Aerotec transom splash issue.

[Locozodiac]

Yes, have seen such behaviors in other standard Sibs with alum floors, rear fabric not stretching as a drum right at the begining of the lower transom area and producing excesive water turbulence against lower leg and prop as well.

It's good to know that you guys are fully aware of the lower leg height differences between outboards brands and how difficult is for each one to match the perfect sweet motor/transom height to power any Sib correctly to get the max out of each combo.

If you need to choose a set distance between upper and lower plates from pic in order for a flat water flow to skim by nicely while exiting under middle hull, which distance say upper, middle or lower leg height would you choose and why ?

Max, nice water deflector plate you built on your motor's lower leg to cancell the awful disturbed water splash coming under the aerotec's middle transom, did you tried a much smaller size, if so, how did it worked out.

Happy Boating

[Gazzago]

Here’s another of Al’s video after his transom mod. This one is a 15hp Mariner. 50 sec video.

https://youtu.be/dPPI5kGoW8s

[Fenlander]

Thanks for uploading that Gazza... that's a very tidy wake for an Aerotec/Mariner 15 combo.

[Locozodiac]

Originally Posted by Gazzago

Here’s another of Al’s video after his transom mod. This one is a 15hp Mariner. 50 sec video.

https://youtu.be/dPPI5kGoW8s

Nice lower leg behavior, what was done? Assume one of 3 :

-The lower hull fabric near lower transom has been re worked to be flatter ?

-The motor was raised, shimmed accordingly with motor trim set at 90º ?

-Added a secondary water deflector plate same as Max's posted picture ?

Matches same water behavior seen on the Sea Max 430 Sib/ 2 stroke 30 HP motor/ modified motor/transom height.

Happy Boating

[Big Al C]

reworked bottom edge of transom and floor to give a near 90deg trailing edge.

[Fenlander]

>>>Nice lower leg behavior, what was done? Assume one of 3 :

No need to speculate or assume... just read post #85.

[Locozodiac]

Originally Posted by Fenlander

>>>Nice lower leg behavior, what was done? Assume one of 3 :

No need to speculate or assume... just read post #85.

With Big Al C answer would have been enough....

Happy Boating

[Fenlander]

>>>With Big Al C answer would have been enough....

Maybe... or maybe not...

Varying degrees of transom splash have been a big feature of Aerotec ownership for many as this 127 post thread going over 3yrs shows. Big Al has taken Chipko's idea and had the confidence to put it into practice modifying a fairly new boat.

In asking him what he'd done it showed you hadn't seen his modification images which are on that post #85. They are worth seeing as it's a great piece of work which massively reduces the problem.... hence me giving you the post number so you didn't have to look right through.

[Locozodiac]

Thanks, have read both Al's and Max's solutions to address nicely that unwanted back splash issue. We're dealing with non flat hardened water flow exiting out transom. When sitting any motor on transom and afterwords going for a wot spin, most times will find that there's a mismatch between transom height and motor brand powering your boat.

Have Aerotec owners tried to play with motor/transom different heights while motor was trimmed to 90º before going for Al's and Max's solutions ? share your experience.

Happy Boating

[Fenlander]

>>>Have Aerotec owners tried to play with motor/transom different heights while motor was trimmed to 90º before going for Al's and Max's solutions ? share your experience.


Chipko has in post #34 & #48... Big Al in post #58... and myself in posts #69 thro #73 plus post #81.

It's one of the interesting aspects of Aerotec ownership and an aspect I'm delving back into with a possible outboard change.

[jeffstevens763@g]

The beauty of this thread is that everything has been explored re engine position before splash guards went some way to controlling the splash Big Al has gone for redesign which has transformed the hull as it should be from the manufacturer not easy to start glueing bits on to your pride and joy in the hope you got it right

[69cmw]

Originally Posted by jeffstevens763@g

The beauty of this thread is that everything has been explored re engine position before splash guards went some way to controlling the splash Big Al has gone for redesign which has transformed the hull as it should be from the manufacturer not easy to start glueing bits on to your pride and joy in the hope you got it right

Well said [emoji108]

[69cmw]

Originally Posted by Fenlander

It's one of the interesting aspects of Aerotec ownership and an aspect I'm delving back into with a possible outboard change.

Another engine Fenlander [emoji41]

[Fenlander]

Yep seems so. Too complicated to explain on this thread but needs, wishes and aspirations have aligned to pull us back to a post 2000 15hp 2-stroke. A potential buy is on the cards and if it works out I'll chuck a post up.

[Big Al C]

nothing is do with a tidy wake for an Aerotec/15 combo?

[Fenlander]

After my transom lift late last year... not so far off the job you did to yours... the wake/splash was near enough. But I realised the sweet spot for me in power vs portability was 36kg and 15hp... which equates to a 2-stroke. So full circle I go to where I was when we first bought the Aerotec.

[Big Al C]

Originally Posted by Fenlander

After my transom lift late last year... not so far off the job you did to yours... the wake/splash was near enough. But I realised the sweet spot for me in power vs portability was 36kg and 15hp... which equates to a 2-stroke. So full circle I go to where I was when we first bought the Aerotec.

I'm the same... looking at selling the 25/30hp 51kg and using the 15hp I picked up last year and haven't used yet..... should never have sold my other some years ago.

[69cmw]

Originally Posted by Fenlander

Yep seems so. Too complicated to explain on this thread but needs, wishes and aspirations have aligned to pull us back to a post 2000 15hp 2-stroke. A potential buy is on the cards and if it works out I'll chuck a post up.

Like this [emoji41]

[Fenlander]

Ha well that's what I had and I did make gentle enquiries to buy mine back with no luck... but I'm looking at another make currently. I'll say no more as I don't like to tempt fate until the money is handed over and the OB in my garage.

[Locozodiac]

Originally Posted by Fenlander

Ha well that's what I had and I did make gentle inquiries to buy mine back with no luck... but I'm looking at another make currently. I'll say no more as I don't like to tempt fate until the money is handed over and the OB in my garage.

Why don't you look for a 2 strokes short shaft Tohatsu 18 HP to power your Aerotec 380 Sib. Sits top in the 9.9-15 HP portable range. Will power nicely anything that floats...

Happy Boating