Ski Twin 40

For pre 1975 outboards and race motors only.

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Rapier
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Re: Ski Twin 40

Post by Rapier »

I think I've got it nailed, but need to test the fixed jet carb to eradicate any doubt. I downloaded and looked at the '51-63 Gale manual first to see if the needle was similar; then bought the '71 Manual online (which covers the BigTwins too). Low speed counterclockwise adjustments are 1&1/4, high speed 3/8...this differs from the conventional Seloc/Clymer/early OMC manuals with a high speed needle which has a primary setting of 3/4 to 1. It may not seem a lot, but at 3/8 it's just off seating (is the correct needle though not shown as such in the exploded diagram). The difference in setting would account for the rough (non idle) running and fouled plugs.
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Rapier
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Re: Ski Twin 40

Post by Rapier »

Beautiful day down here - binned the new Champion J4Js and replaced with NGK B6S, took the boat to the workshop, launched it tied to the trailer, with test prop on and it all worked, finally!! Flat out on the slipway. followed by 6knots upriver to Botley. 11pitch too fine and 25mph, 13 pitch was slipping on the hub now in the bin, but was close to 30mph. Followed by lunch at the Jolly.

Here endeth the trial. :thumbsup: :wot:
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water_buoy
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Re: Ski Twin 40

Post by water_buoy »

:woo: :chuffed: :wot: :chuffed: :woo:
Nice one! Are you taking it out on the next itchen run?
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Re: Ski Twin 40

Post by Rapier »

water_buoy wrote:Nice one! Are you taking it out on the next itchen run?
I'd like to get my '60 Mercury 400 on it for Cardiff, as that needs to be run, so not sure...torn between the two as it needs some hours put on it.
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