Topic: 1952 5hp Firestone magneto cam – Antique Outboard Motor Club,Inc

This topic has 9 replies, 7 voices, and was last updated 1 month, 2 weeks ago by Tubs.

Viewing 10 posts - 1 through 10 (of 10 total)

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December 28, 2025 at 12:45 pm #302698
James Douglas
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US Member
I cannot figure out how the points are supposed to open when the cam has a flat face a tdc rather that a bulge? I’m really missing something here…
December 28, 2025 at 12:46 pm #302699
James Douglas
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US Member
December 28, 2025 at 1:37 pm #302702
DAVID
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US Member
Just move the point to widest opening on cam. the motor does not need to be on top dead center.
December 28, 2025 at 2:10 pm #302703
James Douglas
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US Member
The cam is the same width all around except for the “flat” section shown in the photo…
December 28, 2025 at 2:53 pm #302704
JACQUES
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Canada Member
Check it with a micrometer don’t eyeball it . Do points open at one location as you rotate the shaft ? that is when it fires . the matching piston should be tdc or darn close to it

btw those condensers look iffy….

is this a new problem ….. a new to you engine

Joining AOMCI has priviledges 🙂
December 28, 2025 at 3:36 pm #302707
Buccaneer
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US Member
If you advance the mag plate to “Start” or beyond, are the points

just starting to open?

Prepare to be boarded!
December 28, 2025 at 4:25 pm #302708
James Douglas
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US Member
I picked this motor up to try working on something other than an OMC. The condensers are showing 0.2 mf. I think I need the oblong cam…
December 28, 2025 at 5:08 pm #302711
Tom
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US Member
Any chance the cam is in upside down? They usually say “TOP” on the top.

T
December 28, 2025 at 5:48 pm #302716
Sam M.
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Canada Member
To me, it looks like the brown piece that should rub on the cam is not touching the cam. Is part of the assembly seized? Also, don’t forgot to lubricate the felt piece – it looks dry.
December 29, 2025 at 9:04 am #302734
Tubs
Participant
If you have a piston positioned at TDC, the magneto is positioned for slow or ATC. Move the magneto counterclockwise to where the points just open and the plugs will be firing at TDC. Keeping moving the magneto and the plugs will be firing at BTC.

A "Boathouse Repair" is one thats done without having tools or the skills to do it properly.
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If you have a piston positioned at TDC, the magneto is positioned for slow or ATC. Move the magneto counterclockwise to where the points just open and the plugs will be firing at TDC. Keeping moving the magneto and the plugs will be firing at BTC.