Same old question which sib - Page 3

Scomich · 04 August 2019, 20:52

Hi all,
Ok maiden voyages undertaken. Lol.
First launch disaster from Portobello beach. Yup I done it forgot to take the wheels off. Lol.
Put yr hands up if.youve tried that 1. Lol
. Only.laumced they're cause it was low tide. Anyway that sort of killed that 1

Second launch from Granton harbour very successful took a jaunt around cramond island and as far up the almond as we could get. Then on way back went into Newhaven harbour then back to base.

Some interesting chop around cramond island , but my son enjoyed me sitting in the front being soaked.

Thoroughly enjoyed it even with torrential rain.

Think I have a bit to learn I would say of you call it this that the outboard pitch angle is way off. Obviously with that engine we can't plain .maybe with 1 but not 2.
So engine it is then albeit the wee Yamaha 6hp done the job . I was impressed and even more so with the handling of the boat. Amazed in fact.
Dunno what the distance travelled was but we used just under half tank of fuel. So again can't complain.
I'm hooked. Lol.

1 thing I would ask is the water outlet what is enough water coming from that ?
I checked continually and somemtimes it was down to a slow stream other times a squirt, so any advice on that 1 would be appreciated.

We did encounter a plastic bag wrapped around prop during the cramond jaunt but quickly and easily fixed , can't remember who said it on this forum but they're advice was always carry a multi tool thanks for that 1.

Sorry for the long post but I'm as happy as a pig n shit. Excuse the phrase. Lol

Bigplumbs · 04 August 2019, 21:19

Well done sounds like you had a very good fun day

Fenlander · 04 August 2019, 21:30

We've had a great day out in F5 today, great fun. Glad you had the same.

Re the pee indicator... they are all different and ideally it would be good to hear from someone with your outboard model as to how they should be. But by and large a strong pencil like jet should be seen.

Scomich · 04 August 2019, 21:50

Thank you both for yr replies. Yeah was great fun. I will most likely strip the engine down take a look at the impeller and just change it anyway. Also oil and spark plug albeit this wee motor starts no problem. But I have a very lax job so that'll keep me occupied. Would.love to see this boat on the plane , think that would be a blast. Bit I'm happy with today's venture.
If.it makes any difference I did constantly feel the water coming from the pee hole . My thoughts on that 1 were if the engine ain't cooling properly the water that was coming out would be very hot. It only.got warm at best , never hot.
Again that's only my thoughts. And I could be way off.
I'm handy with a spanner anyway so could be a wee project for me.

Scomich · 04 August 2019, 22:05

I'm reading some of you guys do some amazing trips. Camping and adventures . Now this does interest me a lot. I have all the gear for camping dry bags tent cooking facility's. But again guessing I'm gonna need to travel a bit faster for this sort of excursion. And possibly.another fuel tank. Most likely I'm running before walking. But I have a lot more space now than I did on the kayak. So much so. Feels huge . Lol.

Bigplumbs · 05 August 2019, 06:02

You need to see if you can find yourself a nice 15 or 20 hp engine. So tha the 6 hp can be used for river trips and the larger engine for the sea and longer trips.

Bigplumbs · 05 August 2019, 06:24

Nice 15 hp bargain here

https://www.gumtree.com/p/boats-kaya...ine/1348193880

beamishken · 05 August 2019, 07:22

The 6hp yam is exactly the same engine as the 8hp maybe worth looking at how to unleash the extra 2hp doesnt sound much but its a 1/3rd more than you had
The 8 hp yam is a sweet little engine and very capable for its light weight. Anything bigger will be a big increase in weight, even the next size up 2 stroke 9.9/15hp is significantly heavier and a 4 stroke will make your eyes water trying to lift it

Scomich · 05 August 2019, 07:50

Cheers I'll have to double check unless any of you know but I think max hp for that boat is only 10 hp. Would that be gospel or can I over power it slightly without affecting anything?

I'd be interested in unleashing the little extra as well out of the Yamaha 6.
But I wouldn't part with it me and it have a good relationship already. Lol.

Fenlander · 05 August 2019, 09:50

I agree those 6/8hp Yamahas were really sweet motors. Re upgrading the 6hp to 8hp. You have to be really wary taking advice on this as many folks only have partial ideas on such upgrades. I did investigate this very upgrade about 5yrs ago and had to speak to several folks before I got to the 100% solution. You need to check out the online parts diagram for both models to see any differences and I think in this case it was a new carb or a re-jet plus remove intake restrictor plus (and this is the bit many folks were unaware of) change the exhaust stub to the 8hp version or drill out the existing one. If you are handy with the spanners and such stuff have a look at the parts info and I'm sure you'll sort it out.

Having said that it might be easier to sell this motor and buy a 10hp but for your SIB but there's only one I'd advise due to weight and that's the well regarded Tohatsu 9.8hp 2-stroke (note 9.8hp not 9.9hp, they are totally different beasts).

You are correct your Zodiac is rated for 10hp... with good reason as they are a light build with lightweight transom and do not take well to being overpowered from the construction and handling point of view. They used to be called the 340 until they changed little more than the cone design making them shorter hence 325. I've owned two 340s and used with 4, 9.8, 10 & 15hp motors (when called the 340 they were rated to 15hp but then Zodiac downrated them to 10hp) so know them well.

A bit upthread BP mentions a 15hp Mariner on Gumtree. Good call as far as it goes to think of possibilities but that particular 4-stroke model is a gut busting 54kg and just not suited to your SIB.

Which brings us onto the long distance camping trips up in Scotland... I would get some experience with the outfit as it is and use that as a basis for a whole outfit upgrade because as it is you might be hard pressed to keep up in some of the more difficult conditions seen in the group outings. Something around 3.8m with 15-20hp would be ideal.

I guess you have been watching some of Gurnard's videos? Of course on his solo jaunts he often prefers to use a 2.75m with 6hp but bear in mind then it is all at his own pace with no group deadlines plus he has a lifetime of experience at sea in Scottish waters and is also an excellent tide/current/weather planner.

Scomich · 05 August 2019, 10:06

Thanks again Fenlander for all your advice,
I think i will just enjoy what i have at the moment but possibly with a motor upgrade and upgrade the boat as i grow then.
In hindsight im glad now that i didnt go all out and buy everything new, as most likely with inexperience most likely wouldnt get the best out of it.
and im sure i have a few lessons to learn.

I have a lot of questions to be asked but i dont want to be a complete nuisance, lol.

1 of my friends has a 15 hp 2 stroke no idea what make but i was gonna give that a try, but given your advice i think i will now give that a miss.

even with the wee Yamaha 6 it done well yesterday in my opinion, certainly beats the kayak. but in admission my arms are sore today the amount of times i lifted the engine. good workout though.

Fenlander · 05 August 2019, 10:22

>>> my arms are sore today the amount of times i lifted the engine.

Somewhat similar here. Yesterday (a typical boating day out for us) was a near 100mile trip to the sea... complete setup from packed in the boot... transom wheel trundle a few hundred yards to the slipway... outing in fairly rough but fun sea... then do the whole pack away and return home in reverse.

Now part way into unpacking and washing everything in the garden. Don't begrudge it though.... to be out there on the water mixing it with yachts and large powerboats such as the superb classic Swordsman 37 below makes it all worthwhile.

If you can I'd have a brief go with your mates 15hp 2-stroke. It will say on the OB data plate/sticker but it should only weigh about 36kg which is less than many 10hp 4-strokes your boat is rated for.

It will give you a feel for a brisk on the plane performance.

Scomich · 05 August 2019, 21:18

Well another wee successful jaunt out to inchkeith. Fortunately I've found a guy that stays couple of hundred metres away from my house . And his forte is boats. He has outboards and big boat engines all over his workshop. So that's a wee bonus. Told me to take my motor down and he will give it a wee look over.
On our pleasant little jaunt this evening I noticed when my son gave full throttle albeit he didn't do that much. I can only describe it like we were losing traction. Of that makes sense. Engine would rev higher bit less forward motion. Then it would grip again. Sorry if that sounds daft. But I wasn't to happy about it. As I say only at is it wot you call it?
Could.explain it as a clutch slipping sort of thing . I'm sure they're must be a correct name for it.

Any ideas or explanation would be greatly appreciated

Bigplumbs · 06 August 2019, 06:27

Quote:

Originally Posted by Scomich

Well another wee successful jaunt out to inchkeith. Fortunately I've found a guy that stays couple of hundred metres away from my house . And his forte is boats. He has outboards and big boat engines all over his workshop. So that's a wee bonus. Told me to take my motor down and he will give it a wee look over.
On our pleasant little jaunt this evening I noticed when my son gave full throttle albeit he didn't do that much. I can only describe it like we were losing traction. Of that makes sense. Engine would rev higher bit less forward motion. Then it would grip again. Sorry if that sounds daft. But I wasn't to happy about it. As I say only at is it wot you call it?
Could.explain it as a clutch slipping sort of thing . I'm sure they're must be a correct name for it.

Any ideas or explanation would be greatly appreciated

The most likely explanation is the prop is cavitating. This can usually be cured by trimming the engine leg in more towards the boat. This is done with a pin that goes though the engine mount/ Put it into a hole nearer to the transom and see if this cares the issue.

It could also be that the prop is for some reason slipping on the hub but that is unlikely. More likely just needs trimming in.

I assume it is mounted all the way down on the transom

Scomich · 06 August 2019, 06:39

Hi pal,

Yeah the engine is trimmed all the way in. At the moment. Basically 90 degrees . I could tilt out. But no adjustment to bring it in closer to transom. Sounded like a hissing gurgling bubbling noise then would lose traction if that's what you call it . Then engine would high rev. Then bite again. We just slowed down again and issue was gone, as I say that was at wot. I didn't like the sound of the engine revving so high so just avoided it with lower revs .

Fenlander · 06 August 2019, 09:25

Just to be sure I'm assuming you have the motor below (decals may be a little different but no matter).

So yep as BP says it's either water slip or mechanical slip. I'd agree with him it's less likely to be the prop slipping on the hub with such a low power motor.

But to cover that...

The prop in the factory is assembled from three parts.... an inner sleeve which is splined to engage with the gearbox shaft splines... a rubber tubular bush... and the prop itself. The parts are pressed together very tightly and this gives a little shock absorption within the prop assy so if you hit something hard it protects the gearbox somewhat.

It is possible for the bush to become weak and allow the engine to spin without turning the prop correctly when under load.,,, but usually with higher power motors.

Two ways to check... You can put a nick or file mark on the nut or inner sleeve and a matching one on the prop then take it for a run. If it is slipping the marks will go out of alignment. Or you could take the prop off the outboard... find a long bolt or bit of studding and bolt tight through the inner splined sleeve. Then mount the bolt in a vice and try and turn the prop... it should just feel springy for a few degrees roatation but not actually move.

If the prop hub isn't the problem...

Then it's the prop losing its grip on the water as referred by BP as cavitation. That effect is actually ventilation but it matters not as 50% of folks use the term cavitation and we know what they mean.

The basic things to get right are trim angle which BP has mentioned and that the shaft length is correct for the boat. Do you have a photo of the outboard on the boat so we can see the relationship of the prop/lower leg to the bottom of the transom? It should align broadly as shown in the second image below of a 9.9hp on my SIB. In truth I would expect it to be near enough right as I've not had to fiddle about much with the transom heights on your SIB model.

Re trim yes on some SIB models bringing the trim closer in to the transom can help but that's not my experience with your SIB type... in all cases I ran it with a variety of outboards in the mid trim posn… so unless you have already I would try that mid setting and go from there.

The last thing re ventilation with your SIB model is related to a common issue with that type of air floor. It differs between makes, models, lengths, outboard hp/brand, load carried etc but by and large that floor design is prone to prop ventilation. The more power you put on and the more speed you ask for the more likely it is to happen. That's why I advised not getting a much bigger outboard for this particular SIB.

Do you have any GPS speeds recorded... do you think you were getting on the plane and was it at the just on the plane speed the slip kept happening?

Also what's the pitch of your prop... should be stamped on it... and is it in good condition... photo?

Scomich · 06 August 2019, 09:48

Thanks again Boat is all folded up but if this rain breaks I will set it all up and post picture.
.
The pic you have sent of the outboard on its own

Ok looking at your picture of the outboard my pin is in the far right hole. Guessing I'm way out.

The prop does have a small nic in it on 1 blade, the numbers on the prop are 8 half x 8 -N

Fenlander · 06 August 2019, 09:59

OK so that's the correct prop type (N) and a broadly suitable sounding pitch at 8"... 8.5" is the diameter. Pic of the nic would be good as it could be contributing to the problem.

Yep personally I'd not be starting fully trimmed to the transom... try the midpoint next outing and work from there.

Edit: Something I forgot to query... I think in earlier posts we established you did have or were getting a pump with gauge? Are you sure the whole SIB but air floor in particular is up to pressure... that is really important to stop prop ventilation.

Scomich · 06 August 2019, 10:07

Thanks again Fenlander,
Here a couple of pictures of the nic in prop, this was present when i bought the outfit

Fenlander · 06 August 2019, 10:11

That's not good I'm afraid... refurb £47 plus post plus your post to them and about 10 days turnaround...

https://www.steeldevelopments.net/pr...r-service.html

Or...

OE replacement £78...

https://www.ebay.co.uk/itm/Yamaha-Ge...EAAOSwVYtb3Ang

Budget replacement £45 (note a 7.5" pitch, they do that or an 8.5" but not an 8")…

https://www.ebay.co.uk/itm/Yamaha-Ou...gAAOSwSBhbtgKP