Timing marks 1955 Bigtwin

[hmai]

Guys I have a 1955 Johnson Bigtwin, when started it runs really well and idles to a near stall, but a little hard to start when cold. ( 5 or 6 pulls). Sometimes its hard to start when it stalls from a low idle (every great once in a while). I wanted to fine tune the ignition but only see the marks on the magneto plate. Where can I find the timing mark on the flywheel. Obviously I do not have a timing fixture which are becoming impossible to find, but thought the flywheel has a mark.

Some help would be appreciated. I have several 7.5s that almost always start on 1st pull. Or am I chasing the wrong problem?

[RICHARD A. WHITE]

I have found advancing the timing a bit on initial startup helps…..Some have a tendency to start them not advanced enough

http://www.richardsoutboardtools.com
classicomctools@gmail.com

[chris-p]

Well I don’t know, to start, im assuming you are using the choke, and it is fully closing, on cold starts?

Frank makes timing fixtures, and they are fantastic.

http://www.franksoutboardtools.com/

What is the compression?

Spark jump a 1/4" gap with a bright blue SNAP!!?

To set the linc n sync, use the fixed pointer to the left of the roller, not the roller.

[frankr]

Nearly sold out, and going fast.

[1946zephyr]

The timing varies, each time you twist the throttle. What do you mean by "setting the timing?" It’s not like the distributor on a car. The throttle linkage does have to be in sync with the mag plate though, or you’ll tire yourself out trying to start it. 😉
The correct point gap will determine the correct time for the points to close, though

[RICHARD A. WHITE]

quote 1946Zephyr:

The timing varies, each time you twist the throttle. What do you mean by “setting the timing?” It’s not like the distributor on a car. The throttle linkage does have to be in sync with the mag plate though, or you’ll tire yourself out trying to start it. 😉
The correct point gap will determine the correct time for the points to close, though

Can’t say I agree with this… Actually it is like setting the timing for a car. Franks tool, as well as the OEM tool, set the points to break at the optimal time, for arguments sake, lets say 5 degrees BTDC. Just setting the gap, by itself, only gets it "close enough" for the average Joe. You could easily be off by 2 or even 5 degrees, which will still allow the motor to run, just not as good as it could
This has been discussed at length in previous posts. While just setting the gap will work, for insanely slow idle, only the timing tool, or just plain getting luck will do it.
I had a timing degree "wheel", a piece of paper with 360 lines around the perimeter, that slipped over the mag, when setting the timing, using just the points method, then checking with Frank’s tool, I was 3 degrees off. that will clearly effect the performance of the motor, and yup she ran…

And I must confess, I say this with the utmost respect for your knowledge.

http://www.richardsoutboardtools.com
classicomctools@gmail.com

[chris-p]

You are both right, sort of.

The "timing", as we know it is fixed. Hence the flywheel key. The timing cannot be altered on our outboards.

However, the points timing can. As Richard stated, the points gap is just a means for the average joe to set them. By far the best means is a timing fixture and buzz box if you have one.

[Mumbles]

The static timing is set by the width of the points gap. Once the motor is running, the degree of spark advance is set by the rotation of the mag plate which is controlled along with the amount of carburation by twisting the tiller grip.

[hmai]

Guys thanks for the help. Ignition timing is critical and makes the difference between a ok running outboard and one that purrs. You will not get this from simply setting the gap, why else would they have timing marks. I did find the timing marks on the flywheel and believe the ignition was slightly late, hence the hard starts. (Although it was gapped correctly) I expected them to be a little more obvious. I am sure Frank’s tool is great, but for now pulling the flywheel off and on to tweak the points is just as good especially since I simply do not mess with many of these. Now I have no doubt it will start a little easier.

There’s is no better feeling then your 60 plus year old outboard running as well if not better than the brand new motor next to you. This old bigtwin definitely gets some looks.

[Mumbles]

quote Hmai:

There’s is no better feeling then your 60 plus year old outboard running as well if not better than the brand new motor next to you. This old bigtwin definitely gets some looks.

You sure hit the nail on the head with that statement! I have to agree it’s a good feeling when you are at the ramp with your classic getting all of the attention while the guy next to you with his heavily financed Yamazuki seems kind of lonely! It’s a good ego boost! 😀

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