distributor rotation play

[Geno]

While replacing a bad timing gear, I decided to replace the points and condenser prior to setting the timing. First, I found the distributor case quite loose, but was able to tighten it up. Second, I noticed there seemed to be excessive shaft rotational play. I can't find any reference to any rotational tolerance specification. I am a newbie to working on a Model A engine, learning as I go. Does anyone know how much rotational play is considered normal?

[VFRhugh]

While your in there consider replacing the distributor Drive gear. Photo is one I replaced last year. It's a $25 part.
Hugh

[wmws]

I've never seen a spec on that but it is quite a bit. Maybe 30-40 degrees. Take the backlash out to time the distributer.

[Geno]

I figure it is a least close to 30 deg. I think I'll pull out the distributor as my end play also seems excessive. Has anyone an opinion on an original rebuilt distributor from Snyders? I will get into my repair manual and see what is involved in inspecting or replacing the drive gear

[midgetracer]

The drive gear is simple to replace. Hardest part is opening the valve cover, then it pops right out and if you drice out the pin on the sleeve, it will come apart. reverse to install a new one. Just do it.

[Tom Wesenberg]

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Originally Posted by wmws

I've never seen a spec on that but it is quite a bit. Maybe 30-40 degrees. Take the backlash out to time the distributer.

I've never seen a spec on rotational free play, but I'd never accept anything close to 30 degrees. Both ends of the shaft have slots that wear, and the drive and driven gears both wear. The drive gear being on the camshaft makes it hard and expensive to replace.

[H. L. Chauvin]

From past experiences, before people started restoring Model As, here is what is most important for proper timing of a totally worn out Model A with loose play at the distributor shaft ....... worn out Model A's run very well.

1. First set you point gap first.
2. Retard your spark with spark lever all the way up and very carefully time your engine.
3. At this point, after carefully timing one's engine, about 75% of Model A owners always incorrectly time their engines because they cannot comprehend distributor shaft and rotor loose play and backlash ...... but their is hope and a fool proof test for timing.
4. Remove all four plugs and connect grounded no. 1 plug to the distributor.
5. With ignition switch "ON", rotate engine with hand crank until timing pin slips in.
6. When timing pin slips in, no. 1 plug should fire when points open.
7. It does not matter if you rotor has free play, if your distributor shaft wiggles back and forth, or if your neighbor's daughter has wet bikini type underwear hanging on her clothes line ........ if no. 1 plug fired when timing pin slipped in, you are good to go.
8. Just try it "once" to see if your timing procedure is well understood and properly performed ...... it works well with Model A worn parts.

[Mike V. Florida]

Follow these instructions and you will allow for the rotational slop;

http://www.abarnyard.com/workshop/timing.htm

[old31]

Originally Posted by H. L. Chauvin

From past experiences, before people started restoring Model As, here is what is most important for proper timing of a totally worn out Model A with loose play at the distributor shaft ....... worn out Model A's run very well.

1. First set you point gap first.
2. Retard your spark with spark lever all the way up and very carefully time your engine.
3. At this point, after carefully timing one's engine, about 75% of Model A owners always incorrectly time their engines because they cannot comprehend distributor shaft and rotor loose play and backlash ...... but their is hope and a fool proof test for timing.
4. Remove all four plugs and connect grounded no. 1 plug to the distributor.
5. With ignition switch "ON", rotate engine with hand crank until timing pin slips in.
6. When timing pin slips in, no. 1 plug should fire when points open.
7. It does not matter if you rotor has free play, if your distributor shaft wiggles back and forth, or if your neighbor's daughter has wet bikini type underwear hanging on her clothes line ........ if no. 1 plug fired when timing pin slipped in, you are good to go.
8. Just try it "once" to see if your timing procedure is well understood and properly performed ...... it works well with Model A worn parts.

Sorry HL, but # 7 did not work for me. That's because you have just not seen my neighbors daughter and her bikini

[H. L. Chauvin]

Hi old 31,

I may have seen your cute neighbor's daughter last night at our local Outback restaurant where she ordered a salad and told the waitress she just started a new diet.

Because so many Model A owners might want to hear, while re-timing your Model A in a few weeks, please let us know if her new diet results in seeing positive changes on her clothesline ........ and/or if it affects your Model A ignition re-timing adventures.

[Kevin in NJ]

I would first ask why you felt you needed to replace the points or condenser?
Points only need to be replaced when they are bad otherwise you are wasting resources. A good set of points should last you decades unless you drive a heck of a lot. If you get a burn out proof condenser from A&L then you are likely to never have a problem there again.

The distributer has a bunch of considerations for best restoration. Clearly the bushings need to be tight. Loose bushings will not allow for the upper bushing to be lubricated as you might never get the side oil cup to fill up as per Ford's instructions (NO, Ford did not forget an oil hole here, people just are not following directions). This also leads to movement affecting consistent point gap.
What about the fit of the upper plate to the center bushing. Mine is measured to be about .002". A worn dist bushing area and a worn upper plate got close to .010" of movement.
Do not forget the cam. It must be smooth and even, have you checked the lift of each lobe? There are very high quality repros by Bill Stipe.

Anyway, some thoughts..

[Tom Wesenberg]

Kevin mentioned a smooth cam, and this made me think of the winter road salt storage season where most of us have to let the car set for 6 months in an unheated garage. This is the time to be sure the cam has a light coat of lube so it doesn't rust from the moisture in the air over the winter.

[wmws]

Tom, How do you lube the cam other than starting it occasionally. My car sits for maybe a month sometimes during salt weather.

[Mikeinnj]

He is referring to the distributor cam, not the engine camshaft.
Just put a light film of cam grease on it.

[Tom Wesenberg]

Originally Posted by wmws

Tom, How do you lube the cam other than starting it occasionally. My car sits for maybe a month sometimes during salt weather.

Yes, as Mike said I was referring to the distributor cam. As for good engine care I would put the car away with new oil and cap off the exhaust and oil fill by taping plastic bags over each. Rodents just love to nest in the exhaust, and moisture also travels through the exhaust and any open valves into the cylinder.

[wmws]

My mistake. I try and drive my car all winter except if there is salt on the road. The longest it might be laid up is about a month.

[Geno]

I removed the distributor and the lower shaft. The slot in upper end of the lower shaft and the mating tab in the distributor shaft were quite worn. The slot in lower end of the lower shaft looked good, I believe replacing these two shafts will take most of the rotational slop out. The end play in my distributor is quite bad, so I decided to order an original rebuilt distributor. I see the slots in the lower shaft are offset, how hard will it be to reinstall the distributor and line up these slots?

[Tom Wesenberg]

The head gasket pretty well centers the lower shaft, so turn it with a flat blade screwdriver until it drops into the driven gear shaft, then set the distributor in place and turn the rotor until it drops into place. I always fit the upper and lower shafts together first, just in case the slot may need a stroke or two with a file. I've had a couple that were a bit too tight. It only takes a second to file it, so that's no problem.

I also would wipe grease all over the shafts, or anti seize compound. They like to rust if left bare.

[Geno]

Just received my rebuilt distributor this afternoon. No time to install it today but I can tell you this distributor is tight compared to my old one. I will reply again after it is installed and timing set (my first time setting timing)

[Fred K-OR]

Originally Posted by Geno

Just received my rebuilt distributor this afternoon. No time to install it today but I can tell you this distributor is tight compared to my old one. I will reply again after it is installed and timing set (my first time setting timing)

Being this is your first time timing, you may want to get the NUREX timing tool. It comes close to getting the thing in time and then you can "fine tune" it from there. Get the one with the instructions on the handle. Have fun!

http://www.snydersantiqueauto.com/timing-wrench