surface to be sure of a good ground.
 
Then it looks like your ecu might have gone (as long as power is getting to it)
Yes, they HAVE to have a good ground.
In fact you might clean the contact surfaces on your chrome box and test it again.
Some put those star type washers between the box and it's mounting surface to be sure of a good ground.
yes im using the star type washer, im very ignorant of using my tester, not sure what setting to put it on, on 12v battery load,i have lots of voltage at #1 pin, but hardly anything on 2 pt harness that hooks to didtributor
 
yes im using the star type washer, im very ignorant of using my tester, not sure what setting to put it on, on 12v battery load,i have lots of voltage at #1 pin, but hardly anything on 2 pt harness that hooks to didtributor

That's ok.
As long as you see some power at the ECU continue the test with the other ECU.
Meter to 12v DC for voltage testing on cars. (or DC volts on some)
 
first off, thanks guys for all your sage advice,secondly,bang head repeatedly!!!! and fix fuel gauge and stop turning wrenches after 6 beers!talk about winning the dumbass of the year award,out of goddamn fuel!LOL still have the bent rotor blade dilemna, very little vertical play on didtributor shaft,i think i'll buy anew one
 
Lets not forget a but of rust on shaft, and rotor doesent go all the way down. Easy to overlook.
 
Not sure if this helps or has much to do with your rotor issue but I had a roll pin come loose on a reluctor wheel. This caused the wheel to spin some on the distributor shaft. Made it skip terribly and had me pulling my hair out.
 
Here is something not mentioned. If cap gets bumped and tilted, it will cause rotor tab to hit a terminal. Things like tight clearance to firewall, loose motor or trans mount.
 
so i changed to an aluminum rad and new carb gasket, 360 fired right up, when i kicked the choke off the idle would surge, then engine would die.would not start after.troubleshooting i found a twisted contact blade on rotor under distributor cap, replaced it, still wont fire.this has happened three times over the past five years. any thoughts how this is happening?
Bent upper shaft prob the bushings are toast!
 
Not sure if this helps or has much to do with your rotor issue but I had a roll pin come loose on a reluctor wheel. This caused the wheel to spin some on the distributor shaft. Made it skip terribly and had me pulling my hair out.
That's called Phasing if it helpes
 
That's called Phasing if it helpes
hmmmm.... so i walked away from it for a day, just fired it up, warmed up fine, vac gauge was steady at 17 at 1000rpm, went to get timing light and it started surging again.1000 down to 200,it repeated this for about a minute and a half then stalled out, checked rotor again, not bent,all cylinders at proper temps per heat gun,voltage regulator warmish, ballast resistor warm,once i and the car cool down i will check the reluctor pin
 
reluctor and pin seem normal.when i grab rotor and twist it i get at least 1/4'' movement, maybe a tad more, normal? this is the only distributor ive ever had in the car, except for a crappy firecore, so i dont really know how much play there should be
 
Yeah that is normal movement. Mine was doing similar stuff. Reluctor gap good? Watch how reluctor meets up with each tooth. Take it out of engine to check.
 
That twist is the advance. It should return nicely. The distributor turns once for two engine revolutions. The circumference of cap id is about 9" (guess ), 1/4 divided by 9 times 720 degrees is about 20 degrees, that is close to typical mechanical advance.
 
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