Breaking rotors

[NK Nance]

You've heard my story before where i blew something but can't figure out what. So I purchased plugs, points, cap, rotor, condenser thinking maybe this is why my F1 will not start. I now have broken two rotors which interfer with the cap contacts. The parts store tell me they are correct. The rotors look exact and the cap looks correct on the outside however the inside is a little different. After the first breakage I purchased another thinking maybe I did not seat the rotor properly. This was not the case. Has anyone experienced this? The parts store has no clue as to why. Thanks in advance for sharing your experence. I really want to get the old ford on the road as it has always ran great in try past. This all started when I connected the charger to the wrong post as I was looking at the cable color and not the battery post. Forgot it was a positive ground.
Thanks again for any and all ideas
Norman in Green Bay

[37don]

Many of the after market caps are not concentric. The mounting surface is not concentric with the mounting lip.I had to file a little off the rotor several yrs ago so it would clear the contacts. I have a Mallory cap right now and appears to be a good quality cap with a built in rubber seal where it contacts the distributor. I would try any new cap on a spare dist.before I install it on the car.
Don

[Lanny]

Have you checked for a bent shaft or bushing out, allowing the shaft to wiggle around a little bit.










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[NK Nance]

Thanks Don. Good advise. Will need to get another distributor

[NK Nance]

It worked fine before so I am assuming it no bent shaft to cause this problem

[ford38v8]

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On the other extreme of the clearance issue is the rotor that is too far away from the contacts on the cap, which would tend to encourage carbon tracks and crossfires. The fix for this condition is to solder the tips of the contacts, to be cut by the rotor.

[Terry,OH]

I had the same problem with crab using NAPA cap and rotor. I went to NOS cap and NAPA rotor, sent the distributor to Bubba he found the point plate bent, replaced the point plate. This would also throw the snap ring off. All is fine now, so I am not sure if it was the bent point plate or the two NAPA caps. Rotor would hit just one terminal of the cap.

[Barry WNY]

I have a new Mac's cap that broke 2 rotors. Foreign junk, running the old used one with new rotor. Someone must have a tool to recut these half !ss parts.

[NK Nance]

Who is Bubba?

[Binx]

BUBBAS IGNITION is his user name. He runs a distributor rebuild shop in Indianapolis near the speedway. He's one of a few ignition go-to guys here. Look at the search feature then click on advanced search and type his user name in to see his posts. He's quite an artist with these relics with loads of knowledge. PM him with your concern. While you're here, take the time to back-page through all the archives here and learn the answers to nearly all your questions you may have -- now or in the future. Quite lengthy, but a wealth of information.

Lonnie

[NK Nance]

Thanks Lonnie

[4dFord/SC]

Originally Posted by NK Nance

Who is Bubba?

http://www.lindertech.com/bhrs/services.htm (Google is your friend)

[TomT/Williamsburg]

About a year or so ago I needed new cap and rotor for my Pertronix converted 8BA distributor - I went to Napa and bought them but promptly broke 2 rotors. Bought them with another supplier on line for both the cap and rotor and no problems since.

Problem was the caps would not "seat" right or stay seated properly - the rotors would also not seat properly. A combination of the two problems caused the rotors to break. I did bring this to the attention of the local NAPA store, demonstrating the problem with a distributor. They were going to look into it and/or notify whomever - I've not had any word back but they did refund my money.

[Mart]

After your experience, I'd be tempted to try any new parts with the distributor removed from the engine. Turning it by hand you should be able to feel any interference between the parts. You should also be able to really see if the parts are fitting properly.

Mart.

[G.M.]

Take the wires, cap and distributor off. You can put one cap on at a time and look in and see the problem. G.M.

[BUBBAS IGNITION]

As per our phone conversation this morning , i think you are dealing with a couple isses.
The number one issue is that these need a rotor retension clip.
Reinstall this clip ( may need to bow the tang section to make a tight fit).



Secondly i would take , grind just a small amount off the rotor tip ( i do this on most aftermarket rotors). Sometime the clearances are just too close . The increased clearance wont hurt anything and may even make it have a little better spark with the increased gap...

[JM 35 Sedan]

Good advice from Mart (over there ) and also from the guys who are recommending Bubbas Hot Rod Shop (Linder Technical Services). He and his folks do excellent work on all of the Early Ford Flathead V8 distributors. He did such a nice e job rebuilding a crab distributor for me that I just sent him another to carry in one of my cars as a spare. Can't say enough good things about the man and the quality of his work.

[55 dude]

Fair prices and outstanding customer service! hard to find someone that is excited about doing quality work and standing behind it.

[PeteVS]

You have to make double absolute sure that the rotor is FULLY seated on the shaft. Sometimes, new rotors can be a little tight where they go on.

[49r]

My 'Made in Mexico' 8BA cap from Macs has been on one year - so far so good ...