Outboards permanently fitted to SIB's

Clipper · 02 May 2010, 04:00

Hi all,

looking for a definitive answer to a question I have asked before, and also asked numerous SIB suppliers.

Is it okay to have an outboard permanently fitted to a SIB on a trailer?

1st scenario - 3.4m Quicksilver hypalon, with a 18hp 2 stroke?
2nd scenario - 3.8m Quicksilver duratex, with a 25hp 2 stroke?

the answers have ranged greatly from; yes not a worry, yes only on 3.8m+ SIB's, to no SIB cant handle outboard weights, to the glue joining the transom to the boat material will give way etc.

Is there an answer to this riddle? whats the difference for a boat bouncing in the water with an outboard to a boat bouncing on a trailer with an outboard?

many thanks in advance

treerat · 02 May 2010, 08:22

Not sure if it's definative for you but I had a Yam 3.83 sib with a 25hp on it for 7 years. I used to store the engine in the garage but traveled with it attached with the boat on a trailer.

The current owner stores it attached and it hasn't been off in 2 years.

Still looks good as new.

C2 RIBS · 02 May 2010, 09:43

I also had a quicksilver with a Mariner 25 fitted permanently to the transom with also and A Frame and all on a trailer set for this boat and never had any problems.

chris123 · 02 May 2010, 09:47

Sadly, I think you may struggle to get a definitive answer.

I think the difference between afloat and on the trailer is that when afloat the hull is completely supported and the engine is down. When on the trailer with the outboard up there could be more leverage on the transom, potentially with more of a twisting moment if the outboard is tilted up (outboard down is better).

For what it is worth, I trailer my SIB with the outboard fitted, however it is a very heavy duty SIB, and my trailer includes a support underneath the skeg of the outboard (an arrangement that will probably divide opinion as much as the whole outboard fitted or not argument

)

Cheers

Chris

Clipper · 02 May 2010, 10:58

thanks guys,

precisely the info i was looking for, long term use of SIB and outboard on trailer without significant trouble or issues.

looks like i might even put the old 18hp on my 3.4m without stressing.

chris, interesting setup, looks like a bit of planning can go a long way.

cheers guys

m chappelow · 02 May 2010, 15:15

A lot depends on how far you are going to tow and what condition the road is ,,holes bumps ,,and how your boat rides on the trailer ,eg does it bounce ,most times ,i personally put my engine in the boat layed down flat .

i have noticed though that with my trailer,,,and i can put the boat on both ways ,,as it doesent have a front post but if i dont pull it on far enough the engine will bounce bad even a foot or so can make a big difference,

i suppose a lot depends how far back the wheels are fixed to the trailer ,,most boats that i know with a fixed bolted through transom engine have the wheels nearly at the end which stops most of the bounce ,see/saw or pitching of the outfit.

ooglewoogle · 02 May 2010, 16:19

Quote:

Originally Posted by chris123

however it is a very heavy duty SIB

What make of SIB is this Chris (sorry, newb. here!)...it looks mighty.

chris123 · 02 May 2010, 16:43

Quote:

Originally Posted by ooglewoogle

What make of SIB is this Chris (sorry, newb. here!)...it looks mighty.

It is an ex RNLI Y boat, used by the RNLI as a daughter boat on Severn class and Tamar class lifeboats.

Basically it is a beefed up 3.5 metre Avon SIB.

Cheers

Chris

nice.diver · 03 May 2010, 00:09

it takes me over an hour to remove my remote steering johnson 40 off my 15 1/2 ft zodiac, its not comming off to store or trailer the sib

jyasaki · 03 May 2010, 07:56

My Achilles 14 spent the 4 or 5 years I had it on the trailer with a Honda 40 honging off the back. It was trailered on a 200 mile round trip about 3 times a month on average, and never showed any sign of stress at the transom joint. I did use a transom saver when trailering (along with something to tie the thing from swinging as it was tiller steered); just put the motor up on the tilt lockout when in storage.

I see the boat every now and again in Monterey; aside from a patch on the tube from a wayward nail on a dock somewhere, it appears to be holding up well.

jky

Clipper · 03 May 2010, 08:08

fantastic info, my SIBing has just taken a turn for the better. I can honestly say I was entirely over dismantling the boat after a dive, and was considering giving it up. I was almost considering an aluminum substitute...I know its blasphemous.

Happy to tie the outboard down so that it doesn't swing during transit.

cheers guys