Driving 90 hp outboard at 4 knots?

adon

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Hi, newbie here. Firstly, I am looking at buying my first boat, a Jeanneau Merry Fisher 625 (I might start a separate thread about that). The boat I'm looking at is on the west coast of Scotland and I am on the east. I would really like to bring it back here through the Forth & Clyde Canal but I'm a bit concerned that running the 90 hp outboard at the canal speed limit of about 4 knots for a few days. Anyone know if that would cause problems for the engine?

Any insights gratefully received.

Thanks

Jamie
 
Worst case is that the plugs get a bit oily, but a quick plug clean, or a "blast" at the other end will sort things out.
 
As long as its a modern 4 stroke it will go all day at that speed. My last 4 stroke 40 efi did most of its time at tickover while fishing
 
Welcome to the forum


We had a 625 with a Suzuki df90 outboard. It would tick over at 4 knots almost silently. A beautiful engine. You won't
have any worries at all.

FYI at that speed it will be slipping fuel at a rate if about 2lph
 
2 or 4 stroke? Most likely 4, then idle or any other rpm no problem.

I used to have a Suzuki DF140. Sooo sweet :)

Enjoy this - espiecially the first seconds at idle
 
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2 or 4 stroke? Most likely 4, then idle or any other rpm no problem.

I used to have a Suzuki DF140. Sooo sweet :)

We had a df90 that was 4 stroke. It's actually a detuned 115hp so nice unstressed engine.

But I would advise anyone to have a close read of the handbook and study service notifications and all warning beeps etc that the engine can make, and when it does how to reset so it does not go into a limp mode.
 
Go up to Fort william and use the caledonian canal into loch ness no speed restrictions there, out into the open water at inverness and go as quick as you like. Look out for a long black thing in the water though.
 
we did the fourth & clyde a few years ago when we moved our boat from Hartlepool to largs & it was in "interesting" journey

its not like other canals where you go at your own pace,you will have a team of bw guys operating the locks for you & kind of at their pace we entered in an afternoon & they wouldn't let us move until the next morning as the guys start at the beginning in the morning
we were expected to be through to the stables (halfway point) by the first evening & be at the next lock first thing the following morning to ensure we were through Maryhill before the drugies got out of bed & started harassing people although we never saw any sign of trouble there were stories of bother with yobs
we were encouraged to "get a move on" on some of the longer stretches so the bw guys weren't waiting for us so you will get the chance to open up a bit (although not officially)
we asked if we could do the Falkirk wheel & they allowed us to turn off & go through the wheel,turn around & come back down which was pretty awesome look out for the sail thru fish & chip shop at kirkintilloch (I think)

you need to watch out for weed at bowling end too but early in the year it might be ok but we did it in july & needed to keep an eye on intake strainers

obviously you will be heading the other direction to us but we enjoyed the trip & it makes an easy trip from east to west or vice versa

I guess your approach to the sea lock at bowling would need to be carefully planned as there wasn't a waiting pontoon when we went through & its not a very inviting part of the river to wait in

we've also done the Caledonian but its a hell of a hike further round & exposed once past fraserburgh

good luck with the trip it would be interesting to hear how you get on
ken
 
No Problem at all. I used to use my 5.5m Centre Console on the Thames, though I had an ETEC 90HP. Only issue was after a few weeks plodding she needed a decent blow out so took her to the Solent. Job done! Great boat BTW for the UK, hope you have a lot of fun on her.
 
I used to have a Honda BF90 on a rib. Not that I was ideling around too often but one thing I'll say is that it needs constant steering adjustments to keep it in a straight line at tick-over speed which can get annoying after a while. A Merry Fisher might behave the same way...
 
I used to have a Honda BF90 on a rib. Not that I was ideling around too often but one thing I'll say is that it needs constant steering adjustments to keep it in a straight line at tick-over speed which can get annoying after a while. A Merry Fisher might behave the same way...

Mf 625 had a small keel which does help with directional stability. Tilt engine fully in sometimes helps a bit, but I can't really remember it being an issue.
 
I used to have a Honda BF90 on a rib. Not that I was ideling around too often but one thing I'll say is that it needs constant steering adjustments to keep it in a straight line at tick-over speed which can get annoying after a while. A Merry Fisher might behave the same way...

Nothing to do with the engine. 100% related to hull design and a common property of planing designs.
 
Nothing to do with the engine. 100% related to hull design and a common property of planing designs.

I understand that. My point is a small planing hull hull boat with c.90hp outboard motor might be tiring to drive at 4 knots after a while.
 
Ah, yes. I had a Salpa 20.5 with my Suzuki 140. Planing hull but not too bad at the wander as it seemed to find a rythm around the desired direction.
 
Thanks for all the replies. Excellent! So it seems there's no problem with this and that video of the outboard is great. I'm itching to get one of these now.

Next thing is how to buy this boat, I think I'll start another thread about it...
 
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