Long Shaft or Mid Shaft ?

mdt · 29 January 2006, 18:37

Have got a Humber Assault and have been looking at getting a new engine for it. Have been offered a Mariner 40hp ex RNLI (2stroke) but these are a mid length shaft and not the recommended (by Humber) long shaft.

Would a mid length shaft make a huge difference over a long shaft?

And what weight are these engines?

Tim M · 29 January 2006, 20:40

67kg if i recall.....

jwalker · 29 January 2006, 23:08

Quote:

Originally Posted by mdt

Have got a Humber Assault and have been looking at getting a new engine for it. Have been offered a Mariner 40hp ex RNLI (2stroke) but these are a mid length shaft and not the recommended (by Humber) long shaft.

mdt, I think you may be confused. The RNLI engine is likely the correct length. Short shaft, long shaft (not mid) and then there is extra long. If this is FYM, ask them again about the length.

yeehaa · 29 January 2006, 23:47

I think the rnli 40 mariner will be an excellent engine for the humber because:

- long shaft.
- has special features such as gel coated electrics inversion proofed.
- tend to be very well maintained with low hours.
- can be upgraded to take remotes and elec start.
- plenty of power for cruising and towing toys/ski-ing

Poly · 30 January 2006, 18:47

Quote:

Originally Posted by Tim M

67kg if i recall.....

the current 40 HP 2-stroke models are 75-93 kg depending on the exact spec (looks loke PTT is what add the extra).

how much extra speed do you think this will give you?

Neil

ADS · 30 January 2006, 18:56

According to this BHM advert the shaft length on ex rnli engines is between mid and long.

http://www.boatsandoutboards.co.uk/view/BHM330/

yeehaa · 30 January 2006, 18:57

it should give you around 25+ knots even with no ptt.
at least it is gas assit so nice and light to lift at the slip

mdt · 30 January 2006, 19:23

Quote:

Originally Posted by yeehaa

it should give you around 25+ knots even with no ptt.
at least it is gas assit so nice and light to lift at the slip

Well have currently got a 25hp 4 stroke with elec start and PTT and it weighs in at about 90kg and after juts having the prop refurbished, in very flat water (yes Neil some times it is nice and calm hehehe) 21 knots… not really enough to worry the seagulls.

Yes the gas assist will make it easy but not as easy as the PTT and one would be down to pull starting it too.

Poly · 30 January 2006, 19:32

Matt,

Is not having PTT enough of a disadvantage to take away the benefit of going that extra 5 knots? I think I would have stayed a lot drier when we went out if I could have adjusted the trim to keep the bow higher (certainly seemed a lot better on the way back from Inchkeith with the boat 1/2 full of water!!!).

Cheers,

NEIL

ADS · 30 January 2006, 19:46

Have a friend with a 2001 one of these that has gas assist, its quite easy to lift and has an infinte number of trim settings, it is pull start but its very easy, even my gran could start it. However ptt is an advantage for that extra bit of speed, electric start, something else to go wrong, although I do have it!

Alot less to go wrong so is very reliable, its also for sale pm me if any ones looking for one.

regards
Alex

mdt · 30 January 2006, 19:51

Thanks guys but………. Will it fit on my RIB which apparently needs a “long shaft"???

ADS · 30 January 2006, 19:58

Quote:

Originally Posted by mdt

Thanks guys but………. Will it fit on my RIB which apparently needs a “long shaft"???

measure your trasom and then get the vendor to measure the outboard down to the cavitation plate. Or phone Bill Higham marine from the ad I posted as they specialise in them.

yeehaa · 30 January 2006, 21:35

Quote:

Originally Posted by mdt

Thanks guys but………. Will it fit on my RIB which apparently needs a “long shaft"???

the mariner should fit the humber assault no problem. if it doesnt there are ways round it being a short

yeehaa · 08 February 2006, 00:14

just wondering how you got on with this engine.