Distributor help?

Bassman/NZ

Bassman/NZ

Well-known member
I have a C59A and I have converted the rabbit ear dissy to a crab type with all new parts, including new vacuum brake. The engine is running fine, but I dont know how much tension to put on the vacuum brake, and where to set the little advance/retard plate. When I move it, it seems to make little difference. I could just leave it as is because it runs well, but my built-in desire to fix things that aren't broken is overwhelming...... :D
 
Vacume brake almost all way out ,be careful on this [with fingers]. Advance and retard plate move to middle or 1 hash mark up from middle.ken ct.
 
Bassman, The vacuum brake being new, you may have to check this again after it runs in a bit depending on the leather. The brake is needed to prevent the advance from running up to fast. With today's gas being much higher octane than was available back in the day, the original purpose to prevent pinging is negated, as you have discovered. Today, it is needed only to prevent the advance disk from bouncing eratically. Just snug it lightly as Ken advised, and you're good to go.
 
If the cylinder wears the vacume will not lift the piston, the vacume excapes on the sides of the leather and the piston just sits in the cylinder jiggiling up and down, it won't lift. This is one reason why the distributors need to be set up on a machine as well as proper timeing. Just guessing don't work it's pure luck if it does. G.M.
 
KenCT and G.M know their stuff. I follow their advise. Ford38v8 also brings up a very good point. Back when these cars were built octane rating was something like 60. The lowest pump octane in my area is 87. Mine likes the stuff.
I'm glad you're in the same mode as I am when it comes to the care of our V8s. so I am returning your quote from when I was running down my overheat issue. "If it aint broke, fix it 'til it is!". All kidding aside, keep the rubber side down and enjoy life in an old Ford.
 
Hello All. I found that my 46 conv has no vacuum break cylinder, and the vacuum line to the dist has been plugged. Have been driving the car this way for over 3 years that I have owned it. Some local driving, but also several long trips. Skip has 2 of my distributors that he is setting up for me. Been thinking about doing the same thing---no vacuum break on my 46 Cp. What do you guys think? Thanks, Tom..
 
The reason the brake needs to remain on a setup that has no pinging and runs fine with adjustment all the way out was something I never thought of until Ron discussed it:
The forward plate on the advance governor assembly is the brake disc, and it is free to float rotationally on the shaft and will in floating alter the location of its slots which control the limits of weight movement. Ron discovered on a distributor machine test that this allows, actually forces, timing to drift to and fro as the plate moves.
Leaving in the brake puck puts a slight drag on the thing and keeps it in place.
The reason more tension is not needed is that modern gas is higher octane than Ford prepared for and the quickest curve the distributor is capable of is about right.
 
There is a post from years ago on setting up a crab on the Ham by some one ,along the lines of moving the advance plate up one notch .As i have said before using stock Ford points you may get away with it as a short term fix but its not really the way Ford did it . its even more critical using after market points .,Ford gave 2 pages of instructions on how to set them up .you need to consider things like rubbing block ware this needs to be matched to the cam as per the ford book ..the stronger the spring the greater the ware ,Spring tension 22 ounces ,Later points had stronger springs for higher reeving cars .Also when you add a adapter plate with with a 6volt coil you have altered the Ford circuit,there goal was 50.000 miles per rebuild .So with this new circuit what value condenser are you going to use ,What about the ballast resistor ?? By far the greatest failing's in points ignition is burnt and closed up points,not to mention cooked coils . Its rare to see any ware in the vacuum piston , I have had good results with running the bolt fully up then down 2 turns .the comments confirms why ,this adds a little tension on the disk, When backing out the bolt watch you don't pull of the washer on the end .
 
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