Outboard bracket installation

[Guest]

Hi All

 

I need your feedback and guidance for outboard bracket installation. Please share your lesson learned from previous experiences.

 

In the attachment, I've included a diagram to help with the visualization.

 

Measurements are:

A: Shaft length - 508 mm (20inch)

B: Exposed shaft length -

C: Submerged shaft length -

 

What would be the optimum submerged shaft length?

I don't want to go too deep so that there's not enough clearance for the waves or in hobby horse motion. But it needs to stay deep enough for efficient propulsion.

 

 

There are a number of different types of brackets available. What is your recommended bracket?

Here are few links:

 

1. http://www.burnsco.co.nz/ProductDetail?CategoryId=220&ProductId=543&Colour=0000000136

2. http://www.burnsco.co.nz/ProductDetail?CategoryId=220&ProductId=1320&Colour=0000001827

3. http://www.smartmarine.co.nz/products/engines-accessories-steering/outboard-parts-flushing/59413/alloy-rise-fall-transom-mt-auxillary-outboard-moto/details/

4. http://www.trademe.co.nz/motors/boats-marine/parts-accessories/other/auction-659033207.htm

 

I like 4 for its angle adjustment. 3 seems be nice and compact. 2 is most expensive but most durable and heavy duty.

 

What wood do you use for the angled bracket backing? Marine plywood? Any other idea for angled backing?

 

Thanks,

[Guest]

You could always look for work as a graphic artist

[banaari 27]

I think I'd want to inspect those in person - some of that folded stainless steel stuff looks disturbingly flimsy, although it could just be the photos.

All things being equal, something with the biggest possible footprint where it attaches to the transom - spread the load as wide as possible.

[Adrianp 120]

What size and weight outboard are you putting on it?

 

Most of those would be OK for a 5-8hp 2 stroke) but if you going any bigger option 2 would be the only one I'd use. Try the maker for a better deal - http://www.tenob.co.nz/shop/Outboard+Motor+Mounting+Bracket/Auxiliary+Motor+Brackets/Adjustable+Motor+Brackets/25hp+Stainless+Steel+Transom+Fit+Rise++Fall+Bracket.html

 

You definitely get what you pay for with outboard brackets. Those cheap ones are just flimsy finger traps! They also usually have crap springs which means you do all the lifting - from a precarious position on the stern when you have no leverage.

 

Also look for alloy/stainless contact corrosion points on these things.

[banaari 27]

Looking at a choice between the crap or horrendous expense of a replacement I'm suddenly very fond of the one I've got, although it needs some TLC.

Any idea what wood is/should be used for the motor clamp pad?

[Guest]

High'n'Fibre: I am thinking about 4 stroke 6hp Yammy for my S&S 24 falcon (displacement 2 ton). The outboard weighs around 27kg.

Crew Ogre: somehow whenever a new boat project comes to me my creativity instinct come to life. I think I gonna frame it up. lol

 

a bit of research last night, I found that the manufacturer's recommended length for transom height is 20 inch. That means "A" length should be equal to 20 inch.

Does this mean that the outboard performs best if the hydrofoil is just below the surface? But if you consider vertical movements of the boat, the propeller will expose to the air. For yacht, I would thought it's better to be go deeper and propeller stays in the water.

 

Any thoughts?

[waikiore 403]

Pushing a yacht you must use the heavy duty Tenob rise and fall bracket, that's what I use with a 25' Yacht and 8HP long shaft Honda, (with doubled up springs as its over 50kg) Make sure that you have decent size penny washers on the inside too. The cavitation plate must always be under water-- yes in a seaway or you will have big problems going forwards upwards of 25 knots.

[rigger 47]

Any idea what wood is/should be used for the motor clamp pad?

 

I used two pieces of 18 or 20mm Marine ply laminated together, it was what had been there in the past. I did think of laminating hardwood strips on where the clamps contacted but never got around to it. I did make it a bit wider at the top to make it easier to land the outboard on before adjusting for the final position.

[Zozza 293]

I got one of these: http://www.garhauermarinehardware.co.nz ... otor-mount

Rated to 57kg, and $200 cheaper than the Tenob.

I am yet to install it, but it is a serious bit of kit, and should handly your outboard for a &S 24 no problem.

[Changed 10]

Remember to check what you're bolting the bracket to. Most fibre glass boats need some strengthening in the laminates to take an outboard bracket. You can usually recognise the tell-tale gelcoat cracks if it's not strong enough.

[Island Time 1,240]

When replacing the timber, consider plastic. Like a plastic heavy chopping board. I use a white one, never needs painting/varnish, looks good, pretty permanent, tougher than timber.

[DrWatson 381]

Any idea what wood is/should be used for the motor clamp pad?

 

any good hardwood with interlocking grain...

 

Up where you are you might find a piece of Puriri (firewood) and plane it up to fit. It's tough as iron and heavy as hell.

Great stuff.

[DrWatson 381]

When replacing the timber, consider plastic. Like a plastic heavy chopping board. I use a white one, never needs painting/varnish, looks good, pretty permanent, tougher than timber.

 

True, those nylon chopping boards make great stock for all manner of things. terrible chopping boards though...

 

R