Engines

[Andy]

Hi all.

First, is it possible to buy an engine that will work as a tiller, but be able to be used if i decide to add a console at a later stage. So I suppose be able to take a steering cable, electric start and electric tilt ?

As regards matching engine HP size to length of Rib, is there some formula that should be adheard too? For instance, an 100hp OB on a 3.4M rib is stupid as well as probably too heavy at the back, but if you take the ocean runner as an example, they reccommend not using one larger than 20HP on a 340, but it is possible to go up to a 40HP on a 420. If you were to put a 20HP on a 420 would this be detrimental ? If you put a 40HP on a 420, surely the speed increase would be minimal compared to a 20HP, but the weight gain a disadvantage ?

Solar

[chris moody]

I generally try to keep the engine size at or just below what's on the CE plate. If you over engine it's a lot harder to insure it.

So my rib is plated maximum 60hp and I put a 50hp on it (only because I already had the 50hp). If I had been buying the engine specifically for that boat I would have gone for a 60hp. My thinking is on all the various boats I've used I've never ever said This boat is overpowered" but lots of times I've said "This boat needs a bigger engine".

Just because you have the power doesn't mean you have to use it all the time. But often, you find occasions where that power is really useful. Today we were out in a F5 gusting F6 in a following sea and quite often I was at full throttle jumping onto the back of the next wave, with no spare horsepower in reserve at all. A 60hp would have been much better in those sea conditions on my rib.

The only time I would seriously underpower is on a Sib where often portability (weight) is the overriding factor. my new Takacat is rated to 15hp, but I'm putting a 10hp on it as that's much lighter to carry.

[harrison]

Second Chris's advice above, ideal at or just below rated max power. If you seriously overpower for hull length, the additional weight can upset the balance of the boat causing difficult handling in big seas.

Most manufacturers will also advise a min hp while the max will be plated on the transom. For the Ocean Runners;

460 is 60hp max/20hp min
420 is 40hp max/ 15hp min
340 is 25hp max/ 8hp min

Maximum fun and safety will be had with the larger engine. At a guess a 460 with 20hp lightly loaded will get on the plane and probably do just over 20mph flat out. It won't feel very spritely and may struggle to maintain planing speeds at ideal cruising revs of 4000/4500rpm.
The same boat with a 60hp moderately loaded may achieve around 38mph, cruise all day at 25mph/4000rpm and nip on and off the plane with little effort.

Whilst possible it will be a very costly exercise to convert a tiller outboard to remotes, and generally not a viable option using new parts. Also very few outboards over 30hp are available tiller only - Mercury do their 'Big Tiller' option. If you want tiller only initially on an open hull perhaps better to just get a manual start smaller motor say 25/30hp then sell on/upgrade to a larger motor on remotes when you want to fit a console. Bear in mind the Ocean Runners take a long shaft motor and these will be in less demand than short shaft tiller models.

As open boats the 420/460 would probably go quite well with a 30hp tiller motor lightly loaded as the bare boats only weigh around 120/130kg. Fit a consul, seating and a few bodies etc. then will certainly benefit from more horses.

[chris moody]

I think the key thing is to try out:

• A tiller steer boat sitting on the tubes / gunnels

• A wheel steer boat with jockey seating

• A wheel steer boat with bench seating

• A wheel steer boat with individual seats

It will be immediately apparent which you like best from a quick run out in each style (or possibly just sitting in each). You will not work this out unless you go and sit in some boats. A visit to the Southampton Boat Show might be the ideal way to achieve this.

Trying to retro fit consoles and seating, and converting engines isn't going to cost effective.

[PeterM]

I'd echo what's been said. Smaller boats don't tend to cope with weight of the max rated engines well if the max jumps to the next size up.

For example my small rib is rated to 50hp. I put 50hp on it.. but it's the same weight as the 60! I actually wish I'd put the 40hp on it as this is much lighter and I rarely use it when I need all 50hp.

Likewise Chris mentions his sib. He's putting 10hp on it although it's rated to 15. I've heard 15 makes it a handful to manage on the water...

On smaller engines most can switch from tiller to remotes by the purchase of an aftermarket kit.... check out prices as the genuine new ones aren't cheap. Ideally go for what you need from new... but what you need and what you want or can carry or use tend to be differant:(

[chris moody]

Loads of excellent advice on this thread solarsurfer.

[Cliff]

I think the key thing is to try out:

• A tiller steer boat sitting on the tubes / gunnels

• A wheel steer boat with jockey seating

• A wheel steer boat with bench seating

• A wheel steer boat with individual seats

You can also sit on a rear bench seat and tiller steer

As to the engine size bang on the max

[Paul]

All good advice given previously
Why not give us your location as you may well be offered first hand experience of the craft your're researching

[Andy]

All good advice given previously
Why not give us your location as you may well be offered first hand experience of the craft your're researching

Bedford !

All good advice, still unsure about boat length, but I think smaller might be a good start, until I know what's what, and seats seem to be an advantage if I am fishing for long periods, rather than a jockey. Jockey seems fine if you intend to race around all day like a lunatic, but when fishing aint that comfortable or ideal.
I saw some really nice 5.2m ish boats but then I'm back up to heavier stuff and mostly I intend to launch by myself. There are lots of good gear coming onto the market now, end of season, and it seems that the Mercury has a new updated model coming. So if they intend to refurb all the range there could be some bargains. If I do go for a 340 then space is limited with a jockey. At the end of the day, I still dont want to go too far out while I get some exp, and not on rough days, until I understand the logistics and how to treat waves etc.

[chris moody]

I launch a 4.8m boat single handed off a trailer and that's easy. I personally would not be worried at all about launching a 5.2m rib or hard boat single handed.