model B distributor

C

coatings03

Member
I'm needing some advise and direction on using my recent purchase of a model B distributor. I understand they work on the Model A engine, however to get to 29 degrees timing advance the Model B engine was already 8 degrees starting out. How can I use this distributor in my model A engine if I can't get up to the correct timing?

Appreciate your help.

Jim M.
 
Vince Falter at his worthwhile site has good information on the Model B distributor (and it's application to the Model A or visa-versa.)

Your best solution may be to secure a Model B timing gear cover.

But check out Vince's site. The late Model A timing gear cover (with the extended boss for the timing pin that might be modified for the Model B use) you may already have.

http://www.fordgarage.com/pages/timingiseverything.htm

Joe K
 
You just start the rotor more advanced than the A would be. I have one in my car and just installed one in another car last night. Took about 15 minutes last night to get the timing tuned in and then she purred like a kitten. If you do install it make sure you have the longer spark wires, the shorter ones wont reach.
 
Suggest you do a search on this topic . If this is an original B dist. there is some information from a prior post that states the original B dist had a spring design flaw such that they ran retarded . Also suggest you use a B timing cover .
 
Hi 03,

1. If you have a Model "B" distributor on an "A" engine or on a "B" engine, ...... & you have installed a Model "B" timing cover, ......... the timing pin's location is in the correct "advanced" position whereby you can time your "A" or "B" engine with the correct "B" timing pin location such that when the timing pin slips in the "B" timing cover, the distributor cam & rotor should be adjusted & positioned correctly like that recommended for either Model "A" or Model "B" distributor timing.

2. However, if you have a Model "B" distributor on an "A" engine or on a "B" engine, & ......... you have installed a Model "A" timing cover, ............. the timing pin location is in a "retarded" position for operating these engines with a Model "B" distributor.

3. Timing a "B" Distributor w/an "A" Timing Cover:

A. Just one (1) quick & accurate way to time a Model "B" distributor on a Model "A" engine ............ or a Model "B" engine .............. with an installed Model "A" timing cover ............ is to first buy & install one of these $35.00 or so SS Model A timing devices sold on E-bay that mounts on one's timing cover & accurately indicates timing degrees immediately above the crankshaft pulley.

B. Next, remove spark plug No. 1 to "correctly" find "exact" position of TDC of piston no. 1, (nearest the radiator), & with the crankshaft pulley in this no. 1 piston TDC position, file a vee groove mark in the crankshaft pulley immediately below the zero (0) degree mark on the SS timing device. (Mark the bottom of this vee grove with white paint such as that similar to typewriter correction paint so it can be readily seen later.)

C. Then rotate the engine & crankshaft pulley "clock-wise" until the above first filed vee mark is directly below the "19" degree mark on the SS timing device; (passenger's side of zero (0).

D. With the crankshaft in this "19" degree advanced position, adjust the Model "B" distributor cam & rotor like that for adjusting same for Model "A" and/or Model B distributor timing.

E. The metal distributor upper plate adjusting tab at the rear of the distributor can be used to move back & forth for advancing or retarding the spark for fine tuning "if" necessary.

F. Either a Model "A" engine or a Model "B" engine ....... with a "properly" timed & properly adjusted spark, ..................... with a Model "B" distributor .......... can be safely hand cranked with no kick-backs "if" timed correctly & accurately.

G. For those trying listening & guessing for the "Sweet Spot" method for timing Model "B" distributors & later "hand-cranking" .............. one (1) word of Caution: ..... one better be able to accurately hear & differentiate the difference between "Sweet", .... "Sweet-Sweet", ....... "Sweet-Sweet-Sweet", ....... & "Not-As-Sweet-As-I-Thought", after one's arm is in a sling.
 
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I had a B distributor on my A. Just set the timing pin as you would on the A. Then set the points just ready to crack. If you are blind like me, use a test light like you do on a motorcycle. By the way, the B distributor sits higher so the plug wires were too short. I bought a mountain dew, and after a short pause to quench my thirst, cut new wires. I love the model A! Grandpa used to say you could fix anything on a model A with a screwdriver and pair of pliers, guess he was right.
 

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Little Sime said:
I had a B distributor on my A. Just set the timing pin as you would on the A. Then set the points just ready to crack. If you are blind like me, use a test light like you do on a motorcycle. By the way, the B distributor sits higher so the plug wires were too short. I bought a mountain dew, and after a short pause to quench my thirst, cut new wires. I love the model A! Grandpa used to say you could fix anything on a model A with a screwdriver and pair of pliers, guess he was right.
Click to expand...
Nice plug connecters,May be on to something there.:confused:
 
Little Sime said:
I had a B distributor on my A. Just set the timing pin as you would on the A. Then set the points just ready to crack. If you are blind like me, use a test light like you do on a motorcycle. By the way, the B distributor sits higher so the plug wires were too short. I bought a mountain dew, and after a short pause to quench my thirst, cut new wires. I love the model A! Grandpa used to say you could fix anything on a model A with a screwdriver and pair of pliers, guess he was right.
Click to expand...

The problem with this is the timing pin hole on the B timing gear cover
is in a different location than on the A cover.

Bob
 
H.L. great post. ive bought a B distributor and using an A timing cover. in step 3b cant I find tdc using the pointed timing case bolt to assure tdc? in 3c your actually turning the crank about 350 degrees clockwise to get to the 9 degree mark after installing the new pointer and marking the pulley.
 
Hi cfordman,

A. Yes & yes.

1. 360 degrees - "19" degrees = "342" degrees & because "original" Ford crankshaft pulleys are approximately the same diameter as the timing gear, "19" degrees is approximately between "7/8" " when marked on the circumference of a Ford crankshaft pulley.

2. If just eyeballing for a very "rough", double-check timing dimension, "19" degrees BTDC measured on the circumference of a Ford crankshaft pulley is approximately "7/8" " on a measuring tape.

3. Also, B distributors work extremely well in stop & go traffic where ignition timing is coordinated with engine speed, thus giving top engine performance on acceleration & pick ups, and also can assist obtaining good gas mileage.

4. Also good in many ways if your children or a friend borrows your car occasionally -- frankly, I am passed the stage of trying to show people I know how to adjust a Model A spark lever.
 
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will be installing b dist tomorrow. with crank rotated to 9 btdc and points set to just open and rotor facing #1 what will be the relation of the rotor to the number one dist cap pin? will the pin point to the trailing tip of the rotor like an A or does it really matter as long the rotor crosses #1 dist cap pin when the points break.
 
Many do it differently, but in the end, if points are closed, ignition switch "ON", if one takes a wood or plastic handle screw driver & open the points, as soon as the points open. the coil wire will immediately spark.

I set both A & B distributor so when pin slips in, points are closed, but just about to open; however, most plastic rotors have backlash on the distributor cam, & the drive gear could have excessive backlash if worn so one has to insure to remove all backlash.

After initial setting, I always turn the crank again, allow the timing pin to slip in & hit bottom, & with very little turning of the crank, when the pin first begins to be pushed out, the points open & the coil wire fires.

In 99% of the cases, because of doing it for so long, it is right on the money.

Then if checked with a timing light, it is right on again.

Just different ways to lace shoes & tie shoes -- & each to his own liking.
 
h.l. always glad to hear from you. my question is ( im using b dist and a cover) there is a refernce photo that shows that if the timing on an A dist with an A cover is set correctly the trailing edge of the rotor is across from the #1 cyl dist. I was wondering when setting the b dist points to open at 9 degrees btdc where is the rotor edge to #1 dist pin or is it important as long as the rotor is somewhere across the dist pin.
 
Maybe look at it like this:

1. The spark is coming from the coil, through the coil wire to the rotor, whereby the metal extension on the outer edge of the rotor has to be in a position opposite the No. 1 distributor electrode to throw a spark to the No. 1 plug "immediately" when the points open.

(FWIW: This coil electrical spark travels at the speed of light in a vacuum, & almost the speed of light in air, so don't think about trying to change the speed of light with a Model A spark lever or by adjusting the top plate on a Model B distributor -- in other words no matter where the metal tab is on the rotor, centered or opposite on the trailing edge, when the points open, No. 1 plug will fire.)

2. Taking the above into consideration, I was shown this in the late 1950's when changing distributors back & forth & changing timing covers back forth:

A. If one is timing a Model B distributor with a Model B timing cover, the distributor rotor's metal tab's center will be close to the center of the No. 1 electrode; &

B. If one is timing a Model B distributor with a Model A timing cover, the distributor rotor's metal tab's trailing edge will be close to the center of the No. 1 electrode.

C. Also note that a very worn drive gear on a worn cam spiral gear coupled with worn distributor shaft(s) slots, that this wear can have an effect on this position of the rotor.

D. I personally never timed Model A's or Model B's by looking at the rotor; however some do & also there are many different ways to correctly time Model A & Model B engines.

3. Lastly, if you installed new bushings in a Model B distributor, do not forget to drill a hole in the side of the bushing so oil can get to the shaft.

Hope this helps.
 
yes sir! that's exactly what I thought as long as the rotor tip covers the dist pin when the points open the plug will fire. I was trying to validate that the cam position and point opening were in the ballpark by looking at the rotor. carl
 
Hi Carl,

Also of interest maybe only to Model A speedsters, in the April 1994 "Secrets of Speed" magazine, Mr. Charlie Yapp, reprinted from the Sept./Oct.1963 "The Restorer" an article on soldering 3/16" metal strips on both sides of the metal tip on a Model A/B rotor so that after providing even more advanced timing at higher speeds on racing engines, the spark jump from the rotor at idle or spark jump at full throttle would not have to be stretched out & weakened.

But here again, no matter what is the position of the metal on the rotor, the spark is immediate & is extremely quick when the points open.

Mr. Yapp was always a very interesting person to speak to about increasing performance of Model T, A, & B engines.
 
h.l. I got the b distributor in and running it is dead on 9 btdc. new problem is it wont advance. turning the rotor ccwise it feels really sticky but does return slowly. I think it should turn freely and have good spring tension on return. wife wants a daytrip and with temps near 100 in the garage I could use it. will tear into dist Thursday is there a common problem like gummed up bushings? my ebay seller gave me a discount because the bottom slot was bad, its a one piece shaft, I built it up and recut the slot. im goin to make this work.
 
Hi Carl,

The B distributor has two metal counterweights inside that should very easily open with centrifugal force as distributor RPM's increase & they should very easily return with spring tension as distributor rpms decrease.

The rotor should easily turn CCW & spring back rapidly after the distributor is installed.

It is possible that there was some type of lubricant used in the counterweight area whereby the volatiles from this old lubricant evaporated thus causing these weights to be sliding in a gummy substance.

Best to investigate, clean if dirty & re-lubricate with a light coat of motor oil.

Might also be a good idea to see if oil added in the side oiler can get to the main B distributor shaft & that oil entry to the shaft is not blocked by a distributor shaft bushing with no drilled hole provided.
 
h.l. got back to the car today. everything seems to be correct. nos points gapped .021, timing mark at 9 btdc puts number 1 dist pin in the middle of the rotor. car starts and runs timing light shows right on 9 btdc. when bring up the idle it advances only a couple degrees. I had taken the top plate off cleaned everything put light oil on pins and weights. moving rotor it moves weights out and they spring back. the dist shaft is free with no play. ques: how high to I have to bring up rpm to see a change and how much max can I expect to see? ques: is it possible the springs are too strong maybe incorrectly replaced over the years and are B springs available? ques: since the speed of the dist shaft throws out the weights is there a way to bench check it with an electric drill to watch the weights. is it safe to remove the springs and run it and check advance with a timing light? im sooooo close. thanks again. carl
 
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