Tohatsu Auxilary for searider 5.4

matt h · 08 February 2007, 20:10

i know this is short notice but, any ideas on the right aux for this hull,?? ive found a superb price for a 3.5 Tohatsu 2 stroke,(13kgs) is this big enough to do the job?? and also will it fit on the back in an emergency,??
or do i need a 5 hp,??
im planning a long run, from the severn Bridge in the summer all the way around the coast ending up in Teignmouth on the south coast,i do need some sort of back up,, Any ideas?? Thanks chaps

PeterR · 08 February 2007, 21:08

Hi Matt,I,m sure you know really, rule of thumb 1hp per metre it wont change however good the price is for a 3.5hp is.Sorry

Downhilldai · 08 February 2007, 23:56

Matt - I wouldn't dismiss this until you've heard from someone who's actually tried one of these on a SR5.4.

Nos4r2 · 09 February 2007, 00:01

Rule of thumb doesn't really work on the smaller Seariders unfortunately as the transoms are too narrow and the positioning of the transom eyes can get in the way too. It's literally a case of use what you can and hope it's enough unless you mount a specific bracket for one.

Take your boat with you and try them on it. It's the ONLY way you'll find out if it'll fit.
I struggle to get a 2hp single screw-clamp type Evinrude on the back of my 4m-there's maybe 2mm between it and the main engine at full lock.

Biggles · 09 February 2007, 00:24

Quote:

Originally Posted by Nos4r2

I struggle to get a 2hp single screw-clamp type Evinrude on the back of my 4m.

Is that the hybrid outboard. Petrol and electric shock powered

Nos4r2 · 09 February 2007, 00:40

Quote:

Originally Posted by Biggles

Is that the hybrid outboard. Petrol and electric shock powered

Yeah

Did you like my strange dance moves?

I've sorted that out now-it had a hairline crack in the plug cap.

Biggles · 09 February 2007, 00:52

Quote:

Originally Posted by Nos4r2

I've sorted that out now-it had a hairline crack in the plug cap.

You could do a lot with that !!!

Pete7 · 09 February 2007, 09:22

Matt, some years ago we trialed a couple of outboards before deciding which to buy. The first was an older Yamaha 4 hp short shaft with a solid prop. It only just managed to push an Osprey 5.25 at a couple of knots and each time a wave passed under the boat when motoring into the waves the prop would ventilate as it was lifted to close to the surface (it was mounted directly on the transom). The propellor was quite a bit smaller than the later engine and in addition the short shaft didn't reach down enough to be in clear water, instead the prop was sitting behind the transom.

The second engine was a later Mercury 5hp long shaft with through hub exhaust. This easily reached down under the transom and with the bigger prop was able to give a consistent 4-5 knots. Although it had a built in fuel tank of about 1gallon, it could also be connected to a red tank and came fitted with a tap to switch between the two, a major advantage if you have to motor any distance. Since it drove the rib quite well I opted for this one. However a long shaft aux is can be difficult to store and as Matt said the Searider hulls are quite narrow. Mounted directly on the transom chances are a long shaft aux will drag in the water even when tilted.

Some suggestions, consider using an aux bracket, it might give you more room on the transom, however despite the manufacturers claims they do look a little flimsy to permanently mount an aux on. Seen some ribs with a modified seat back rest supporting the aux mounted vertically, looks neat, takes up little room and is much more secure.

Given the journey you are planning, I would strongly consider a larger outboard, but could you borrow one first to try out first?

Pete

Nos4r2 · 09 February 2007, 13:14

I've got a short shaft 3hp Seagull here if you want to try it Matt-Seagulls may be out of the ark but are better at pushing you along at displacement speeds than most other small aux's IMO.

It's too wide at the petrol tank to fit on my 4m alongside the engine -there's only about 30mm in it-but it might fit yours.

bedajim · 09 February 2007, 13:18

Hi

I made this bracket for my 4 m sr and had a 5hp yam long shaft on it. I used to tie it to the A frame top and bottom too

Never had to use it but used the oars the only time I didn't take it

James

Nos4r2 · 09 February 2007, 13:35

Quote:

Originally Posted by bedajim

Hi

I made this bracket for my 4 m sr and had a 5hp yam long shaft on it. I used to tie it to the A frame top and bottom too

Never had to use it but used the oars the only time I didn't take it

James

Sods law

IT looks like your A-frame is a lot stronger than mine-and possibly Matt H's too. The brace from it is a good idea.

bedajim · 09 February 2007, 13:43

Quote:

Originally Posted by Nos4r2

Sods law

IT looks like your A-frame is a lot stronger than mine-and possibly Matt H's too. The brace from it is a good idea.

Yep it was 4 mm stainless tube we had a some at work/ the braces really made it steady

matt h · 09 February 2007, 14:41

that looks superb, really good, ive measured mine and there is no way it will go on, im going to retain the original searider a frame, which leaves nil space!!
even a aux bracket will not fit,!! bugger!! time for a re think!!

Nos4r2 · 09 February 2007, 15:11

It is a bit tight looking at that! Is there not room to fabricate an adaptor plate to fit a home-made aux bracket to the A-frame mount?

matt h · 09 February 2007, 15:23

this weekend im going to look at that idea!! reckon thats the only option, we have got so much snow here, i cant get to the boat!! anyway, just bought my self a Gecko helmet, ive really needed one!! so looking forward to that arriving!!

Pete7 · 09 February 2007, 16:11

Quote:

Originally Posted by Nos4r2

I've got a short shaft 3hp Seagull here if you want to try it Matt-Seagulls may be out of the ark but are better at pushing you along at displacement speeds than most other small aux's IMO.

Agreed have a 5hp Silver Century long shaft which pushes 2 tonnes of Old Spice at 3 knots. Also have this one kicking around the garage looking for a good home, short shaft 5 hp silver century.

Pete

matt h · 09 February 2007, 17:14

that looks a work of art!! superb, keep hold of it and in 50 years or so would be worth loads!!

davis · 10 February 2007, 20:24

I also am having a problem trying to fit my Aux on a Valiant 4.9, there is nowhere for the Aux bracket, does anybody carry their Aux on board and how do they carry it. Wouldnt it be difficult to fit on the transom or bracket while the boat is rolling while stopped at sea, even very dangerous?

Pete7 · 10 February 2007, 20:35

Depends how heavy an outboard you have I suppose. A 10 Hp Mercury is going to weigh 30 kgs, but a 3.5 hp Tohatsu/Merc/Johnson is only 12 kgs and that Seagull above is 19 kgs, easy enough to carry with one hand.