Clamping on a small outboard?

Simon Guest · 07 February 2006, 22:23

I'm just downsizing from a rib with a permanently attached 60HP outboard, to a little Zodiac inflatable with a 15HP Mariner 2 stroke, which comes with a bracket to clamp onto the transom. Fairly obvious and unsurprising.

However, what surprised me is the Mariner owner's manual, which says (and I quote): "The use of clamp bracket handles alone is insufficient to properly and safely secure the outboard to the transom. Attach outboard by drilling holes through transom and secure using bolts, flat washers and locknuts provided with outboard."

What???? Is this just some Mariner lawyer giving me a formal warning which I should read and ignore at my peril? Does anyone actually bolt small outboards onto small inflatables?

And how tight do I clamp the thing onto the transom anyway? As tight as I can with my bare hands?

cheers,
Simon (ex RIBster, new SIBster, more questions coming, I'm sure of it)

Poly · 07 February 2006, 23:34

not just a Mariner Lawyer - but Yamaha too!

I have a Yam 20 which said something similar. My boat is not "inflatable" so the engines stays permanently on the back so I chose to bolt it on as well as the clamps (as tight as possible by hand). Having had a 2HP vibrate itself loose in 1 day (fortunately tied on) it seemed sensible. Also might stop an opportunist thief as would at least need a 15mm spanner.

Neil

codprawn · 07 February 2006, 23:47

Had no problems with my 15hp Suzuki clamped to the transom of my quicksilver - even after 20 miles of open sea!!! Just do the clamps up by hand - don't over tighten them either.

If you are worried attach a cable or a bit of rope to the hoop on the transom if there is one.

pathalla · 08 February 2006, 02:10

Some years ago I had a 14 ft Zodiac with a 30 hp Evinrude attached (clamped) did not through bolt it. One fine day we were towing it behind my friend's 32 ft powerboat. Being as we had it on a 150 ft. line, weren't cruising that fast and had the engine tilted up and locked I didn't even think about the motor working loose... WRONG!!!! Only did it about 5-7 miles, the clamps either broke or worked loose, and the rope securing the motor (fuel line as well) did not hold the weight, gone! Dropping a fifteen hundred dollar engine into the drink is a sure fire way to turn a good day into a crappy one! I never even suspected something like that happening. Bolting is good security!

codprawn · 08 February 2006, 04:38

Quote:

Originally Posted by pathalla

Some years ago I had a 14 ft Zodiac with a 30 hp Evinrude attached (clamped) did not through bolt it. One fine day we were towing it behind my friend's 32 ft powerboat. Being as we had it on a 150 ft. line, weren't cruising that fast and had the engine tilted up and locked I didn't even think about the motor working loose... WRONG!!!! Only did it about 5-7 miles, the clamps either broke or worked loose, and the rope securing the motor (fuel line as well) did not hold the weight, gone! Dropping a fifteen hundred dollar engine into the drink is a sure fire way to turn a good day into a crappy one! I never even suspected something like that happening. Bolting is good security!

Yes but that's a bigger engine and when they are tilted up different forces apply.

Hugh Jardon · 08 February 2006, 08:45

on my little quicksilver with a 15 yam i only use the hand clamps and it is fine, in the summer when we are away the engine is connected all the time, it is used a lot of the time every day for 2 weeks at a time and never works loose. i check it every now and then but never needs adjusting, I do however have and engine lockover the handles so they cant turn so maybe this helps.

Noble Marine · 08 February 2006, 10:10

Most smaller outboards I have seen, have holes on the clamp handles for a padlock to be attached. This should be sufficient to deter the opportunist thief and to comply with your insurer's security requests.

As for the outboard working loose - a strap or chain secured to the boat will prevent you losing the outboard entirely and again may be a requirement of your insurance policy.

Simon Guest · 08 February 2006, 19:35

OK, looks like some sort of strap, and possible an outboard lock is the way to go. Thanks for the replies.

cheers,
Simon