I have a 54 Merc, 6 volt and staying that way for awhile. I’m installing a 292 (1962 block) and a new vacuum advance distributor (post ‘57) from NAPA. Stupid question....do points/condensers know if your running 6 or 12 volts thru them? If so, are 6 volt point/condensers available for a post ‘57 Y block dizzy? Will the ‘54 points/condenser work in the post ‘57 unit? As always, all help is appreciated

John O

 

The points don't know, but I've heard that the condenser should be for the voltage you are running. Since I've said that, I put 12v condenser in a 6v tractor one time and it worked just fine, as a matter of fact I don't remember if I ever replaced it.

ps what you should really do it get a petronix ignitor and eleminate the points. I did that on my 65 Mustang and it starts better with seemingly better performance.

 

John,

They are different sets, '54 vs. late dizzy. The NAPA dizzys usually have points already installed, though the gap/dwell may be off.

I don't know if there are any specific 6V sets for the later dizzys...probably not. It's been a long time since I've seen vintage 6V sets, but they always seemed to be a little larger on the contacts. Everything I've seen for quite a few years looks the same, regardless of the application...kinda cheap.

For the most part it won't make any difference. Since the current (not voltage) is higher, you may notice that life is slightly reduced...or, you might not. Either way I wouldn't worry about it. Theoretically condensers can even be matched for a 12V application for optimum point life, but I've forgotten how to select the right one, & I doubt there is really much choice offered nowadays.

NAPA or Standard Motor point sets seem to last the longest. Carquest does, or did, use Standard Motor sets, reboxed. The last NAPA set I bought was a Standard Motor, too.

 

Thanks Mike & Merlynr,
I swear I'm not as dumb as I may sound at times.
John

 

John,

The only thing I know about English bikes & cars is...Lucas electrics. A short story:

 

Ha! The first thing you do when you purchase a Brit bike is carefully remove all the electrical components and store them in the same area you put the load-o-matic dizzys I love the classic iron from an aesthetic point of view. However, safe and enjoyable my aim. My Brits get gutted, rewired and solid state components added. I have had many a battle with the "Prince of Darkness" over the years.

As with all things...if you have the proper guidance and some patience nothing is insurmountable.

 

A "condenser" is just a capacitor. A capacitor is simply a charge storage device consisting of parallel plates to store this charge.

The voltage rating is directly related to how close the plates are to each other so the voltage limitation is only a "how high" type limitation.


Higher voltage capacitors will work just in lower voltage applications. Since the voltage limit is just a point at which the capacitor may arc-over.


Just about any "condenser" will work in your application. If it's too HI (too many Microfarads) it will transfer metal from one side to the other in your points. if it's too low....same thing will happen to the other side.




Here's a simple and excellent explanation of how it works etc, complete with a good diagram!




Merry Christmas!




Rick

 

I had always assumed that the condenser and the primary side of the coil formed a tank circuit tuned to the frequency that the engine runs at.

The point about things being basically about current, not voltage is a good one. Having said that, be sure you're using the proper voltage coil. The coil is a step-up transformer. The step-up ratio for the 6 volt coil is higher than the ratio for a 12 volt coil. Too high a voltage is hard on both the points as well as the spark plugs.

 

1954 -1956 239-312 Y block (1954-55 6V)

Points: FAB-12171-B
Condenser: B7A-12300-C
Rotor: FAA-12200-B
Cap: FAB-12106-A

***

1957/ 292/312 (and 221; 260; 289; 302; 332; 352; 390 etc).

Points: B8Q-12171-A
Condenser: B9A-12300-A
Rotor: B7A-12200-A
Cap: B7A-12106-A

 

A tank circuit? Maybe a Pi network?

Nah.....more like a link coupled L network! ( I know, I have way too much time on my hands!)

 

John,


By the way,

I also have a 292 with a later distributor for my 55 F-600.

I also installed a Pertronix igniter and Pertronix coil but I used it with the OEM coil and condensor for quite a while. I would never go back to points.



Regards,



Rick

 

Here's where someone always annoyingly pops in and suggests installing a pertronix.. Real helpful, huh I gotta admit - saves a hell of a lot of hassle?

But I keep a set of points and condensor in the glovebox "just in case" the modern gee-whiz solid state IC shorts out or whatever, and I know how to install and set well enough so the goddamned thing will get me out of whereever the hell it is I'm at. In fact, one of the reasons I have the two photographs in the profile is because ole' blue (I think) vapor locked on me at altitude. Engine died just like a switch was thrown. After a few choice words and a look under the hood, it fired right up again. Still running points on that run. So far haven't needed to reinstall them - but the option is there.

I'd also try to find a couple sets of 50's or 60's era NOS and use those, should be cheap and plentiful - the quality of modern units aren't too good so why bother with them.

The problem with points is that unless you adjust them fairly often, one partly forgets the procedure in part - when the dwell is changed the timing must be re-set. Where's the feeler gage again? And why did Ford put the rotor waaay back at the firewall anyway.. And the gap set with the feeler gage doesn't quite correspond with the actual dwell. Then, add in the slop in the by-now well-worn dizzy, the slipped harmonic balancer indexed to the timing marks - and timing can be kind of a hit or miss thing.