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Old 02 February 2016, 18:50   #11
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Country: UK - Scotland
Town: Aberdeenshire
Boat name: Sula
Make: Ribcraft 4.8m
Length: 4m +
Engine: Tohatsu 60hp + aux
MMSI: 235087213
Join Date: Jun 2007
Posts: 3,270
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Speaking of old 2-strokes...

Occasionally Yamaha 50hp long-shaft 2-stroke outboards come on to the market. In this case (if the seller is to be believed) as part of friend's estate.

The Yamaha 6H4 40hp and 50hp are arguably the finest 2-strokes ever built, and if you're lucky enough to have owned one (I had a 40hp on a Zodiac Pro) you'll never look back. They use 3-cylinder blocks, and if well maintained will serve you well.

Ignore the seller's grossly inaccurate weight calculation. These engines weigh approximately 70kg+ depending on model.

You could always reinstate the transom to full height if you're handy, or ditch the 4-stroke.

Yamaha 50HP Outboard.. | eBay
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Old 02 February 2016, 22:23   #12
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Country: USA
Town: Connecticut
Make: Zodiac
Length: 6m +
Engine: Undecided
Join Date: Nov 2009
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I 've run a number of Searider 4m with Honda 40 hp four strokes with no issue at all.
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Old 03 February 2016, 06:25   #13
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Country: Ireland
Town: Cork
Boat name: Excalibur
Make: Excalibur + Zapcat
Length: 6m +
Engine: Merc120TDI,Tohatsu50
Join Date: Jun 2005
Posts: 245
An easy fix I have on an old Cobra that was never designed to carry a 100 hp four stroke is a pair of thick rubber flaps cut to closely fill the gaps in the transom. I'm talking about 15-20mm thick rubber. They're screwed to the outside of the transom and have enough "give" to allow the engine pivot and the trim to work fine. They're not 100% as good as a raised transom but I was amazed at how effectively they'll keep water out while drifting in chop or stopping suddenly.

In second place, I've seen some RIBs fitted with a GRP well inside the transom that's big enough to clear the engine swinging and tilting that simp,y funnels the water back out the low transom. I helmed , I think a Delta ( they never had much buoyancy at the stern, especially with a bunch of divers gearing up), years ago that had something like a heavy piece of tarp made on to a S/steel frame to form a similar inboard well. Looked jury rigged but worked for years. Maybe a cutout fertiliser sack, a broom handle and some double sided tape might allow a proof of concept test?

In third place I've a Ribtec that had the transom reinstated by a very substantial piece of sheet S/steel folded into a "U" to neatly fit over the transom and bolted on. The engine at least the top two bolts is secured to that doubled over plate. Reinforcing plates are common on RIB transoms but this is the first one I've seen making up the transom and it works a treat both structurally and to keep the sea where it belongs.

Cautionary notes are if you go with a solution that leaves the engine at its current height I never leave my engine off and down if drifting in chop as the lower exhaust port could allow seawater wash up into the lower cylinders. I know that happened on at least one F115. So beware mooring if the stern could be presented to chop.

If on the other hand you go for raising the engine/ transom, check first where the cavitation plate will sit first.

Whatever your solution, be aware the boat will be tail happy heading into waves, use caution in steep waves or where you risk getting air even -at sub planing speeds. Get the battery and fuel tanks as far forward as you can and carry spare fuel, anchor, dive weights etc in the bow.

You've a nice package, work on getting it optimised rather than filing for an expensive divorce!
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Old 03 February 2016, 06:33   #14
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Country: Ireland
Town: Cork
Boat name: Excalibur
Make: Excalibur + Zapcat
Length: 6m +
Engine: Merc120TDI,Tohatsu50
Join Date: Jun 2005
Posts: 245
"But that will probably have minimal impact on "pooping" (when your stern wash comes back over the transom after you stop."
That sounds messy Poly. I've had a few scares at sea but I'll only admit to almost pissing myself. You make a strong case for never tucking your pants into your sea boots☺️
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