Yamaha 9.9 4 stroke

[macroft1]

My "new to me" Norman 20ft has a Yamaha 9.9hp 4 stroke outboard. Has anyone had experience with this motor on The Broads? I've been told that it's up to the job but has it any limitations? Just say we had to go against the tide at full ebb down at Yarmouth - not something I plan to do but would it cope? Regards and thanks in advance. Mark.

[JawsOrca]

I'm going to hopefully beat strowager too it. .although I notice Mark is on the thread!

 

Mark.. it will push you at about 5 kts .. A norman (I think) is a displacement hull which means it's hull speed is limited to something like 5 or 6 kts.. You can go faster than this if you got a really big engine on.. but its not worth it.. There are lots of Normans on the broads with these engines so they do work..

 

As for hitting breydon against the tide.. you wouldn't really want to do this (anyway).. if you would with a small displacement boat you would only just beat the tide (you may go backwards)...and it would cost a fortune on fuel.. just go with the flow don't forget having your own boat means you can go after dark so there will be no panic to beat the tide anyway!

[MauriceMynah]

A 9.9 Yammy 4 stroke is more than up to the task. great engine in my (as you will soon find out) vastly less than humble opinion (or "IM(AYWSFO)VLTHO).

 

I never say "IMHO"

 

Actually I will just add that given the weight of the Norman 20, it wont even be that thirsty. You will soon learn the fuel consumption of your engine anyway

[650xs]

just had a customer bring a 22 foot Weston 670 from brundall last week in middle orf ole sept tides all good no worries

 

good ole lumps nice motors

 

 

plenty orf drive there ....

 

 

or do yer want to go water skiing ...????

[Guest]

I'm going to hopefully beat strowager too it. .although I notice Mark is on the thread!

 

Mark.. it will push you at about 5 kts .. A norman (I think) is a displacement hull which means it's hull speed is limited to something like 5 or 6 kts.. You can go faster than this if you got a really big engine on.. but its not worth it.. There are lots of Normans on the broads with these engines so they do work..

 

As for hitting breydon against the tide.. you wouldn't really want to do this (anyway).. if you would with a small displacement boat you would only just beat the tide (you may go backwards)...and it would cost a fortune on fuel.. just go with the flow don't forget having your own boat means you can go after dark so there will be no panic to beat the tide anyway!

 

I believe that most Normans are actually planing hulls, but may be wrong.

 

If so, as with all small planing cruisers, engine power requirements fall into two very different HP ranges.

 

As MM and JA have said, 10hp is perfectly adequate for maximum displacement speeds for that waterline length, which would be about 7 to 8 mph.

 

If the hull can plane, then a 20ft  cruiser would weigh about 1 ton, and would need at least 60hp to plane, more likely 70 or 80 hp, then it could get "over the hump" and skim along at about 20 to 25 mph.

 

Many people fit something in the middle, like a 30hp, which is largely wasted, since that combination can't get much faster than about 10 to 12 mph, stuck "on the hump", with a massive wash and lousy fuel consumption.

[macroft1]

Thanks for great comments. Being new to boating I can't tell the difference between planing and displacement hulls. Is there a way that can identify which it is? Thanks. Mark.

[JawsOrca]

Thanks for great comments. Being new to boating I can't tell the difference between planing and displacement hulls. Is there a way that can identify which it is? Thanks. Mark.

 

Mark.. if the hull is shaped like a traditional boat (imagine "HMS victory") then's its a displacement hull.. if it looks like a little speedboat then it's planning or semi planning..

 

Heres the wiki link:

http://en.wikipedia.org/wiki/Hull_(watercraft)

 

Strowager is right a Norman appears to be a planning hull.. (There's only soo much google imaging I can get away at my desk in work ) 

[macroft1]

Mark.. if the hull is shaped like a traditional boat (imagine "HMS victory") then's its a displacement hull.. if it looks like a little speedboat then it's planning or semi planning..

 

Heres the wiki link:

http://en.wikipedia.org/wiki/Hull_(watercraft)

 

Strowager is right a Norman appears to be a planning hull.. (There's only soo much google imaging I can get away at my desk in work ) 

I think you're right! To be honest I only intend to use it on The Broads so as long as it will push along at 4-6 mph without struggling then I'll be more than happy.

[Guest]

Thanks for great comments. Being new to boating I can't tell the difference between planing and displacement hulls. Is there a way that can identify which it is? Thanks. Mark.

 

It can be difficult to tell without seeing the underwater part of the hull.

 

The biggest clue with motor boats is how far the transom extends below the waterline. On planing boats it's usually quite deep and boxy, to provide the buoyancy to support the weight of the engine(s) when planing along with it's weight at the stern.

 

That causes a very blunt and abrupt end to the flow of the water past the boat at slower displacement speeds, giving much more drag as the water rushes up to fill the void.

 

Displacement craft are much more streamlined at the stern, to cut along through the water with minimal drag. Even though most displacement motor cruisers still have large flat transoms, very little of it extends below the water line.

 

These two views show both types of hull from below the surface.

 

Although the displacement one is of a sailing yacht, the same principle applies, there's little or no flat transom below the waterline.

[macroft1]

It can be difficult to tell without seeing the underwater part of the hull.

 

The biggest clue with motor boats is how far the transom extends below the waterline. On planing boats it's usually quite deep and boxy, to provide the buoyancy to support the weight of the engine(s) when planing along with it's weight at the stern.

 

That causes a very blunt and abrupt end to the flow of the water past the boat at slower displacement speeds, giving much more drag as the water rushes up to fill the void.

 

Displacement craft are much more streamlined at the stern, to cut along through the water with minimal drag. Even though most displacement motor cruisers still have large flat transoms, very little of it extends below the water line.

 

These two views show both types of hull from below the surface.

 

Although the displacement one is of a sailing yacht, the same principle applies, there's little or no flat transom below the waterline.

Looking at those I'm pretty sure it's a planing hull. How do you upload photos on here? I could post a pic of the hull if I could find out how.

[Guest]

Looking at those I'm pretty sure it's a planing hull. How do you upload photos on here? I could post a pic of the hull if I could find out how.

 

When you click to reply, the first "reply" box has a button under the bottom right hand corner "more reply options".

 

When you click that, a bigger edit box opens with "attach files" underneath it.

 

click the "browse" button to select the image file on your computer, then click "attach this file".

[VetChugger]

The only Normans with genuinely planing hulls are the 18, 20 and wide beam 22. The rest are displacement and were specifically built/designed for use on the canals.

[VetChugger]

There are two much bigger models that were built just before Norman packed up. The Norman 266 and Norman 29 with 9' 6~ and 10' beams respectively. You might be surprised to learn that they also produced a rag on a stick version!

 

This page may be of interest!

 

http://www.normanboats.co.uk/norman_range.htm

[VetChugger]

Or even this? This page was done for us by Graham who was the son of the Norman founder Ernie.

 

http://www.normanboats.co.uk/brief_history_of_norman_cruisers.htm

[macroft1]

When you click to reply, the first "reply" box has a button under the bottom right hand corner "more reply options".

 

When you click that, a bigger edit box opens with "attach files" underneath it.

 

click the "browse" button to select the image file on your computer, then click "attach this file".

Thanks - here goes.

[VetChugger]

Have you any more pictures of the topsides Macroft? I have a wee suspicion that yours may actually be a Norman 18.5!

[macroft1]

Have you any more pictures of the topsides Macroft? I have a wee suspicion that yours may actually be a Norman 18.5!

I haven't no but I've seen plenty of pictures on the net of 20s and they do look identical to mine. What makes you thinks it's 18.5? Can you tell the hull type from those pics? Regards, Mark.

[Guest]

If Vetchugger is uncertain of which Norman it is, then it must be a tricky one to be sure of.

 

I'd say it's definitely a planing hull though, the Transom has a deep V and large flat underwater area.

 

Also, the narrow hard edged ridges in the moulding under the bow chines are "spray chines", which deflect spray when it's right up on the plane. They're never found in displacement hulls.

 

(By the way, the antifoul has been painted to way above the waterline, by maybe 6" or so.)

[macroft1]

If Vetchugger is uncertain of which Norman it is, then it must be a tricky one to be sure of.

 

I'd say it's definitely a planing hull though, the Transom has a deep V and large flat underwater area.

 

Also, the narrow hard edged ridges in the moulding under the bow chines are "spray chines", which deflect spray when it's right up on the plane. They're never found in displacement hulls.

 

(By the way, the antifoul has been painted to way above the waterline, by maybe 6" or so.)

Many thanks for all the info.

 

Excuse my ignorance but what exactly is antifoul? Sounds like something to deter chickens!

 

As regards the length I'll get my tape out tonight but it's difficult to measure. The previous owner advertised it as a 20 but these are supposed to be 4 berth - two up front & two under the canopy. Mine would accomodate two people in the back as long as they were no more than about 4ft tall!! This makes me wonder if Vetchugger may be right about it being 18.5'. Makes no difference to us though as it's just for the wife and me and two small dogs but I would imagine it could make a difference to insurance costs and tolls?? 

 

Regards.

Mark.

[MauriceMynah]

May only be a small saving but Mooring fees too!

That really does look like a tidy boat with a smart looking outboard. Just the job!

 

Antifoul is the blue paint on the bottom of the hull and someway up the sides. It stops things growing there!

[Guest]

......Excuse my ignorance but what exactly is antifoul? Sounds like something to deter chickens!.....

 

No, nothing to do with poultry Mark, though a lot of people do spell it as "antifowl"

 

It's the paint used up to the waterline on hulls that resists algae and crustacean growth.

 

It comes in two types, "hard" and "eroding".

 

Eroding wears away gradually, giving no grip to the growth, and Hard is a Teflon like surface that is a smooth enough finish to resist the growth without wearing off.

[macroft1]

No, nothing to do with poultry Mark, though a lot of people do spell it as "antifowl"

 

It's the paint used up to the waterline on hulls that resists algae and crustacean growth.

 

It comes in two types, "hard" and "eroding".

 

Eroding wears away gradually, giving no grip to the growth, and Hard is a Teflon like surface that is a smooth enough finish to resist the growth without wearing off.

It was painted by the previous owner so not sure if it is antfoul. The tin of paint did come with the boat and is marine spec so I can have a look what it says on the tin later today. 

 

Does it need to be antifoul? It will only be on the water while we're using it and sat on my garden the rest of the time.

[ranworthbreeze]

Hello Mark,

My business partner uses a product called Simply Green when he removes his boat from the water on his travels.

It gets the algae and any marks off of his boat.

On our boat we use Muck Off for cleaning the hull but because it is always in the water other than coming out for its winter service it is antifoulled.

Regards

Alan

[macroft1]

Hello Mark,

My business partner uses a product called Simply Green when he removes his boat from the water on his travels.

It gets the algae and any marks off of his boat.

On our boat we use Muck Off for cleaning the hull but because it is always in the water other than coming out for its winter service it is antifoulled.

Regards

Alan

Thanks Alan.

 

Muck Off is good - I've used it on my off road motorcyles.

 

.

Mark.

[Guest]

It was painted by the previous owner so not sure if it is antfoul. The tin of paint did come with the boat and is marine spec so I can have a look what it says on the tin later today. 

 

Does it need to be antifoul? It will only be on the water while we're using it and sat on my garden the rest of the time.

 

No, it doesn't have to be painted with antfoul, there's no protective function, it merely reduces the amount of algae or barnacles when left afloat for more than a few weeks.

 

A jet wash will remove most contamination without the need for any chemicals.