Topic: 1930 Elto Senior Speedster Mag plate retrofit woes

This topic has 5 replies, 3 voices, and was last updated 5 years, 11 months ago by hans.

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May 24, 2018 at 11:45 pm #10032
Buccaneer
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US Member
So I found a flywheel and mag plate from a circa 1940 Speeditwin, as suggested,
to replace the totally Rube Goldberg affair that my Speedster came with.
My Speedster’s crankshaft fits the taper in the Speeditwin’s flywheel A-OK.

The Flywheel diameter is 9-1/2", a 1/4" larger than the wrong flywheel that was on it.
I can’t find a photo showing the flywheel to gas tank clearance on the old flywheel.
What’s the diameter of the original, hand cranked, flywheel?

Problem– the mag plate does not fit on the post on top of the power head, as the hole
is 3/16" too small. The mag plate "may" be bored out and still have enough "meat", or
the post that the mag plate slides on, may be turned down. (the upper crank main bearing
is in this post) I’d rather not turn down the post in diameter, as some day I’d like
to set it up with an original timer, flywheel, and coil, but I suppose a bushing could
be installed over the turned down post to bring it back to correct OD.

The bottom of the post appears to have a "seam", and may not be part of the crankcase casting.
(I guess if I would have been smart enough to stick a magnet on it when I was in the garage,
I could have seen if the post is steel, as the crankcase is aluminum.)
I have the crankcase all buttoned up now for sand blasting, but I was wondering if the post
would drive out of the crankcase along with the upper main bushing?
Just thinking that I could make a new post to fit the Speeditwin mag plate.
Suggestions on the best way to solve this problem most appreciated.

The flywheel arrived with no keepers on the magnets. I went to put some bolts
across the shoes for keepers, and there’s only magnetism between the two opposing
shoes, on one side of the flywheel. Is this normal for a "single fire" system?
Thanks!

Photos are of the Speeditwin mag plate and flywheel

Speeditwin flywheel size- 9-1/2"
Speeditwin magplate hole – 1-1/2"
Post on top of crankcase is 1-11/16"

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May 25, 2018 at 12:11 am #76665
pm-t2
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Canada Member - 2 Years
If the sleeve over the crankcase neck is steel, its probably just a spacer they made up to take up slack between the original neck and the Johnson mag plate they grafted onto it. Remove the spacer and see if your Evinrude mag plate fits on. A simple measurement sequence would tell you that ahead of doing any actual removal work. I bet that you’ll end up cutting that sleeve off and the mag plate will suddenly fit with minimal fuss.

The only way you’ll drive the original crankcase neck (you call it a post) out of the housing is if you break it off and destroy the entire housing. Its cast as one piece, and the bearing is a press-fit insert.

Knuckle-buster flywheel diameter is 9.500".

PM T2
May 25, 2018 at 1:39 am #76673
Buccaneer
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US Member
quote PM T2:

If the sleeve over the crankcase neck is steel, its probably just a spacer they made up to take up slack between the original neck and the Johnson mag plate they grafted onto it. Remove the spacer and see if your Evinrude mag plate fits on. A simple measurement sequence would tell you that ahead of doing any actual removal work. I bet that you’ll end up cutting that sleeve off and the mag plate will suddenly fit with minimal fuss.

The only way you’ll drive the original crankcase neck (you call it a post) out of the housing is if you break it off and destroy the entire housing. Its cast as one piece, and the bearing is a press-fit insert.

Knuckle-buster flywheel diameter is 9.500″.

PM T2

PM T2, I see why you get paid the "Big Bucks"! It didn’t cross my mind that my Speedster
already had a sleeve on the "post / neck" to make it a larger OD, and hence, fit the
mag plate from Rube Goldberg affair.
I should have asked the audience the Timer ID, or the Neck OD on an original Speedster of 1930.
Didn’t think of it, but probably no one else has one apart to measure anyway.

In looking at my photos again, on the top side of the neck, there’s a lip, that appears to
be less than 1/8" wide. I need the neck to be 3/16" thinner total diameter, and if that is a sleeve,
that might just "do it" as you say.

Not sure if my bearing puller is thin enough to bite into that seam in the bottom
of the sleeve. If not, any good ideas on how to pull it off?

Sounds like I’m good to go as far as the flywheel OD……. great!
Thanks again!

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May 25, 2018 at 1:57 am #76678
pm-t2
Participant
Canada Member - 2 Years
Yeah you should see the year-end bonus I get from the club for dispensing my words of wit.

You can get scientific with the sleeve removal, and try to heat the steel to see if it will slip off. pack the bore with dry ice while you heat the sleeve with a propane torch.

Or just put the assembly in the freezer overnight, take it out in the AM and heat the outside with the gas and it might expand the sleeve enough to loosen it before the heat conducts through to the casting.

Quick and dirty – cut a diagonal slot through the sleeve and expand it for easier removal, or grind through the side of it with a Dumore (Dremel) grinder.

You can probably also chuck the housing in the lathe and machine it off but you’d need a good sized lathe and four-jaw chuck or faceplate to make that one work.

Lotsa ways to skin the cat.

PM T2
May 25, 2018 at 12:37 pm #76697
Buccaneer
Participant
US Member
Heading out to the garage now to look it over and come
up with a battle plan. First plan of attach will be to
set up a fan in the garage and douse myself with OFF…..
Mosquitoes are vicious, and it’s way too hot and muggy
in MN for May.
Thanks for the ideas.

Update- Sleeve came off the post. Ended up using
a cutting wheel in an air grinder. Tried a torch
and pipe wrench first, then my bearing puller to
no avail.
Lo and Behold, the Speeditwin mag plate fits
on the post now!

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May 31, 2018 at 2:34 am #77108
hans
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US Member - 2 Years
the annual bonus for PMT2 is, in reality, the high regard he is held in by so many of his beneficiaries of his helpfulness.
Hans
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