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steamer November 22nd 06 05:54 PM

Speaking of outboards...
 
--I'm looking for an old outboard; preferably a 3-cylinder engine
*without* an overhead camshaft. I don't suppose anyone knows where I could
find such do they? And yes, I plan to convert it to steam, hehe.

--
"Steamboat Ed" Haas : Why do weekend projects
Hacking the Trailing Edge! : always last a month??
www.nmpproducts.com
---Decks a-wash in a sea of words---

Matt Colie November 22nd 06 09:04 PM

Speaking of outboards...
 
Ed,

There are a whole lot of three cylinder outboards without camshafts out
there, but they are all 2-stroke. Even if you are planing to make it a
single acting uniflow, you may have trouble with the exhaust port height.

Given that you won't have to cool it, you could make this work by
sleaving the it so it can still use a stock piston. Then you can put
the exhaust pots where you want them and then you only need to make a
new cylinder head and camshaft pair and linking drive.

Good Luck

Matt Colie

steamer wrote:
--I'm looking for an old outboard; preferably a 3-cylinder engine
*without* an overhead camshaft. I don't suppose anyone knows where I could
find such do they? And yes, I plan to convert it to steam, hehe.


steamer November 22nd 06 11:00 PM

Speaking of outboards...
 
Matt Colie wrote:
Ed,


There are a whole lot of three cylinder outboards without camshafts out
there, but they are all 2-stroke. Even if you are planing to make it a
single acting uniflow, you may have trouble with the exhaust port height.

--Fixable.

Given that you won't have to cool it, you could make this work by
sleaving the it so it can still use a stock piston. Then you can put
the exhaust pots where you want them and then you only need to make a
new cylinder head and camshaft pair and linking drive.

--Hmmm neat idea. Got any pointers to make/models to look for?
Complete novice here..

--
"Steamboat Ed" Haas : Why do weekend projects
Hacking the Trailing Edge! : always last a month??
www.nmpproducts.com
---Decks a-wash in a sea of words---

Matt Colie November 23rd 06 12:56 AM

Speaking of outboards...
 
Ed,
I started answering you thinking of how one might do this to a 2-stroke
(there being many more than 4-stroke), but I missed some things.

The lower end lubrication could be and issue with adapting a 2-stroke.
There is no lube oil pump at all, but most are needle bearing so they
need no supply pressure, just a more or less continues supply, but there
is also no postive supply to the rod bearing as this was designed to be
swimming in the fuel/lube mix. If you can work around that you will
have to planning on the sleave trick if you can figure out how to oil it
all effectively because the intake ports open to the crankcase.

The OMC 50-55-60 HP engines were 3 cylinder depending on the year
build. There are a lot of them out there and you don't care if someone
got the mix wrong and scuffed a bore (I fact you might be hoping for one.)

Skinner Uniflows used two camshafts that could shifted 90deg to run
astern and the reationship of the two cams controlled the angle of
admission (their version of linking down). I will have to start
searching up old text books to tell you much more than that. I wouldn't
mind so very much, but my study is about to get relocated in the house
and most of my books are packed i crates and will be so for an
unspecified time.

Matt Colie


steamer wrote:
Matt Colie wrote:

Ed,



There are a whole lot of three cylinder outboards without camshafts out
there, but they are all 2-stroke. Even if you are planing to make it a
single acting uniflow, you may have trouble with the exhaust port height.


--Fixable.


Given that you won't have to cool it, you could make this work by
sleaving the it so it can still use a stock piston. Then you can put
the exhaust pots where you want them and then you only need to make a
new cylinder head and camshaft pair and linking drive.


--Hmmm neat idea. Got any pointers to make/models to look for?
Complete novice here..



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