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Old 05-18-2020, 09:33 AM   #1
Robert/Texas
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Default Distributor Problem

I’m having a problem with the distributor in my ’28 roadster. I replaced it in 2001 with a newly manufactured one with original style points from Bratton’s. Since then, I’ve only accumulated about 4,500 miles on the car and haven’t touched the distributor until now.

I noticed that the point arm contact and the point block were worn to the point that further adjustment was impossible, so I decided to replace these with a new point assembly. When doing this I found that the replacement arm in the new point set was too long to make much contact with the opposing point. To correct this, I replaced the point block with a “machined” type purchased from Bratton’s. This solved the length problem, but the two points are now not completely parallel. (They would be if the points were set much, much wider).

Setting these points at .018mm with a feeler gauge and timing the distributor per the Les Andrew’s manual, here is what happens. At full retard, the engine starts instantly and when advancing it, it speeds up like it should until it it’s about 3/4 advanced like it always has but it runs extremely roughly and sometimes backfires. I think that all this is about what I described above but still it could be due to other problems.

I’m thinking about replacing the points with a “modern” style system as is recommended in the Les Andrew’s manual but would appreciate other help/suggestions.

Thanks in advance, Robert
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Old 05-18-2020, 09:50 AM   #2
Greg Jones
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Default Re: Distributor Problem

Robert, I went through the same thing as you. I used the Bratton's "machined" point block (part no.. 17531 I believe). I found I had to tweak the mounting holes in the upper plate so as to enable setting the points square. By tweaking, if I remember correctly, I had to wallow out one of the mounting holes to enable the point block to rotate into a square position. (Hopefully this makes sense) I would encourage you to do something like this, as the modern system can also have its own set of problems. Another option is to find older points-they are out there. The problem is that the new points are made too long.
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Old 05-18-2020, 11:57 AM   #3
katy
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Default Re: Distributor Problem

[QUOTESetting these points at .018mm][/QUOTE]

Methinks you meant .018 inch, not mm.
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Old 05-18-2020, 12:38 PM   #4
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Default Re: Distributor Problem

What Greg said about the mounting holes, a little adjustment.

With new points, try setting them initially at .022" and lube the cam. The block will wear kinda quickly at first.
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Old 05-19-2020, 07:54 AM   #5
Robert/Texas
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Default Re: Distributor Problem

Thanks Greg, Katy and Patrick.

It looks like the points are in near perfect alignment when they are at around 1/8 inch or so open. What happens is that when adjusted @ .018 inches, they close at a front to back angle. I’m a product of the great depression and seldom throw anything away which I think I may use. I even have some stuff that I’ve had since the.1950’s. Right now, I’m recovering from minor surgery and when I feel better, I plan to search through this stuff as I know there are some distributor parts there. Hopefully, something can be salvaged for this project.

Robert
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Old 05-19-2020, 10:13 AM   #6
Purdy Swoft
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Default Re: Distributor Problem

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The model A can run good with the points set at eighteen thousands . With a gap of eighteen thousands , the points are on the edge of needing to be opened up a bit . I prefer to start off with a gap of twenty two thousands . The wider gap gives more time before the engine begins to lose power . Ford recommended a points gap of anywhere from 18 to 22 thousands . Less gap retards . More gap advances . As Pat said in post number 4 , the points rubbing block will wear quickly and cause the points gap to close . A wider gap advances the timing and gives quicker throttle response .

Last edited by Purdy Swoft; 05-19-2020 at 10:18 AM.
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Old 05-19-2020, 08:22 PM   #7
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Default Re: Distributor Problem

Quote:
they close at a front to back angle
It sounds like the stationary point needs to be repositioned a smidge.
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Old 05-19-2020, 10:26 PM   #8
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Default Re: Distributor Problem

Quote:
Originally Posted by Purdy Swoft View Post
The model A can run good with the points set at eighteen thousands . With a gap of eighteen thousands , the points are on the edge of needing to be opened up a bit . I prefer to start off with a gap of twenty two thousands . The wider gap gives more time before the engine begins to lose power . Ford recommended a points gap of anywhere from 18 to 22 thousands . Less gap retards . More gap advances . As Pat said in post number 4 , the points rubbing block will wear quickly and cause the points gap to close . A wider gap advances the timing and gives quicker throttle response .

Actually, point gap only affects the timing at full retard (timing lever all the way up for starting). As soon as the engine starts and the driver pulls the timing lever down, the timing is under his control. If he feels that the timing is a little retarded he simply pulls the lever down a click or two. If he feels the timing is a little too far advanced, he moves the lever up a click or two. As long as the point gap is between the usual .018" to .022" the engine will run fine as long as the driver uses the timing lever properly.
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Old 05-20-2020, 05:24 AM   #9
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Default Re: Distributor Problem

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Originally Posted by 40 Deluxe View Post
Actually, point gap only affects the timing at full retard (timing lever all the way up for starting). As soon as the engine starts and the driver pulls the timing lever down, the timing is under his control. If he feels that the timing is a little retarded he simply pulls the lever down a click or two. If he feels the timing is a little too far advanced, he moves the lever up a click or two. As long as the point gap is between the usual .018" to .022" the engine will run fine as long as the driver uses the timing lever properly.


Base/initial timing is just that. Point gap affects that. Wherever the left lever is set is an afterthought in that it all starts where the base timing is set. That lever can make up for late timing by pulling it down a couple clicks. It can not make up for early timing when the lever is fully up.
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Old 05-20-2020, 06:40 AM   #10
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Default Re: Distributor Problem

There are some other things to consider when "messing" with a distributor. 1) Are the lobes on the cam (all 4) the same height. If one is worn more than the others, I have seen as much a .005 difference, then the points will not open as far on that lobe. For example- if 3 lobes are set at .018 and one lobe is worn .005 , then it will open only .012. Check your point gap at all four lobes and you can determine that hiccup. Some cams wear differently and others , were manufactured inconsistantly.


2) Are the tits on the distributor body consistantly equal distance from the end of the rotor. They should all four be approx.025. Got some leeway here, as much as .005, but they should all be consistant. If not consistant then the distributor body is warped. This wont affect timing but will affect smooth running.


3) Back to points. If not closing square, at full retard, a point file or fine emery paper should be able to correct the square. Down side of this is each time you reset points the offsquare will show up again.


4) If new points start off with .022. They will wear in pretty quickyl. With old points or resetting existing points the .018 is good.
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Old 05-20-2020, 05:18 PM   #11
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Default Re: Distributor Problem

I finally got to feeling better and worked on the distributor some more. Many thanks to all of you who have been helping me with this.

I fiddled with the point block some more and was able to get the alignment a lot better. I filed the points lightly with a point file and set them @ .022” after replacing the cam with a B style one. I timed the engine and it started right up and runs smoothly. It’s a little too far retarded though and I’ll work on that tomorrow.

Thanks again, Robert
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Old 05-21-2020, 12:25 AM   #12
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Default Re: Distributor Problem

Quote:
Originally Posted by Robert/Texas View Post
I finally got to feeling better and worked on the distributor some more. Many thanks to all of you who have been helping me with this.

I fiddled with the point block some more and was able to get the alignment a lot better. I filed the points lightly with a point file and set them @ .022” after replacing the cam with a B style one. I timed the engine and it started right up and runs smoothly. It’s a little too far retarded though and I’ll work on that tomorrow.

Thanks again, Robert
You can fix that retarded timing in about 5 seconds! Just pull the timing lever down a couple clicks. Presto! Timing is adjusted. The timing advance by using the lever is about 40 deg., from full up to full down. You will never need all 40 deg., so there is plenty of timing adjustment using just the lever.
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Old 05-21-2020, 07:31 AM   #13
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Default Re: Distributor Problem

If the base timing is a bit retarded, thats not really a bad thing. I prefer that. I don't believe these monsters need a total advance of 40º.
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Old 05-21-2020, 10:16 AM   #14
Robert/Texas
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Default Re: Distributor Problem

I just got done with resetting the timing. The problem is that there is a lot of backlash in the cam which I believe is due to not having a lube hole in the upper distributor driveshaft. It’s really hard to get the timing adjusted under these conditions. I don’t plan to fix that because the engine runs well with this play and it did so for the 31 years that I’ve owned the car. The engine now puck-a-pucks at full retard and acts just like it should when advancing the spark.

Thanks again to all of you, Robert
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Old 05-21-2020, 11:20 AM   #15
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Default Re: Distributor Problem

I also just posted this on another thread. You already may be aware of this. The operators manual instructs to fill the oiler completely full to where it will not take any more. This is supposed to allow oil to migrate up into the upper bushing. I run across a few who only add a drop or 2 of oil when oiling the oil cup.
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