1934 Ford model 40 Distributor

[Richard Delahay]

Hi Ford Barners, I have difficulty in obtaining a distributor rotor and inner terminal caps that do not leak high tension voltage. NOS rotors leak volts to the central steel spindle "straight out of the box."
Does anyone know of a source of rotor (32-15181-1) and inner terminal caps
(32-11938-1) that are manufactured from modern insulating material ?

[koates]

Maybe you could explain exactly what your ignition system consists of. Is it all original 6 volt 1934 Ford or some other modified system. Are you using the original coil with the under dash ballast resistor. A good NOS rotor and caps should not leak on a standard system. Some guys tape or insulate the shaft under the rotor but I find that not to be normally necessary. What spark plug gap have you set ? Should be .025" . Any change away from the original ignition system could potentially increase the high tension voltage and cause your type of problem. Regards, Kevin.

[DavidG]

The numbers that are cited are not the Ford part numbers for the rotor or inner caps, which are 18-12201 and 18-12116, respectively.

[deuce lover]

They appear to be Mac's numbers.

[JSeery]

Yep, looks like it. Might check with Bubba for suggested parts source. http://www.bubbasignition.com/helmet--32-41-1.html

[BUBBAS IGNITION]

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How are you testing for this leakage???

[Richard Delahay]

Ford Barners, many thanks for your interest in my ignit ion problem.
History;
Stock 6 volt ignition worked after restoration with new rotor and capacitor. Ballast resistor in place.
Then coil failed after 3 months.
New coil (dome top) from major supplier in USA fitted.
This new coil failed after few weeks.
Supplier not interested in conversation.Uneconomic to ship failed coil to USA.
Remote 6 volt coil fitted, OK when cold, severe missing when hot. Removed ballast resistor solved missing problem and car ran OK for 10 years.......
......then missing returned when engine warmed up.

DiagnostIc effort resulted in new parts being fitted and tried out one at a time without solving problem. Parts were: plugs, all HT leads, remote coil, points, capacitor and rotor.
At this stage engine would idle OK, but ran rough when hot.
I then tested a new purchase rotor (believed NOS) by leaving ignition configuration as above and added a second HT lead to coil output in parallel to the stock lead. Second HT lead connected to the second NOS rotor brass slip ring. Second NOS rotor mounted on a screwdriver steel shank. Engine idling and screwdriver tip brought near cast iron engine head. Engine continues to idle OK and sparks regularly occur between tip of screwdriver and engine head ! Ergo leaky rotor demonstrated.

(Rotor supplier in UK not interested in this discussion)
Next move, fit a 1942 crab type distributor with new points, rotor, cap and capacitor. Result, perfect performance for 12 months and still OK today.
Good result believed to be due to better insulation material available for crab type parts. Note, new rotor for 1942 distributor passes the screwdriver test!!!

So my search for 1934 parts is to enable a return to original configuration. Meanwhile car (model 40 fordor) been in the same family since 1945, is running OK.

[Mike in AZ]

Welcome to the ‘Barn. Hopefully you can get your questions answered. And post pics if you can. Mike

[JSeery]

Might in interesting to post what coils (tin can style) you are using. The ohm value makes a difference. On the original coil, your best bet would be to have it rebuilt.

[koates]

Originally Posted by JSeery

Might in interesting to post what coils (tin can style) you are using. The ohm value makes a difference. On the original coil, your best bet would be to have it rebuilt.

Yes I agree with the above. Do a voltage test at the coil ignition supply terminal with engine running. The canister coil requires 6 to 7 volts which means the ballast resistor is not used, but would depend on the primary winding ohms resistance of that coil. The original Ford bakelite coil on the helmet distributer requires 4.5 volts with the ballast resister in series with the ignition supply. Don't buy todays new reproduction caps or rotors but buy NOS genuine Ford OR older NOS replacement parts which were made in the 1950s or so by many different aftermarket companies. These parts come up on ebay quite often. Also use a genuine Ford original ballast resistor, NOT a reproduction. THE original Ford ignition helmet distributer components on your 34 Ford were very very good in design and operation. I have them all on my 34 original four door sedan and never a problem. So get back to the stock system. Regards, Kevin.

[rotorwrench]

The type and composition of high tension leads can also have an affect. I assume you are from somewhere else in the world, UK, Down Under, etc. where finding parts may be more difficult. There are several rebuilders of OEM coils here in the states and most folks have their originals rebuild with modern materials to solve many of their problems. There are good and bad ignition system components for sale out there too so a person has to purchase the best parts available to get good function and reliability.

[Lawrie]

Parts are easy to get, I just got a NOS Ford rotor and inner terminal plates,and dist bushes,as easy as an e/mail , I just wanted them for spares.
If you look in one of the ford service books for the 33/34 there is a real gem of a tester in there,easy to make using a model T coil and 6 v torch battery,I test all my HT stuff on it,.
Like Koates said the stock stuff is VERY good.
Lawrie