Re-read your post: (“A DUAL ADVANCE requires a 12V neg. system”….)
A 6V condenser..sure. But, I don’t believe the 12V neg. points would have trouble conducting 6V + grd. current (unless there is some issue I’m missing?).
Re: ‘dual points’:  Since 6V electronic distributor options are quite limited, dual points may well offer longevity/reliability advantages in addition to better performance.

6 VOLTS/POS. GRD. NW INDIANA

Re-read your post: (“A DUAL ADVANCE requires a 12V neg. system”….)

An OEM DUAL ADVANCE DIST (1957/ ) requires a 12V SYSTEM, unless modified in a fashion to operate off a 6V SYSTEM.

This gentleman has a CHERRY 54 MERC SURVIVOR that he wants to remain as OEM ASSEMBLY.

He has a drive-ability concern that he wants to address while retaining the FACTORY ASSEMBLY LOAD-O-MATIC. I agree with his approach. He feels the problem is within his LOM DIST. I am just giving him the info and choices he is seeking

I realize my CRS is rapidly advancing and I cannot seem to understand where you are going.

Exactly what is it you are trying to get across?

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The LOM IGN SYSTEM required the DIST to be removed and set up on a DIST MACHINE (whether a tune-up or drive-ability concern). 

Points dwell, breaker arm tension, and advance curves were verified and corrected at that point. The DIST was re-installed and if drive-ability was still a concern, the MECHANIC/TECH would go into the fuel and advance signal system.

You can use timing tapes, an extremely sensitive vacuum gauge along with prayers and hopes until the cows come home.

There are PERTRONIX SYSTEMS that will replace the points/condenser on a 6V (POS or NEG GRD) LOM DIST. That takes care of any DUAL POINTS setup.

The points style DIST was phased out in 1974/1975 production and for good reason (IMO).

Would I personally use a LOM DIST? Not unless the car was a survivor or correct restoration.

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OK KULTULZ, here is the one with no tag.


BTW I'm wondering if my mechanical DIY ignorance got me to this point: could the whole misfiring issue have started not from the LOM 'peculiar' tuning but from an EXPANDED shaft lobe, that was heating up because of the constant rubbing on the brass bearing? Just a thought, because I have put on 30,000 miles and I don't remember when the misfiring problems started. And of course back then I did not read (or understand?) my manual's clear instructions on having a 0.020'' gap under the lobe ...

Here is the pic of the one I had on that was misfiring. Again I have no recollection of how long it had been operational on the car to relate it to when the misfiring started. Memory was always one of my weak points but now at late 70s it is much worse....

... could the whole misfiring issue have started not from the LOM 'peculiar' tuning but from an EXPANDED shaft lobe, that was heating up because of the constant rubbing on the brass bearing?

Yes. If the bushing is worn, it will allow the DIST SHAFT to wallow and the points opening and dwell will be affected.

[B[ EDIT[/B] - If the shaft is not in correct alignment (defective bushing) it may also cause excessive wear of the actual cam (and points set rubbing block) also, especially if not lubed correctly during service.

There is an oil cup in older DIST that allows the bushing to be lubed at service intervals.

Can you wiggle the shaft and notice unusual excessive side to side movement within the bushing?

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Discussing CRS ... 

OK KULTULZ, here is the one with no tag.

Actually, it is an IDENTIFYING TAG but just in another format.

HOLLEY was the vendor for FORD IGN and FUEL for that period. It may be the tagged ones were issued at the CLEVELAND PLANT and the bowl ID was issued at the DEARBORN PLANT.

The DIST tagged FAE-12127-C is the correct DIST for your engine (CLEVELAND ENGINE - CF).

FAE-12127-A is a DIST (13T) for the DEARBORN plant (DIF) and was issued for the light and medium truck 239CI.
Usually, when a PN SUFFIX ( -A in this instance) had a numerical character after it ( -A2 in this instance), it was an indication of an upgraded/improved replacement PN. FAE-12127-A2 is not cataloged so it may have been described in a SERVICE LETTER of that period.

Regardless, hold onto the original DIST as it will increase the value of the car.

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6 VOLTS/POS. GRD. NW INDIANA

Back on page 6 Aris said he took the 13 tooth gear off his NOS distributor and put the 14 tooth gear on.  I thought 239s and 256s had 13 tooth gears, '55 and later engines had 14 tooth.  If the distributor he took out of the engine  had 14 teeth, then he doesn't have a '54 engine.  Or a '55 or later camshaft has been installed, which is not a direct fit in '54 engines.  Maybe someone has put a '55 or later short block in his car.

John - "The Hoosier Hurricane"

Back on page 6 Aris said he took the 13 tooth gear off his NOS distributor and put the 14 tooth gear on.  I thought 239s and 256s had 13 tooth gears, '55 and later engines had 14 tooth.  If the distributor he took out of the engine  had 14 teeth, then he doesn't have a '54 engine.  Or a '55 or later camshaft has been installed, which is not a direct fit in '54 engines. 

There were two 1954 FYB engine series -

- the DEARBORN built 239CI which was the EBU BIG CAM ENGINE and had the 13T cam drive.

- the CLEVELAND built 239-256CI which were the SMALL CAM ENGINE(s) (EBV and EBY respectfully) and required     the 14T cam drive.

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It most certainly is possible to improve performance with a LOM install, but the subject was SERVICE REPAIR, not SERVICE UPGRADE or MODIFICATION. The OP wants the car to run correctly in it's original assembly 



No need for a restoration. Did you see the under hood shot(s)? Which method is going to result in a more valuable car, the OEM system(s) or a resto-mod?

THANX! for finally coming to your point.

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