Mercury Mark 15 Timing

[Bob Foscato]

How does one set the timing on a 1951 Mark 15?

The timing moves as the throttle advances, one assumes that the points should open somewhere around 20 degrees before TDC on number one cylinder, but without a mark on the flywheel how does one know for sure when the points open at full speed?

[dave-bernard]

Just set the point at cam top don’t worry about the timing just the point gap.

[seakaye12]

Dave and Bob;  What is the story with the mark 15?  Is it essentially a KH7 with a remote tank and different cowling?

Bob….can we see a picture of your motor?

[Bob Foscato]

Please Excuse the old coils and condensers, those have been replaced.  Yes, it is probably similar to a KH7 of which I have not work on either,

This motor as you advance/retard the carb’s throttle,  it also advances and retards the timing via two gears.   You can change the position of the timing by the placement of where the gears mesh.  I basically closed the throttle down and that is where I placed  the beginning of the advance.  I could very well place the gear so it is at the furthest advance when the throttle is fully open and the gap of the points are fully open and the Piston is just before TDC (perhaps 20 degrees).

There must be a procedure and timing plate/tool to set the timing correctly.

[Buccaneer]

I would think there’d be something in a manual regarding sychronizing
the carb to the magneto.

Prepare to be boarded!

[seakaye12]

Here are a couple of pages from my manual.  It says Mark 25 but also applies to Mark 15 and 20.  Sorry for the marginal quality.  It does address the setting of the gears you talk about….

Maybe your Mark 15 has a stop on the mag plate that limits maximum advance?  If not that can be set as well.

• This reply was modified 2 years ago by seakaye12.

[Buccaneer]

Found this, hopefully there’s something in it that will help.

Prepare to be boarded!

[seakaye12]

Here are a couple of pages talking about using the timing tool.

[Bob Foscato]

Thanks, I’ll study the procedure and look for a timing plate and indicator arm.

[crosbyman]

deleted like the old coils 🙂

Joining AOMCI has priviledges 🙂

• This reply was modified 2 years ago by crosbyman.

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