3 bolt distributor

B

bottomfeeder pete

Junior Member
does anybody have the ruler method measurements for timing the 3 bolt helmet type distributor, all i can find is info on two bolt crab style. thanx in advance. Pete.
 
I can post the ruler method if you want. But I find it much easier to use the 'eyeball' method for setting the initial helmet timing.

First, hand crank engine so passenger side #1 cylinder is at or very close to top dead center firing position. Then turn distributor tongue so a rotor tip is pointing at #1 cylinder cap position. Gingerly insert tongue into off-center cam slot. You may have to wiggle the rotor a very small bit to get the tongue seated properly in the slot. That's it. 8^)

Jack E/NJ
 
If you're asking me Alan, no I don't have the Ford service bulletins. In my case, final timing is of course set by 'ear' by moving the advance screw & plate up incrementally by an index mark at a time till the engine starts pinging under load with an operational vacuum brake. Then I back it off an index mark to stop the pinging.

Jack E/NJ
 
(I waited for Alan to come back to this thread. He took the day off.:))

Jack,

You can set your timing anyway you want, BUT just so anyone reading this doesn't get the idea that the way you suggest is recommended by the rest of us ... it's kinda backwards.

If you asked many of us, the initial advance is set with the screw/scale/index THEN the "ping" is eliminated by adjusting the vacuum brake.

For BFPete, you can use Ken CT's method of .016 gaps and the index set to the third mark from the bottom (I think that's his late 30's settings. Excuse me if it isn't, Ken. It'll work anyhow). Unless you get really bad parts, you'll do just fine.

There's nothing like the flathead distributor to worry the dookie out of people. It's much more forgiving than you'd expect.
 
Neither 3 or two bolt ruler system is in the bulletins...they wre written for garages with the whole test machine or at very least the fixture.
The 2 bolt system is in the '46 service manual as a field expedient... many cheap aftermarket timing fixtures made for the 3-bolt distributors replicated the 3 bolt ruler system, but with a simple jig eliminating actual rulers...
Ford's take on the ruler system can be seen in an early ignition patent that would have placed a simple fixture right on production car firewalls...again, no rulers, but a replication of simple ruler alignment between drive tab and bolt holes. The ruler methods get you to nearly exact match wit a KRW fixture, putting things at the specified 4 degrees quite well.

From earlier post:

All pictures there are from the front view...get a distributor and get oriented. Beyond that, for mechanical convention, LEFT points are those on driverside, RIGHT points are passenger...the L opening when R is alreay open fires the spark...
So, put a ruler across BROAD side of the drive on back of distributor, turn it so edge of ruler bisects the upper hole in passenger side as the line in patent shows, broad side of drive facing generally down.
Retard distrib at the adjuster on side, then advance til L point opens...indicate this by test light or by placing thin paper between point contacts.
All timing is done with coil screwed on, as the spring thing moves the plate down a bit. Results will be very close to center of scale. Be sure you understand which way is advance on the timing screw scale...early and late versions have scale on opposite sides, so think rotation. Bruce
 
Thanks Bruce ,it all depends on which way your lookin at the dist.Yes Crabs are backwards from helmets.ken ct lol
 
Hoop>>>There's nothing like the flathead distributor to worry the dookie out of people. It's much more forgiving than you'd expect.>>>

Agreed. That's why my first post on initial timing or advance implied as being pretty simple. I of course set the advance index in the middle or even a bit retarded with no brake to make sure the engine starts and the starter doesn't have to struggle against kickback. Final timing or advance usually starts by incrementally setting the advance index according to my feel for how much the starter struggles against kickback. This sometimes results in more advance than the brake adjustment can handle to eliminate WOT load pinging. I then I have to back down on the advance index scale to quell the ping. I find that sometimes the brake spring and/or leather pad just don't provide enough pressure/friction against the breaker plate even with the screw turned all the way in. Maybe due to oil soaking, etc?

Jack E/NJ
 
Hoop said:
(I waited for Alan to come back to this thread. He took the day off.:))

Jack,

You can set your timing anyway you want, BUT just so anyone reading this doesn't get the idea that the way you suggest is recommended by the rest of us ... it's kinda backwards.

If you asked many of us, the initial advance is set with the screw/scale/index THEN the "ping" is eliminated by adjusting the vacuum brake.

For BFPete, you can use Ken CT's method of .016 gaps and the index set to the third mark from the bottom (I think that's his late 30's settings. Excuse me if it isn't, Ken. It'll work anyhow). Unless you get really bad parts, you'll do just fine.

There's nothing like the flathead distributor to worry the dookie out of people. It's much more forgiving than you'd expect.
Click to expand...
Yep the earlier ones 32-early 36 i set at .014 with the coil attached and with out the rotor in there.I put the rotor in after and check axiel play in the shaft and shim it to suit, minimal play as long as the shaft turns easily by hand.Must have a little clearance. Maybe like .001-.002 the most. Also when checking points and checking end play,the screw and index plate must be tight,as it pulls thewhole guts to one side slightly.ken ct/
 
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And read Ken's post twice more...Coil attached (or the contact post on '42-8) and screw snug is IMPORTANT as plate can move enough to mess up all your settings.
Ruler method for '42 has been excerpted and put online. I need to figger out magic pictures and post how to ruler time earlies...reading my verbal description hurts my head and I'm not sure it is followable.
 
With the poor quality of the current supply of points, the distributor should be set up on a machine. This will allow you to check for point bounce and binding points. Setting the gap and then checking the dwell on the car is the next best method. Timing is determined by when the break set of points open.
 
The dwell vs gap comparison will identify the garbage points with incorrect geometry... correct gap should give you very close to correct dwell, and vice versa...
You check dwell of each set of points then combined dwell.
For primitive people with no machine...the KRW fixture can do all the checks, but that also is expensive.
Look at the degree wheel setup shown in the old Echlin manual; now reproduced and available everywhere as '32-36 repair manual or something like that.
It shows how to check dwell manually with a simple degree wheel. I have a couple of those kits, but I posted on the HAMB how to build a good working replica using a little wheel available at Home Depot. Again, it is a verbal description that probably cannot be followed by a sensible person...I need to develop picture tech!
 
"The dwell vs gap comparison will identify the garbage points with incorrect geometry... correct gap should give you very close to correct dwell, and vice versa ... You check dwell of each set of points then combined dwell."

Bruce is on the money. You will see an indication of garbage when the "combined dwell" does not add up as it should. Bad rubbing blocks and pivot holes will allow you to set the individual gap/dwell, but throw out the total dwell. This is an issue/problem that is more quickly diagnosed with a KRW fixture than a Sun machine. You immediately recognize the problem.

Maybe some good advice. Really try to learn how the distributor works. Once you understand the operation, you will find out how really over-complicated most instructions are.
 
The machine is nice, the KRW is nice, but how many corner garages and dirt farmers had them when these cars were fairly new? Lots were maintained with a 29 cent Western Auto feeler set and the tools that came with the car from Ford...or less. Ford recognized its low tech customers (while encouraging dealers to get the machines) with those ruler instructions and gap specs.
We now actually need more tech because we have readily available garbage points and such as well as decent ones...and often we have no easy way to know what we are getting from a mail order source.
 
Here is an old HAMB post in which I describe how to build a Home Depot Ford dwell gauge essentially similar to the 1930's Echlin one:

http://www.jalopyjournal.com/forum/showthread.php?t=257066&highlight=points&showall=1

The thread is long and rambling...building the gauge starts waaaay down about post #83.
Required bits include the Home Depot degree wheel, an O-ring and dealer type keyring, and Ford cam length adaptor, along with a set of step drills. The steppers are used manually and move up one step at a time, allowing the conical transitions to keep the wheel properly centered.
If you have a '42-48 you will also need a can of Vienna sausages.
 
Guys i would like to add some more info to the thread.

Precise ignition timing is very nice but many will never see it .
First of all the engine needs a accurate timing mark on it some where. You or the engine builder should get this job done. I would suggest a strap of steel bolted across the cylinder head with the head removed. Using a threaded bolt i the center above the piston turn the engine all the way in one direction ( by hand) until piston top hits the bolt head, mark this position and turn engine the other direction until piston again stops against bolt. Mark this position as well. The distance between these marks is exact TDC....
A dial indiacator doest work here as each piston has a certain degree of rock and dwell at tdc making it pretty hard to figure.

Now lets look at the front mounted distributor . The timing slot in each distributor has approx 12 degrees ( 24 engine ) movement in it. I suggest setting the dwell and point gap etc on a test machine and running each unit in for some time to allow everything to seat.
We adjust the timing slot to be centered in the slot as our neutral position.
The ruler or KW Wilson tool does this job very well on the bench.....
The timing may now be advanced or retarded as needed or desired with the timing slot. AND based on the exact TDC marking you now have , you can measure with a timing light exactly where you are running the timing.
I guess we could take this another step and actually index the rotor phasing to correlate with cap contact etc. ( we do this with our electronic version).
However that could be the other side of being picky ....:eek:
 
On that...ALL off-the-motor timing, by ruler, by KRW fixture, by distributor machine, in other words ALL Ford methods, has to run on the assumption that about a dozen parts are genuine Ford, within specification, and unworn...this actually works better than many might expect, generally coming pretty close when TDC and static are accurately located and checked against the above, but there is excellent reason to mark the pulley and check...after all, it is juuust possible that someone might have bought a cheap timing gear or that something might have worn a bit in the last 70 years...
The job is actually quick and easy...Bubba's method is the best but is only workable with heads off.
On a together engine, an adaptation of the interference method above can be used to find TDC to very nearly the same level of accuracy.
I've posted the heads-on method several times, as well as a computation-free method of dividing a span of pulley into accurate degrees.
Yes, as Bubba points out, a real timing mark indexed to crankshaft is best, and getting to spec is actually just a starting point...engines are individuals, and have their own preferences on exact best timing.
 
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