1976 Boston Whaler Re-power Question
 

A fishing buddy of mine is re-powering his early 1976 Boston Whaler
Sport 15 with a new 60hp 4 stoke Mercury. He is replacing a 2 stroke
Mariner that is an 80's model.

He has no gauges and the layout of the console is like a skiff - the
steering wheel is horizontal. He's not concerned about a speedometer,
and shouldn't be, but I think he should have a tach. The 4 stroke will
be heavier and act differently than the 2 stroke. The props are
interchangeable in size and hub configuration so he plans on putting his
SS prop on the new boat. I'm trying to convince him to find, or make, a
spot for a tach so he can make sure the boat is propped properly (say
that 5 times fast!). He's not convinced. The boat is rated for a 75 so
the 60 will still weigh about the same as a 75 2 stroke so the transom
weight will be fine.

Has anyone attempted a similar replacement? Should he need a different
prop? Can you attach a tachometer temporarily for testing purposes?

Thanks in advance,
Larry

1976 Boston Whaler Re-power Question
 

On Mar 3, 7:58*pm, Larry wrote:
A fishing buddy of mine is re-powering his early 1976 Boston Whaler
Sport 15 with a new 60hp 4 stoke Mercury. *He is replacing a 2 stroke
Mariner that is an 80's model.

He has no gauges and the layout of the console is like a skiff - the
steering wheel is horizontal. *He's not concerned about a speedometer,
and shouldn't be, but I think he should have a tach. *The 4 stroke will
be heavier and act differently than the 2 stroke. *The props are
interchangeable in size and hub configuration so he plans on putting his
SS prop on the new boat. *I'm trying to convince him to find, or make, a
spot for a tach so he can make sure the boat is propped properly (say
that 5 times fast!). *He's not convinced. *The boat is rated for a 75 so
the 60 will still weigh about the same as a 75 2 stroke so the transom
weight will be fine.

Has anyone attempted a similar replacement? *Should he need a different
prop? *Can you attach a tachometer temporarily for testing purposes?

Thanks in advance,
Larry

This might provide some useful information regarding prop size. The
tested boat was a Boston Whaler 150 Montauk, which is probably pretty
close to the boat he's got. I had a 15' Whaler center console I bought
new in 1985. It came with a 70hp, Johnson 2-stroke. Screaming little
boat. He should get good performance with the 60hp, unless the boat is
water-logged.

http://tinyurl.com/yd8r5zl

The propellor specs are in the lower right of the page.

1976 Boston Whaler Re-power Question
 

"Larry" wrote in message
...
A fishing buddy of mine is re-powering his early 1976 Boston Whaler Sport
15 with a new 60hp 4 stoke Mercury. He is replacing a 2 stroke Mariner
that is an 80's model.

He has no gauges and the layout of the console is like a skiff - the
steering wheel is horizontal. He's not concerned about a speedometer, and
shouldn't be, but I think he should have a tach. The 4 stroke will be
heavier and act differently than the 2 stroke. The props are
interchangeable in size and hub configuration so he plans on putting his
SS prop on the new boat. I'm trying to convince him to find, or make, a
spot for a tach so he can make sure the boat is propped properly (say that
5 times fast!). He's not convinced. The boat is rated for a 75 so the 60
will still weigh about the same as a 75 2 stroke so the transom weight
will be fine.

Has anyone attempted a similar replacement? Should he need a different
prop? Can you attach a tachometer temporarily for testing purposes?

Thanks in advance,
Larry

Sure, you can hook up a tach temporarily, but he may as well do it right.
There is no way he is going to get the prop pitched properly G w/out a
tach. And, he needs one he can see at WOT... not clamped to the transom
"temporarily." It's not a hard gauge to install at all.

---Mike

1976 Boston Whaler Re-power Question
 

John H wrote:
On Mar 3, 7:58 pm, wrote:

A fishing buddy of mine is re-powering his early 1976 Boston Whaler
Sport 15 with a new 60hp 4 stoke Mercury. He is replacing a 2 stroke
Mariner that is an 80's model.

He has no gauges and the layout of the console is like a skiff - the
steering wheel is horizontal. He's not concerned about a speedometer,
and shouldn't be, but I think he should have a tach. The 4 stroke will
be heavier and act differently than the 2 stroke. The props are
interchangeable in size and hub configuration so he plans on putting his
SS prop on the new boat. I'm trying to convince him to find, or make, a
spot for a tach so he can make sure the boat is propped properly (say
that 5 times fast!). He's not convinced. The boat is rated for a 75 so
the 60 will still weigh about the same as a 75 2 stroke so the transom
weight will be fine.

Has anyone attempted a similar replacement? Should he need a different
prop? Can you attach a tachometer temporarily for testing purposes?

Thanks in advance,
Larry

This might provide some useful information regarding prop size. The
tested boat was a Boston Whaler 150 Montauk, which is probably pretty
close to the boat he's got. I had a 15' Whaler center console I bought
new in 1985. It came with a 70hp, Johnson 2-stroke. Screaming little
boat. He should get good performance with the 60hp, unless the boat is
water-logged.

http://tinyurl.com/yd8r5zl

The propellor specs are in the lower right of the page.

Thanks, John. That's a Bigfoot in the chart. They have a different
gearcase. The numbers are still quite good for a boat like that!

Larry

1976 Boston Whaler Re-power Question
 

In article , says...

"Larry" wrote in message
...
A fishing buddy of mine is re-powering his early 1976 Boston Whaler Sport
15 with a new 60hp 4 stoke Mercury. He is replacing a 2 stroke Mariner
that is an 80's model.

He has no gauges and the layout of the console is like a skiff - the
steering wheel is horizontal. He's not concerned about a speedometer, and
shouldn't be, but I think he should have a tach. The 4 stroke will be
heavier and act differently than the 2 stroke. The props are
interchangeable in size and hub configuration so he plans on putting his
SS prop on the new boat. I'm trying to convince him to find, or make, a
spot for a tach so he can make sure the boat is propped properly (say that
5 times fast!). He's not convinced. The boat is rated for a 75 so the 60
will still weigh about the same as a 75 2 stroke so the transom weight
will be fine.

Has anyone attempted a similar replacement? Should he need a different
prop? Can you attach a tachometer temporarily for testing purposes?

Thanks in advance,
Larry

Sure, you can hook up a tach temporarily, but he may as well do it right.
There is no way he is going to get the prop pitched properly G w/out a
tach. And, he needs one he can see at WOT... not clamped to the transom
"temporarily." It's not a hard gauge to install at all.

---Mike

My VOM (Volt, Ohm meter) has an inductive pickup I can hook on a plug wire and
watch tach. Maybe you can get a cheapo one at Pep Boys or something. Of course
I would first consider the suggestion of others of a permanant one.

Scotty

--
Can I haz Cheezeburger?

1976 Boston Whaler Re-power Question
 

On Thu, 04 Mar 2010 13:36:01 -0500, wrote:

On Wed, 03 Mar 2010 19:58:58 -0500, Larry wrote:

A fishing buddy of mine is re-powering his early 1976 Boston Whaler
Sport 15 with a new 60hp 4 stoke Mercury. He is replacing a 2 stroke
Mariner that is an 80's model.

He has no gauges and the layout of the console is like a skiff - the
steering wheel is horizontal. He's not concerned about a speedometer,
and shouldn't be, but I think he should have a tach. The 4 stroke will
be heavier and act differently than the 2 stroke. The props are
interchangeable in size and hub configuration so he plans on putting his
SS prop on the new boat. I'm trying to convince him to find, or make, a
spot for a tach so he can make sure the boat is propped properly (say
that 5 times fast!). He's not convinced. The boat is rated for a 75 so
the 60 will still weigh about the same as a 75 2 stroke so the transom
weight will be fine.

Has anyone attempted a similar replacement? Should he need a different
prop? Can you attach a tachometer temporarily for testing purposes?

Thanks in advance,
Larry


I made the exact same repower on my boat (Mariner 75 2S to 60 4S Big
Foot)
The weight was close but the prop had to be changed (does he need a
15p, I have one in SS, make offer)
The tach is a 2 wire hookup from the gray wire to ground (port side of
motor) and you could certainly do this temporarily if he can borrow a
tach.
This actually picks up the unrectified output of the charge windings
but there is also an output from the computer. (there are 2 gray wires
on the motor). They both seem to work the same on my motor.
If you just had a meter with a frequency counter you could interpolate
that with a little simple math. Use the idle speed as a sanity check
(700 or so) then see what WOT works out to. You have a pretty wide
"acceptable" range.5500-6000 with the rated HP right in the middle.
I would shoot for close to 6000 with the boat empty. It will always
get heavier as time goes by. ;-)

A '76 Whaler may already be a heavy boat. Lots of foam and wood under the deck
to hold moisture.
--
John H

All decisions are the result of binary thinking,
which is why conservatives can see in black and white.

1976 Boston Whaler Re-power Question
 

mgg wrote:


"Larry" wrote in message
...
A fishing buddy of mine is re-powering his early 1976 Boston Whaler
Sport 15 with a new 60hp 4 stoke Mercury. He is replacing a 2 stroke
Mariner that is an 80's model.

He has no gauges and the layout of the console is like a skiff - the
steering wheel is horizontal. He's not concerned about a
speedometer, and shouldn't be, but I think he should have a tach.
The 4 stroke will be heavier and act differently than the 2 stroke.
The props are interchangeable in size and hub configuration so he
plans on putting his SS prop on the new boat. I'm trying to convince
him to find, or make, a spot for a tach so he can make sure the boat
is propped properly (say that 5 times fast!). He's not convinced.
The boat is rated for a 75 so the 60 will still weigh about the same
as a 75 2 stroke so the transom weight will be fine.

Has anyone attempted a similar replacement? Should he need a
different prop? Can you attach a tachometer temporarily for testing
purposes?

Thanks in advance,
Larry

Sure, you can hook up a tach temporarily, but he may as well do it
right. There is no way he is going to get the prop pitched properly
G w/out a tach. And, he needs one he can see at WOT... not clamped
to the transom "temporarily." It's not a hard gauge to install at all.

---Mike
I agree. He's had the Mariner forever and it's worked fine. He doesn't
think the 4 stroke in the same size will be much different.

Thanks,
Larry

1976 Boston Whaler Re-power Question
 

I am Tosk wrote:
In , says...

wrote in message
...

A fishing buddy of mine is re-powering his early 1976 Boston Whaler Sport
15 with a new 60hp 4 stoke Mercury. He is replacing a 2 stroke Mariner
that is an 80's model.

He has no gauges and the layout of the console is like a skiff - the
steering wheel is horizontal. He's not concerned about a speedometer, and
shouldn't be, but I think he should have a tach. The 4 stroke will be
heavier and act differently than the 2 stroke. The props are
interchangeable in size and hub configuration so he plans on putting his
SS prop on the new boat. I'm trying to convince him to find, or make, a
spot for a tach so he can make sure the boat is propped properly (say that
5 times fast!). He's not convinced. The boat is rated for a 75 so the 60
will still weigh about the same as a 75 2 stroke so the transom weight
will be fine.

Has anyone attempted a similar replacement? Should he need a different
prop? Can you attach a tachometer temporarily for testing purposes?

Thanks in advance,
Larry

Sure, you can hook up a tach temporarily, but he may as well do it right.
There is no way he is going to get the prop pitched properlyG w/out a
tach. And, he needs one he can see at WOT... not clamped to the transom
"temporarily." It's not a hard gauge to install at all.

---Mike

My VOM (Volt, Ohm meter) has an inductive pickup I can hook on a plug wire and
watch tach. Maybe you can get a cheapo one at Pep Boys or something. Of course
I would first consider the suggestion of others of a permanant one.

Scotty


If I can't convince him to install a permanent tach, that is a good
alternative.

Thanks,
Larry

1976 Boston Whaler Re-power Question
 

1976 Boston Whaler Re-power Question
 

John H wrote:
On Thu, 04 Mar 2010 13:36:01 -0500, wrote:


On Wed, 03 Mar 2010 19:58:58 -0500, wrote:


A fishing buddy of mine is re-powering his early 1976 Boston Whaler
Sport 15 with a new 60hp 4 stoke Mercury. He is replacing a 2 stroke
Mariner that is an 80's model.

He has no gauges and the layout of the console is like a skiff - the
steering wheel is horizontal. He's not concerned about a speedometer,
and shouldn't be, but I think he should have a tach. The 4 stroke will
be heavier and act differently than the 2 stroke. The props are
interchangeable in size and hub configuration so he plans on putting his
SS prop on the new boat. I'm trying to convince him to find, or make, a
spot for a tach so he can make sure the boat is propped properly (say
that 5 times fast!). He's not convinced. The boat is rated for a 75 so
the 60 will still weigh about the same as a 75 2 stroke so the transom
weight will be fine.

Has anyone attempted a similar replacement? Should he need a different
prop? Can you attach a tachometer temporarily for testing purposes?

Thanks in advance,
Larry


I made the exact same repower on my boat (Mariner 75 2S to 60 4S Big
Foot)
The weight was close but the prop had to be changed (does he need a
15p, I have one in SS, make offer)
The tach is a 2 wire hookup from the gray wire to ground (port side of
motor) and you could certainly do this temporarily if he can borrow a
tach.
This actually picks up the unrectified output of the charge windings
but there is also an output from the computer. (there are 2 gray wires
on the motor). They both seem to work the same on my motor.
If you just had a meter with a frequency counter you could interpolate
that with a little simple math. Use the idle speed as a sanity check
(700 or so) then see what WOT works out to. You have a pretty wide
"acceptable" range.5500-6000 with the rated HP right in the middle.
I would shoot for close to 6000 with the boat empty. It will always
get heavier as time goes by. ;-)

A '76 Whaler may already be a heavy boat. Lots of foam and wood under the deck
to hold moisture.

It's been babied and stored well. It's quite light for a boat that
size. I was surprised the first time I was on it.

Larry