Delta Project - part 2

gohelm · 22 July 2011, 16:44

As some of you have been reading, I / We am/are all set to go for another conversion of our 6.8m Delta Rib.

After last winter's refurb on electrics, tubes and console we used to boat for half a year when we decided that the boat is VERY fine but that the Hamilton / Yanmar combo , although great on the North Sea, is not so well performing on the Ijsselmeer in the Netherlands, where shorter waves are resulting in frequent cavitation issues at exactly the wrong moment. We are seriously regretting removing the waterjet since it really has its advantages but ‘in the big picture’ we feel that the outboard will be just better for our use (the boat is used 90 percent of the time at the IJsselmeer). It always has been a calculated risk that the inboard/waterjet wasn’t to our liking when we bought the boat in the first place.
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Therefore conversion part 2 will about removing the Yanmar engine and waterjet and converting it to an outboard engine.

We found via a dealerfriend a neat, nearly new Suzuki DF250 XU to hang at our transom and the plan is that in the next 2 weeks the yanmar inboard will be removed, the floor will be mad flush and the bottom will be made suitable for attaching an outboard plus the fuel system will be amended for petrol use and we intend use that configuration for the remainder of the season. The experiences during the remainder of the year will be used for the rest of the conversion, which includes a seating upgrade and some works at the transom (I want a storage at the stern and a waterbarrier type of construction to avoid un necessary wet feet) and this conversion/upgrade we intend to perform winter 2011-2012.

In the mighty collective experience on this forum, are there any opinions, suggestions, comments (good or bad) , ideas, ‘now you are at it would you consider.. etcetera’ moments you are willing to share?

Thanks beforehand!

gohelm · 04 August 2011, 14:03

It feels a bit awkward to put your boat in a workshed right in the middle of the season, but on the other hand it is an excellent time of the year to apply polyester temperaturewise and with no sailing events scheduled, we wouldnt have used the boat that much anyway.

the 4LH Yanmar was out in a couple of hours, so was the hamilton and all the cabling.
Removing the engine cover proved to be a bit more tricky, especially since the cover alone weighs around 85 kilograms.

For tonight we have planned to drain the tank of remaining diesel and clean it up.
The boat has a date with 'tall suzy' end of week 33, so in the next week there are some holes the engine/jet left, which need to be plugged and made 'flush' and there is a new floor to be inserted in the former engine bay.

For that - luckily - we will have some assistance from a local polyester boatbuilder who is sharing some expertise ...

Will keep you posted !

gohelm · 08 August 2011, 12:33

reckon that a good bilgepump will cope with this ;-)

gohelm · 19 August 2011, 13:13

With all holes plugged the boat is in living up again with the expectations we had on her, like providing us dry feet for example...

Although the transom seems sufficiently sturdy to support a 270 kilo outboard, we decided to add some reinforcements (vacu full glass stringers, laminated to hull and transom), it is a small piece of extra work now and we had nothing to loose by adding it.

We also added 2 additional frames in the former engine bay to support the deck and for additional stiffness of the boat. The space left below the deck will become a double locker (used but good watertight hatches.... anyone?) with the very aft compartment dedicated to batteries, electrics etcetera.

The outboard is ready to be placed and same will happen this sunday - pictures will follow!

gohelm · 28 August 2011, 22:21

Engine installed.... The 'flattened' last 30 cm of hull makes it a lot easier to use a single engine instead of twins...next station : flooring and seating!

CJL · 28 August 2011, 22:31

Keep up the pics, its looking very good!

Chris

gohelm · 11 September 2011, 21:15

Trial floor and 1st seatrials...

I am happy with an easy 43 knots (5400 rpm) although there seems to be some room for improvement (not sure if i really need the addintional 4 knots or so versus the extra stresses on the engine/transom).

Also i am still considering a 'transom box' (for storage and to prevent the wash rolling in from the stern) but the first experiences with the xu shaft suzuki(77 cm) is that the transom has sufficient freeboard anyway and the present hatch for batteries, mains and filters plus an additional one for storage we reckon will be sufficient....For 'water issues' a well placed bilge at the stern may suffice. There is a higher and stainless steel flange plus pipe in the making for cabling and hydraulics to prevent water ingress via the cables.

Balance in the boat changed more than anticipated and the bow needs about 50 kilos additional weight - any suggestions?

Our plan with this provisional layout is to try it for the rest of the season and then decide how to finalize the layout plus installing additional seating ( this will cover the fuel lines who are now temporarily covered by a small (but nasty to stumble over) box ) this winter.

Will keep you posted!

Zagato · 12 September 2011, 07:49

Looks great

gohelm · 21 September 2011, 09:28

I have a question with regards to the trim of my boat:

the loss of weight after the inboard came out made her 'trimmed by the stern' too much and i reckon that i need to ballast the bow a bit (40/60 kilos).
would anyone have any suggestions for a good way of doing that? I have a nice anchor locker in the bow but what would be a good way to have no lead and/or other metal bouncing around in the anchor locker?

suggestions, anyone?

cheers, Gabor

willk · 21 September 2011, 10:18

Big bag, full of small bags, full of diver's lead shot (small lead spheres)

diverbert · 21 September 2011, 10:29

Hello Gohelm,

A freind of mine has had the same thing and has put sand in a sandbag under his bow locker. in dutch "hij heeft gestabiliseerd zand in zn locker gedaan en dat blijft goed zitten zonder schade"
Just look at the structure of the boat that you devide (verdelen) the weight well.

groetn
Diverbert

HUMBER P4VWL · 21 September 2011, 13:02

We used to use a sandbag in our old dory (horrid boat) to keep the bow down.

Can't quite see, but another option is to fit a bench or locker in front of the console which could house other stuff that has weight, spare fuel tank, liferaft etc

Re wet feet, really you need to make a well at the rear of the boat for the bilge to sit in.

Nice boat by the way.

gohelm · 21 September 2011, 15:51

Quote:

Originally Posted by HUMBER P4VWL

We used to use a sandbag in our old dory (horrid boat) to keep the bow down.

Can't quite see, but another option is to fit a bench or locker in front of the console which could house other stuff that has weight, spare fuel tank, liferaft etc

Re wet feet, really you need to make a well at the rear of the boat for the bilge to sit in.

Nice boat by the way.

Hi paul

thanks suggestion but i think there will be no room for an additional bench or locker in the bow.

wiik - diverbert(moi!) : Thanks for your imput. I am considering to laminate simple lead pellets with epoxy resin in the anchor locker and then laminate some additional glass on top of it. That way it's kept simple and not bouncing around the boat doing damage of some kind, provided proper prep work prior laminating.

paul ; I agree with the wet feet comment; We had substantial 'stern to wind time' last weekend with short steep waves, resulting in a little swimming pool, and yes i need a lowered bilge of some kind plus a construction of some kind at the lowered transom to prevent water ingress via the stern.

best regards
gabor

Erin · 21 September 2011, 18:41

You say you have the battery in your new stern locker. Would it not be possible to move this forward to the console. Losing 25kg at the stern and gaining 25 near the front would be almost the same as putting 50kg in the bow locker.

HUMBER P4VWL · 21 September 2011, 20:09

Great point re batteries. Don't most large 2strokes have 2 batteries too? We do.
May also be best to have them in the console raised above the tube line/water line if swamped. Many a waterproof hatch isn't waterproof when swamped!

gohelm · 22 September 2011, 07:09

Quote:

Originally Posted by Erin

You say you have the battery in your new stern locker. Would it not be possible to move this forward to the console. Losing 25kg at the stern and gaining 25 near the front would be almost the same as putting 50kg in the bow locker.

Good point , however the battery placement is a heritage of the old inboard engine. Repositioning implies a lot of rewiring however will investigate!

gohelm · 22 September 2011, 07:21

Quote:

Originally Posted by HUMBER P4VWL

Great point re batteries. Don't most large 2strokes have 2 batteries too? We do.
May also be best to have them in the console raised above the tube line/water line if swamped. Many a waterproof hatch isn't waterproof when swamped!

Have 2 optimas in the back both are still heritage of the inboard. Having separate juice for (4stroke) engine and for board electrics is very convenient - the present hatch is very waterproof when swamped but will be likely (depends on if moving batteries forward as erin suggested) replaced by a freeman hatch (i'm a bit paranoia on having water in the hull)
With 2 x 2 sets of radio's in the console plus a number of other gizmo's in it, the console seems not the ideal place for the batteries. plus putting 30 kilo of material that high will not help keeping center of gravity low as possible and deadscared they will start cruising aroundover there.

gohelm · 24 December 2011, 22:48

An update on works on the boat after using the outboard for half a season:

The 2nd jockeyseat takes shape (although longer than the forward one, since it needs to cover both fuel lines and tank hatch) and so does the new flooring and bilge. We changed the gps to a flushmount on top of the instruments (which layout not finished) . The hatches (they are perfect for the job Chubby, thanks!!!!) include a double locker under the floor (which is in fact the former engine bay). Also some changes to the radio's I but will get to that later... Happy Xmas to you all!!!

Oscarguitar · 28 December 2011, 18:00

Hi, I might be way off beam, but with a long shaft motor you could be running with the engine too low. (looking at the build pictures seemed to confirm this but is it hard to tell) This will but extra strain on the transom and increase bow lift and drag while reducing economy and top speed.

Take a look at this article,

Propping correctly & how to test props.....

Apologies if you are already miles ahead on this one but is seems a shame to add weight or move things around when lifting the motor a couple of holes could make all the difference.

All the best

Oscarguitar · 28 December 2011, 18:03

Sorry another thought, a stern lifting prop such as a 4 blade Rev 4 could also make a big difference to the trim and allow you to plane easier and at lower speed.