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Lucas parts question

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Tinster

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A bit ago, I installed a new Lucas distributor cap
and a new Lucas rotor. I noticed the Lucas rotor
blade cuts grooves into the six aluminum spark plug
wire pickups in the cap. I brush the aluminum
shavings out.

Q? Does electricity arc from rotor to cap pickup?
Or must there be direct contact where the rotor
blade cuts the grooves and makes physical contact.

Just a curiosity question?

thanks,

dale
 
Dale -

How much play does the distributor shaft have? The rotor should not cut into the posts of the cap, and alum. shavings could very possibly be part of the problems you've had.

Mickey
 
:iagree:
Another possibility would be wrong parts, or a bent shaft, or the cap not properly installed. Should be no contact (though very little clearance) between the rotor and posts.
 
Dale, sounds like a bad or improper rotor, (photo please), as a shaft that bad would give some wild point openings and dwell angle and I think all was OK when that was last checked.

Wayne
 
Whatever its cause, there should be no grooves, no shavings.

Think of what's going on inside there as the rotor spins around: There should be, as noted above, a very small space between rotor tip and posts. The spark jumps from tip to post, and then out the wires to the plugs. If there are bits of aluminum flying around in there along with the rotor, there's no telling what's happening to the spark that supposed to travel only from rotor to post. And as I mentioned, it may be the latest culprit.
 
Dale,

There should not be direct contact and assuming that your distributor shaft does not have excess play, it is probably a bad part. I had the exact same problem with a little bit of a twist from a new Lucas cap and rotor.

I replaced the original cap and rotor on my car three years ago. The car and original distributor had 40K original miles at the time, w/ minimal play in the distributor shaft. After 1k miles or so it started to develop an intermittent miss at low rpm and high load, typically at 2nd-3rd upshift. I went through the entire ignition system but couldn't find the problem and the cap looked normal: slight carbon deposits on the rotor tip and contacts. The problem worsened and after much frustration, I finally took a real close look at the cap and it was obvious that the rotor and contacts were making contact. What I thought were traces of carbon were deposits of cap material that the rotor was smearing from around the contacts on to them...basically I had dielectric plastic between the rotor and contacts.

After some other experiences with new Lucas "quality", I replaced the cap, rotor, wires, points, condenser and coil with Bosch and NAPA and use my old original set for the shows.

You are not alone....good luck.
 
Sorry for the photo delay- lunch with the Mrs.

I can detect no wobble in the rotor shaft BUT
the rotor itself does not fit tightly on the shaft.
There is some small amount of play between rotor
and shaft. Although no wobble, I can rotate the
rotor a few degrees, horizontally, with my fingers.

Here's two photos: PS There was no aluminum dust
in the dizzy cap when I installed the new rotor yesterday.

Thanks for the advice: I am attempting a difficult 3 hour
r/t trip, mountain drive tomorrow. Is this dizzy good for
another three hours drive time?

dale

dizzypoints.jpg


newRotor.jpg
 
Dale -

That rotor is trashed! And the cap's no better.

Can you tell what caused the circular groove surrounding the center electrode on the rotor?
 
That's your run problem. Discharge is "tracking" thru the "dust".

One matching cap and rotor from Jeff should be a 50K mile fix.
 
Mickey Richaud said:
Dale -

That rotor is trashed! And the cap's no better.

Can you tell what caused the circular groove surrounding the center electrode on the rotor?
Click to expand...

<span style="color: #990000">Grim News Indeed- I was looking forward to driving
Amos to our Three Kings Day celebration in the mountains, tomorrow.

The circular groove is where the rotor rubs against the top of the cap
where the electricity comes in.

I bought a dizzy cap from Jeff's supplier and it slid out of the
original box broken. But I WILL order A handful of Jeff's new red rotors.

Can anyone tell me what happened in the 65 miles I used that new rotor?

thanks!! At least I did not break down on the highway.

d</span>
 
<span style="color: #FF0000"><span style="font-size: 20pt">One matching cap and rotor from Jeff should be a 50K mile fix.</span></span>
 
Dale, it looks like there's either too much slop in the shaft, or the rotor isn't fitting properly, allowing it to travel where it will.

The rotor should fit the shaft quite tightly ("Mellow Yellow"!), and should not rub against the cap anywhere but the central electrode of the cap, which is supposed to be spring loaded.
 
From a couple thousand miles away, I can't be certain of anything -- BUT -- from the look of those parts, One (or both) of them is simply the wrong part. The clearances are wrong, wrong, wrong, and they've beaten each other to bits!

I don't mean to send you into a paranoiac tailspin, but it does happen -- even to the experienced guys. It's not an epidemic, but wrong parts DO get delivered, sometimes even in the "right" box.

You need a new cap & rotor. Those two aren't going to make it to Three Kings Day and back. I've heard you have a boot-full of spare ignition components. Look there?

And -- What the other guys have said is true: A new set from Jeff will be a 50K mile fix.
 
That is NOT a lucas rotor. Even if it came in a Lucas box. It is slightly too large, and hits the cap electrodes, as well as the top of the cap. As aluminum is condutive, the "dust" is creating unwanted paths for the high voltage electricity to travel around inside your distributor. Electricity always takes the path of least resistance, and it is easier to go to ground inside the cap than it is to jump the gap at the plugs. This creates "Missing", and if bad enough, stopping. The rotor should fit tightly on the dizzy shaft with no "lost motion". The advance mechanism in the dizzy should let it rotate a bit, along with the "points cam" that you can see.
 
DrEntropy said:
<span style="color: #FF0000"><span style="font-size: 20pt">One matching cap and rotor from Jeff should be a 50K mile fix.</span></span>
Click to expand...
:iagree: ...although I suppose one could justify having <span style="font-weight: bold">a</span> spare QUALITY rotor just in case you drop one and it rolls down into a storm drain, or.... :wink:
 
Thanks Jesse,

Now, I would really, really like to drive this car to
Three Kings Day tomorrow.

Yes, I have a spare dizzy cap but my spare rotors were
sourced at the same time, from the same place. Since the
dizzy cap was not eaten prior to the new rotors, the problem
logically is the rotor.

I have a new cap and the original Lucas rotor that was in
the dizzy when we bought the car. The rotor was functional
when I removed it to have the dizzy rebuilt.

Here is a photo of the Lucas rotor that I have on hand.
If I install this oldie rotor and my new dizzy cap- will
the car be able to make a hard, 3 hour drive??

OR is there a possibilty Western Auto or Auto Zone might
carry a rotor for my Lucas dizzy?

thanks,

dale

spareRotor.jpg
 
Tinster said:
...If I install this oldie rotor and my new dizzy cap- will the car be able to make a hard, 3 hour drive??
Click to expand...
(Disclaimer: I can't see the photos here at work.) Dale, if the rotor fits snugly on the distributor shaft, then I'll guess it would be just fine!
 
Update:

I installed the new dizzy cap and the ancient old
Lucas rotor. The engine fired up instantly and I
let it run at about 2500 rpm for a few minutes.
The engine seemed to run very nice.

I stopped the engine and took the new dizzy cap off
to inspect the insides. No metal dust of any kind,
the rotor edge looked no different and there were no
grooves cut into the new cap electrode points.

Should I risk a difficult 3 hour drive with no
spare rotor?

Edit: I took the car out for a 20 minute ride and it
ran good up to 60 mph. I think I'll rish the 3 hour
drive tomorrow. A whole bunch of folks would be
disappointed if Amos is a "no show" for Three Kings Day.

And I'll be driving with no spare rotor!! YeeGADS!!
Dale with no spare!!

thanks,

dale
 
Should be fine. Bring the "cra...um, not-so- good ones just in case. The rule of thumb is that if you bring something as a spare, you will never need it. So, be prepared. The old rotor looks OK, but without having it in hand, hard to be sure. They are pretty simple parts though, and having the correct set should solve all the issues. Happy motoring!!
 
:iagree:

Yep, and just for your own peace of mind, you can try out the spares you're going to bring with you to be sure they're OK.

Mickey
 
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