Aux Engine Advise

Locozodiac · 21 October 2008, 05:51

Hello...

If you would like to place an aux engine next side to main engine on a complete horizontal 40.5 cm height transom, so no need for lateral jack plate. Do you have to raise main engine from water or simple leave on water in a straight locked position and just steer with aux engine, what would be the correct procedure to do so. Plan to install a Tohatsu 5 Hp next to a 18 Hp on a 380 alum floor sib transom.

Happy Boating

9D280 · 21 October 2008, 10:05

Hi Loco.

I guess your 18 is a tiller control too? if so I'd lift it - all it will do is create drag. I have steered 5+m ribs running with the aux locked ahead and using the main engine as a rudder, but that was more to do with the driving seat being more comfortable than perching on the toob!

Locozodiac · 21 October 2008, 14:44

Quote:

Originally Posted by 9D280

Hi Loco.

I guess your 18 is a tiller control too? if so I'd lift it - all it will do is create drag. I have steered 5+m ribs running with the aux locked ahead and using the main engine as a rudder, but that was more to do with the driving seat being more comfortable than perching on the toob!

Hi 9D280

Yes, forgot to mention that 18 was tiller also, one issue, 5 will not plane the 380 sib, will be useless to put too much power as the sib will have excesive bottom drag including 18 leg & excesive useless bow elevation, the idea is to have the 5 as a pusher (emergency issues) to push sib at low speed to have best horizontal position and the least water drag.

So you recommend to lock the aux and use the main as a rudder. What about locking the main to go straight and using the aux to steer, is there a big diffrence in both steering positions ? As the new sib has not arrived yet, once arrived will be a matter of testing first two positions including main up and aux down too, to evaluate best performance method. Thanks!

Happy Boating

m chappelow · 21 October 2008, 15:05

dont think that the dead 18 wiill give you that much steerage it will probely cause more drag than its worth even in neutral gear think it best to tilt or even take it off and lay it down in the boat that way you might get a better speed out of the smaller engine owing to better weight distibution.its all down to trial and error ,

ruddles · 21 October 2008, 19:10

Hi Loco
Am I missing something here ?

Or, you raise the aux when not in use, if in use, you raise the 18. ?
Have used a yam 2b and towy 18 for years on ribs and sibs. one or the other is in the water.

Works great.

Joe

Downhilldai · 21 October 2008, 21:19

Try it out both ways and see which works best. It really won't take long

Locozodiac · 22 October 2008, 02:21

Quote:

Originally Posted by ruddles

Hi Loco
Am I missing something here ?

Or, you raise the aux when not in use, if in use, you raise the 18. ?
Have used a yam 2b and towy 18 for years on ribs and sibs. one or the other is in the water.

Works great.

Joe

Hola Joe

Just thinking why not use a aux on a new Tohatsu 18, 380 sib alu floor combo, the factory will modify all my future sib's transoms to 40.5 cm, instaead of the actual 38 cm, this will avoid splashing problems with Tohatsu engines, specially the 18 model. Also will place a horizontal straight transom, so plenty of space to play with the aux sideways. Just a matter of waiting till late November to have the new sibs locally, the sun is beginning to shine, so expect a long hot summer cold water sibbing around.

Will answer you soon about inquired local products prices, maybe you need to move to the southern hemisphere for a European change. Been seing lately ships from abroad visiting us.

Thanks all for their inputs

Happy Boating

Channel Ribs · 22 October 2008, 06:36

Quote:

Originally Posted by Locozodiac

If you would like to place an aux engine next side to main engine on a complete horizontal 40.5 cm height transom, so no need for lateral jack plate. Do you have to raise main engine from water or simple leave on water in a straight locked position and just steer with aux engine, what would be the correct procedure to do so.

If you had a twin engine installation and one of them broke down, would you raise the dead one or leave it in the water?

I am pretty sure you will find the auxiliary will not cope well with another engine in the water.

Locozodiac · 22 October 2008, 17:07

Quote:

Originally Posted by malthouse

If you had a twin engine installation and one of them broke down, would you raise the dead one or leave it in the water?

I am pretty sure you will find the auxiliary will not cope well with another engine in the water.

With same twins that would be the way to go and definitely will not cope at all with remaining engine. Think this case is bit different as a 5 HP won't plane a 2 pal 380 sib, so very little throttle will need to be applied to have the sib at a horizontal position for least water drag. 9D280 stated: I have steered 5+m ribs running with the aux locked ahead and using the main engine as a rudder. Just was inquiring the opposite.

In a near future under trial & error will experiment, have to wait for the new sibs to arrive, in 30 seconds will know what's best for the aux in that particular sib/engine combo.

Happy Boating

Poly · 22 October 2008, 17:49

Quote:

Originally Posted by Locozodiac

...9D280 stated: I have steered 5+m ribs running with the aux locked ahead and using the main engine as a rudder...

yes loco - but as he said this is with a console set up - which allows you to sit on the jockey and steer with wheel, giving you better comfort and visibility than sitting at the back especially in a bigger rib.