Ski Twin 33

For pre 1975 outboards and race motors only.

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Rapier
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Re: Ski Twin 33

Post by Rapier »

Nice one. At this rate you'll have it ready for the next I&S run.
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water_buoy
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Re: Ski Twin 33

Post by water_buoy »

Rapier wrote:Nice one. At this rate you'll have it ready for the next I&S run.
:? Not sure about that, lots of tedious painting to do yet, I hope it will make this season though :wot:
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water_buoy
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Re: Ski Twin 33

Post by water_buoy »

I had a quick trip to Reading today to collect a Johnson 33 from Duncan Walker outboards :chuffed: on recommendation from Geoff and Phil at the weekend (Phil's old engine) this will now be taking up place on the boat and the ski twin will become a doner :D

Plans are to pinch all the electric starting parts of the ski twin as the Johnson is manual start :heat:

I will the continue building up the head which I have already started so I should end up with a complete spare power head which I would say is almost as good as having a spare engine, but a heck of a lot lighter to carry around.

Anyway I have a bit of transom reinforcing to do this week so with a bit of luck I might have it on by the weekend :woo: ... pics will follow!
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Alacrity
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Re: Ski Twin 33

Post by Alacrity »

That is good news Dan, no more bringing up the rear for Lady S! :wot:
Mercs are like women, no 2 are exactly alike. That's what testing is about. In general it is safer to test motors and props than women!

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water_buoy
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Re: Ski Twin 33

Post by water_buoy »

Quick trial fitting today just to see what it looks like before I fatten up the transom a bit :chuffed:
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LitchboroughLitchbor
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Re: Ski Twin 33

Post by LitchboroughLitchbor »

Any tips on fitting new piston rings to these older OMC engines?

I've been practicing on a little 6hp, before moving onto anything more valuable. Aligning the piston rings to the little lugs in the pistons seems quite fiddly. Very easy for the rings to slip past the lugs, causing the rings to bulge.

After a lot of frustration and a few broken rings, I've found that a jubilee clip and a sheet of transparent plastic, from a stationery folder seems to work. I found a good video on YouTube. The only drawback I've found with this approach, it to avoid the plastic pushing into the bores and jamming.

Through the clear plastic, you can actually see the lug and ring ends lining up as you tighten - in a way your probably couldn't with a metal automotive ring compressor. When the ring ends do slip past the lug (as they often do) it's just a case of loosening off and trying again.

But perhaps there are other approaches?

I'd be interested to hear.

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