This is a long post, but bear with me, I will eventually get to the
point. There's just a lot of background to fill you in on.

I have a '64 9.5 HP Johnson outboard that gets used heavily on a 14-ft.
aluminum boat during a one week vacation each year on the St. Lawrence
Seaway. The rest of the time it sits idle, hanging on a stand or on a
wall, waiting for my next fishing opportunity. I originally got it for
free in 1986 from my sister-in-law's father, with a cracked block. By
the time I was done with her, I'd purchased a used block, one new piston
and rings, new gaskets, and a new crankshaft. It ran like a top, often
starting on the third or fourth pull when I got it out of storage, and
almost always on the first one until I put it back in storage. All it
ever needed was a periodic changing of the lower unit oil, and some
points maintenance.

Then came last year, and the honeymoon was over. It was my own fault,
too. One day while trying to launch by myself on a rather windy day, the
wind blew me back onto some rocks before I could do anything about it.
That tore up the rubber shock bushing in the prop. Naturally, the local
OMC dealer, about an hour away, was the only place to get one. According
to a book I have, the original prop was an 8 1/8 x 8 inch. All the
dealer had that would fit was an 8 1/4 x 9 inch. It was either that or
ruin vacation, so I bought it.

But that's not all that happened. I put the new prop on and it seemed to
work ok, despite being "bigger" than the original, but it wasn't really
the kind of day when one can test performance. The next day I was out
fishing with my mother, when the water pump impeller decided to give up.
It was at the most inconvenient time, too (Is there a GOOD time for
it???) - when I had to keep running it to get out of the way of
God-knows-how-many-tons of freighter. (Hey, there's nice smallmouths in
that shipping channel, but you just don't argue with one of those guys.)
I got out of the way, but I had to run the ol' Johnson until the pistons
seized to do it.

That made me physically ill. I was sure the ol' girl was a goner, but
after being towed in, allowing it to cool, checking things like the
points and compression, I tried it and it started! Ran nice and smooth,
too - for what little time I let it. Then it was back off, pull the
lower unit apart, and another two-hour round trip to the OMC dealer for
an impeller. I put it back together and ran it the rest of the vacation
on our second boat - the one my mother *doesn't* use. (Trust me - I
didn't want any more breakdowns with her in the boat.) It ran fine once
it started, but now it would take at least three or four pulls to start
it every time, and sometimes you had to choke it in the middle of the
day - unheard of before. Didn't quite have the zip it had before, either
- but I put most of that to the different boat. I was just so overjoyed
that it even ran that I wasn't about to complain.

Then came this year. When I brought it out of storage, it took 12-15
pulls to get it to start the first time. Every time thereafter it took
at least three. The power wasn't there, either. It was only about 3/4 of
what it was before. It still ran smoothly, though, and if I hadn't known
what it was capable of, I might not have thought anything was wrong -
until the last day. On that one, it started misfiring, and it ran like
it was half a motor.

So I'm thinking some major work is in order this winter. I suspect a
modest crankcase leak. I'm considering new rings, head gasket, and
crankshaft seals. New plug wires probably wouldn't be a bad idea,
either. They're still the originals. New plugs, too - those plugs are
the ones that went through the heat stroke. (I think that last day
misfiring could well be a plug going bad.) I toyed with the idea of new
bearings, but I think that if they were bad that would have shown up
catastrophically during this year's vacation.

I have two questions. Is there anything else I should be looking at?
And, how much of the poorer performance could be attributed to the
"bigger" prop? (meaning, should I buy one closer to original specs?)

TJ

On Aug 11, 9:47*pm, TJ wrote:
This is a long post, but bear with me, I will eventually get to the
point. There's just a lot of background to fill you in on.

I have a '64 9.5 HP Johnson outboard that gets used heavily on a 14-ft.
aluminum boat during a one week vacation each year on the St. Lawrence
Seaway. The rest of the time it sits idle, hanging on a stand or on a
wall, waiting for my next fishing opportunity. I originally got it for
free in 1986 from my sister-in-law's father, with a cracked block. By
the time I was done with her, I'd purchased a used block, one new piston
and rings, new gaskets, and a new crankshaft. It ran like a top, often
starting on the third or fourth pull when I got it out of storage, and
almost always on the first one until I put it back in storage. All it
ever needed was a periodic changing of the lower unit oil, and some
points maintenance.

Then came last year, and the honeymoon was over. It was my own fault,
too. One day while trying to launch by myself on a rather windy day, the
wind blew me back onto some rocks before I could do anything about it.
That tore up the rubber shock bushing in the prop. Naturally, the local
OMC dealer, about an hour away, was the only place to get one. According
to a book I have, the original prop was an 8 1/8 x 8 inch. All the
dealer had that would fit was an 8 1/4 x 9 inch. It was either that or
ruin vacation, so I bought it.

But that's not all that happened. I put the new prop on and it seemed to
work ok, despite being "bigger" than the original, but it wasn't really
the kind of day when one can test performance. The next day I was out
fishing with my mother, when the water pump impeller decided to give up.
It was at the most inconvenient time, too (Is there a GOOD time for
it???) - when I had to keep running it to get out of the way of
God-knows-how-many-tons of freighter. (Hey, there's nice smallmouths in
that shipping channel, but you just don't argue with one of those guys.)
I got out of the way, but I had to run the ol' Johnson until the pistons
seized to do it.

That made me physically ill. I was sure the ol' girl was a goner, but
after being towed in, allowing it to cool, checking things like the
points and compression, I tried it and it started! Ran nice and smooth,
too - for what little time I let it. Then it was back off, pull the
lower unit apart, and another two-hour round trip to the OMC dealer for
an impeller. I put it back together and ran it the rest of the vacation
on our second boat - the one my mother *doesn't* use. (Trust me - I
didn't want any more breakdowns with her in the boat.) It ran fine once
it started, but now it would take at least three or four pulls to start
it every time, and sometimes you had to choke it in the middle of the
day - unheard of before. Didn't quite have the zip it had before, either
- but I put most of that to the different boat. I was just so overjoyed
that it even ran that I wasn't about to complain.

Then came this year. When I brought it out of storage, it took 12-15
pulls to get it to start the first time. Every time thereafter it took
at least three. The power wasn't there, either. It was only about 3/4 of
what it was before. It still ran smoothly, though, and if I hadn't known
what it was capable of, I might not have thought anything was wrong -
until the last day. On that one, it started misfiring, and it ran like
it was half a motor.

So I'm thinking some major work is in order this winter. I suspect a
modest crankcase leak. I'm considering new rings, head gasket, and
crankshaft seals. New plug wires probably wouldn't be a bad idea,
either. They're still the originals. New plugs, too - those plugs are
the ones that went through the heat stroke. (I think that last day
misfiring could well be a plug going bad.) I toyed with the idea of new
bearings, but I think that if they were bad that would have shown up
catastrophically during this year's vacation.

I have two questions. Is there anything else I should be looking at?
And, how much of the poorer performance could be attributed to the
"bigger" prop? (meaning, should I buy one closer to original specs?)

TJ

Don't knwo about the prop, but it shouldn't make that much of a
difference I wouldn't think. but then again it's only 9.5 hp. and it
could make it suffer a little, but I really don't think so. If you
still ahve the old prop, you can probably have it rebuilt. There'sw
lots of good specialy shops that do that kind of work for less than
buying a new prop. But still i wouldn't think that size prop would be
expensive new.

concerning crank case leakage, you're probably correct. maybe a score
in a cylinder and piston. But also if you got it hot enough to lock,
it's possible your crank seals are damaged. I dont' know that for a
fact, but I'm kind of familiar with bad seals on old 2 cycle
motorcycles and an old lawnboy mower (also AMC).

Thaks all I can say, besides "good luck"

On Mon, 11 Aug 2008 22:47:11 -0400, TJ wrote:

I have two questions. Is there anything else I should be looking at?
And, how much of the poorer performance could be attributed to the
"bigger" prop? (meaning, should I buy one closer to original specs?)

I suspect your problem is related to cooking the engine rather than
the prop. That impeller was getting ready to go and when it did,
given the situation, it cooked everything.

Truthfully, that engine may be a goner. Even assuming that you have
access to parts for that engine, you probably scored the pistons
pretty good and after all these years, there might not be a lot of
room left for new rings/pistons. Good luck with that though.

With respect to the prop, if you have the original (I forgot if you
did or didn't), that can be rebuilt easily - there are plenty of
rebuild shops around that can handle that.

"TJ" wrote in message
...
This is a long post, but bear with me, I will eventually get to the point.
There's just a lot of background to fill you in on.

I have a '64 9.5 HP Johnson outboard that gets used heavily on a 14-ft.
aluminum boat during a one week vacation each year on the St. Lawrence
Seaway. The rest of the time it sits idle, hanging on a stand or on a
wall, waiting for my next fishing opportunity. I originally got it for
free in 1986 from my sister-in-law's father, with a cracked block. By the
time I was done with her, I'd purchased a used block, one new piston and
rings, new gaskets, and a new crankshaft. It ran like a top, often
starting on the third or fourth pull when I got it out of storage, and
almost always on the first one until I put it back in storage. All it ever
needed was a periodic changing of the lower unit oil, and some points
maintenance.

Then came last year, and the honeymoon was over. It was my own fault, too.
One day while trying to launch by myself on a rather windy day, the wind
blew me back onto some rocks before I could do anything about it. That
tore up the rubber shock bushing in the prop. Naturally, the local OMC
dealer, about an hour away, was the only place to get one. According to a
book I have, the original prop was an 8 1/8 x 8 inch. All the dealer had
that would fit was an 8 1/4 x 9 inch. It was either that or ruin vacation,
so I bought it.

But that's not all that happened. I put the new prop on and it seemed to
work ok, despite being "bigger" than the original, but it wasn't really
the kind of day when one can test performance. The next day I was out
fishing with my mother, when the water pump impeller decided to give up.
It was at the most inconvenient time, too (Is there a GOOD time for
it???) - when I had to keep running it to get out of the way of
God-knows-how-many-tons of freighter. (Hey, there's nice smallmouths in
that shipping channel, but you just don't argue with one of those guys.) I
got out of the way, but I had to run the ol' Johnson until the pistons
seized to do it.

That made me physically ill. I was sure the ol' girl was a goner, but
after being towed in, allowing it to cool, checking things like the points
and compression, I tried it and it started! Ran nice and smooth, too - for
what little time I let it. Then it was back off, pull the lower unit
apart, and another two-hour round trip to the OMC dealer for an impeller.
I put it back together and ran it the rest of the vacation on our second
boat - the one my mother *doesn't* use. (Trust me - I didn't want any more
breakdowns with her in the boat.) It ran fine once it started, but now it
would take at least three or four pulls to start it every time, and
sometimes you had to choke it in the middle of the day - unheard of
before. Didn't quite have the zip it had before, either - but I put most
of that to the different boat. I was just so overjoyed that it even ran
that I wasn't about to complain.

Then came this year. When I brought it out of storage, it took 12-15 pulls
to get it to start the first time. Every time thereafter it took at least
three. The power wasn't there, either. It was only about 3/4 of what it
was before. It still ran smoothly, though, and if I hadn't known what it
was capable of, I might not have thought anything was wrong - until the
last day. On that one, it started misfiring, and it ran like it was half a
motor.

So I'm thinking some major work is in order this winter. I suspect a
modest crankcase leak. I'm considering new rings, head gasket, and
crankshaft seals. New plug wires probably wouldn't be a bad idea, either.
They're still the originals. New plugs, too - those plugs are the ones
that went through the heat stroke. (I think that last day misfiring could
well be a plug going bad.) I toyed with the idea of new bearings, but I
think that if they were bad that would have shown up catastrophically
during this year's vacation.

I have two questions. Is there anything else I should be looking at? And,
how much of the poorer performance could be attributed to the "bigger"
prop? (meaning, should I buy one closer to original specs?)

TJ

My thought would be that seizing it damaged the piston/cylinder and possibly
the seals as well. Pull the top end and take a look at the cylinder wall to
see if you can get by with a piston/rings or if you need a whole new top
end. It's not unusual for seized 2 strokes to run again after cooling down
but they seldom are ever the same. When's the last time you had replaced
the impeller?

jamesgangnc wrote:

My thought would be that seizing it damaged the piston/cylinder and possibly
the seals as well. Pull the top end and take a look at the cylinder wall to
see if you can get by with a piston/rings or if you need a whole new top
end. It's not unusual for seized 2 strokes to run again after cooling down
but they seldom are ever the same. When's the last time you had replaced
the impeller?


I didn't, because I kept seeing water coming out the pee hole. That's
part of why it's my own fault. I knew better.

The cylinder head is easy enough to pull without taking the thing out of
that clamshell case, so I guess I need to do that before thinking much
more. The parts list indicates they had .020 and .040 oversized piston
and ring sets available, though they would probably be next to
impossible to find any more now. But, you never know. Somebody might
have some gathering dust on a shelf somewhere. In any case, that would
seem to indicate that the standard piston/rings are good to .010 over
size, at least. Perhaps if the scoring isn't very bad a bit of machining
would help. I own a farm, and have been known to rebuild an engine or
two in my time. Trouble is, most of my experience is with four-strokes
in tractors and combines.

This old motor and I have been through a lot of good times together, and
I really hate the idea of giving up on her without a fight. Between now
and the end of the growing season, though, I have to spend my time
making a living.

TJ

"TJ" wrote in message
...
jamesgangnc wrote:

My thought would be that seizing it damaged the piston/cylinder and
possibly the seals as well. Pull the top end and take a look at the
cylinder wall to see if you can get by with a piston/rings or if you need
a whole new top end. It's not unusual for seized 2 strokes to run again
after cooling down but they seldom are ever the same. When's the last
time you had replaced the impeller?
I didn't, because I kept seeing water coming out the pee hole. That's part
of why it's my own fault. I knew better.

The cylinder head is easy enough to pull without taking the thing out of
that clamshell case, so I guess I need to do that before thinking much
more. The parts list indicates they had .020 and .040 oversized piston and
ring sets available, though they would probably be next to impossible to
find any more now. But, you never know. Somebody might have some gathering
dust on a shelf somewhere. In any case, that would seem to indicate that
the standard piston/rings are good to .010 over size, at least. Perhaps if
the scoring isn't very bad a bit of machining would help. I own a farm,
and have been known to rebuild an engine or two in my time. Trouble is,
most of my experience is with four-strokes in tractors and combines.

This old motor and I have been through a lot of good times together, and I
really hate the idea of giving up on her without a fight. Between now and
the end of the growing season, though, I have to spend my time making a
living.

TJ

Yea, you've got no one but yourself to blame if you tried to get 20 years
out a rubber impeller.

That they only have 20 and 40 over does not indicate that you can use a
standard piston in a 10 over hole. A 2 stroke will have hgiher clearance
built into the piston size already. If it needs boring to remove scoring
then you need to find a 20 or 40 over piston. That would be the next thing
to research after you take a look at the cylinder. You might be surprised
about the piston. Some of those smaller engines were built in various
configuations using the same pistons for a long time. You might also find a
use top end somewhere but after this many years the chances of any not being
pretty worn out are slim.

jamesgangnc wrote:
"TJ" wrote in message
...
jamesgangnc wrote:

My thought would be that seizing it damaged the piston/cylinder and
possibly the seals as well. Pull the top end and take a look at the
cylinder wall to see if you can get by with a piston/rings or if you need
a whole new top end. It's not unusual for seized 2 strokes to run again
after cooling down but they seldom are ever the same. When's the last
time you had replaced the impeller?
I didn't, because I kept seeing water coming out the pee hole. That's part
of why it's my own fault. I knew better.

The cylinder head is easy enough to pull without taking the thing out of
that clamshell case, so I guess I need to do that before thinking much
more. The parts list indicates they had .020 and .040 oversized piston and
ring sets available, though they would probably be next to impossible to
find any more now. But, you never know. Somebody might have some gathering
dust on a shelf somewhere. In any case, that would seem to indicate that
the standard piston/rings are good to .010 over size, at least. Perhaps if
the scoring isn't very bad a bit of machining would help. I own a farm,
and have been known to rebuild an engine or two in my time. Trouble is,
most of my experience is with four-strokes in tractors and combines.

This old motor and I have been through a lot of good times together, and I
really hate the idea of giving up on her without a fight. Between now and
the end of the growing season, though, I have to spend my time making a
living.

TJ

Yea, you've got no one but yourself to blame if you tried to get 20 years
out a rubber impeller.

That they only have 20 and 40 over does not indicate that you can use a
standard piston in a 10 over hole. A 2 stroke will have hgiher clearance
built into the piston size already. If it needs boring to remove scoring
then you need to find a 20 or 40 over piston. That would be the next thing
to research after you take a look at the cylinder. You might be surprised
about the piston. Some of those smaller engines were built in various
configuations using the same pistons for a long time. You might also find a
use top end somewhere but after this many years the chances of any not being
pretty worn out are slim.


So far, it looks like I've lucked out. The cylinder walls feel and look
as smooth as a baby's bottom. One wall had more oil on it than the
other, indicating it was the one that was misfiring that last day,
August 2nd. The center electrode of the plug from that cylinder looked
like it had recently broken off down near the insulator, so I suspect
that was the reason for the misfiring. I do see the slightest bit of
scuffing, barely discernible, on the bottom of the top cylinder, but who
knows how long that's been there. Both pistons can be rocked back and
forth a bit, indicating at the least worn rings, and probably worn
pistons. But then, I'd expect that after 20 years, even using it for a
week a year, and as you said, they have higher clearances built-in. One
of those pistons is 44 years old.

I'm still thinking new rings and new plugs will restore most of the
power, and I should replace the crankshaft seals simply because they're
rubber too, are also 22 years old, and have been exposed to that heat.

Then again, I also have a '54 10-horse that's never had the crank seals
or piston rings replaced, and it runs like a scared cat. That's the
motor that normally runs our second boat. Seeing as I've had that one
for 10 years, maybe it would be a good idea to replace that impeller
while I'm in the process of ordering parts, too. :^)

TJ

On Tue, 12 Aug 2008 11:22:03 -0400, TJ wrote:

jamesgangnc wrote:
"TJ" wrote in message
...
jamesgangnc wrote:

My thought would be that seizing it damaged the piston/cylinder and
possibly the seals as well. Pull the top end and take a look at the
cylinder wall to see if you can get by with a piston/rings or if you need
a whole new top end. It's not unusual for seized 2 strokes to run again
after cooling down but they seldom are ever the same. When's the last
time you had replaced the impeller?
I didn't, because I kept seeing water coming out the pee hole. That's part
of why it's my own fault. I knew better.

The cylinder head is easy enough to pull without taking the thing out of
that clamshell case, so I guess I need to do that before thinking much
more. The parts list indicates they had .020 and .040 oversized piston and
ring sets available, though they would probably be next to impossible to
find any more now. But, you never know. Somebody might have some gathering
dust on a shelf somewhere. In any case, that would seem to indicate that
the standard piston/rings are good to .010 over size, at least. Perhaps if
the scoring isn't very bad a bit of machining would help. I own a farm,
and have been known to rebuild an engine or two in my time. Trouble is,
most of my experience is with four-strokes in tractors and combines.

This old motor and I have been through a lot of good times together, and I
really hate the idea of giving up on her without a fight. Between now and
the end of the growing season, though, I have to spend my time making a
living.

TJ

Yea, you've got no one but yourself to blame if you tried to get 20 years
out a rubber impeller.

That they only have 20 and 40 over does not indicate that you can use a
standard piston in a 10 over hole. A 2 stroke will have hgiher clearance
built into the piston size already. If it needs boring to remove scoring
then you need to find a 20 or 40 over piston. That would be the next thing
to research after you take a look at the cylinder. You might be surprised
about the piston. Some of those smaller engines were built in various
configuations using the same pistons for a long time. You might also find a
use top end somewhere but after this many years the chances of any not being
pretty worn out are slim.


So far, it looks like I've lucked out. The cylinder walls feel and look
as smooth as a baby's bottom. One wall had more oil on it than the
other, indicating it was the one that was misfiring that last day,
August 2nd. The center electrode of the plug from that cylinder looked
like it had recently broken off down near the insulator, so I suspect
that was the reason for the misfiring. I do see the slightest bit of
scuffing, barely discernible, on the bottom of the top cylinder, but who
knows how long that's been there. Both pistons can be rocked back and
forth a bit, indicating at the least worn rings, and probably worn
pistons. But then, I'd expect that after 20 years, even using it for a
week a year, and as you said, they have higher clearances built-in. One
of those pistons is 44 years old.

I'm still thinking new rings and new plugs will restore most of the
power, and I should replace the crankshaft seals simply because they're
rubber too, are also 22 years old, and have been exposed to that heat.

Then again, I also have a '54 10-horse that's never had the crank seals
or piston rings replaced, and it runs like a scared cat. That's the
motor that normally runs our second boat. Seeing as I've had that one
for 10 years, maybe it would be a good idea to replace that impeller
while I'm in the process of ordering parts, too. :^)

TJ

Sounds like a plan. Hope it all works!

"TJ" wrote in message
...
jamesgangnc wrote:
"TJ" wrote in message
...
jamesgangnc wrote:

My thought would be that seizing it damaged the piston/cylinder and
possibly the seals as well. Pull the top end and take a look at the
cylinder wall to see if you can get by with a piston/rings or if you
need a whole new top end. It's not unusual for seized 2 strokes to run
again after cooling down but they seldom are ever the same. When's the
last time you had replaced the impeller?
I didn't, because I kept seeing water coming out the pee hole. That's
part of why it's my own fault. I knew better.

The cylinder head is easy enough to pull without taking the thing out of
that clamshell case, so I guess I need to do that before thinking much
more. The parts list indicates they had .020 and .040 oversized piston
and ring sets available, though they would probably be next to
impossible to find any more now. But, you never know. Somebody might
have some gathering dust on a shelf somewhere. In any case, that would
seem to indicate that the standard piston/rings are good to .010 over
size, at least. Perhaps if the scoring isn't very bad a bit of machining
would help. I own a farm, and have been known to rebuild an engine or
two in my time. Trouble is, most of my experience is with four-strokes
in tractors and combines.

This old motor and I have been through a lot of good times together, and
I really hate the idea of giving up on her without a fight. Between now
and the end of the growing season, though, I have to spend my time
making a living.

TJ

Yea, you've got no one but yourself to blame if you tried to get 20 years
out a rubber impeller.

That they only have 20 and 40 over does not indicate that you can use a
standard piston in a 10 over hole. A 2 stroke will have hgiher clearance
built into the piston size already. If it needs boring to remove scoring
then you need to find a 20 or 40 over piston. That would be the next
thing to research after you take a look at the cylinder. You might be
surprised about the piston. Some of those smaller engines were built in
various configuations using the same pistons for a long time. You might
also find a use top end somewhere but after this many years the chances
of any not being pretty worn out are slim.


So far, it looks like I've lucked out. The cylinder walls feel and look as
smooth as a baby's bottom. One wall had more oil on it than the other,
indicating it was the one that was misfiring that last day, August 2nd.
The center electrode of the plug from that cylinder looked like it had
recently broken off down near the insulator, so I suspect that was the
reason for the misfiring. I do see the slightest bit of scuffing, barely
discernible, on the bottom of the top cylinder, but who knows how long
that's been there. Both pistons can be rocked back and forth a bit,
indicating at the least worn rings, and probably worn pistons. But then,
I'd expect that after 20 years, even using it for a week a year, and as
you said, they have higher clearances built-in. One of those pistons is 44
years old.

I'm still thinking new rings and new plugs will restore most of the power,
and I should replace the crankshaft seals simply because they're rubber
too, are also 22 years old, and have been exposed to that heat.

Then again, I also have a '54 10-horse that's never had the crank seals or
piston rings replaced, and it runs like a scared cat. That's the motor
that normally runs our second boat. Seeing as I've had that one for 10
years, maybe it would be a good idea to replace that impeller while I'm in
the process of ordering parts, too. :^)

TJ


Preventive maintenance...that's what it's all about.

On Aug 12, 10:22*am, TJ wrote:
jamesgangnc wrote:
"TJ" wrote in message
...
jamesgangnc wrote:

My thought would be that seizing it damaged the piston/cylinder and
possibly the seals as well. *Pull the top end and take a look at the
cylinder wall to see if you can get by with a piston/rings or if you need
a whole new top end. *It's not unusual for seized 2 strokes to run again
after cooling down but they seldom are ever the same. *When's the last
time you had replaced the impeller?
I didn't, because I kept seeing water coming out the pee hole. That's part
of why it's my own fault. I knew better.

The cylinder head is easy enough to pull without taking the thing out of
that clamshell case, so I guess I need to do that before thinking much
more. The parts list indicates they had .020 and .040 oversized piston and
ring sets available, though they would probably be next to impossible to
find any more now. But, you never know. Somebody might have some gathering
dust on a shelf somewhere. In any case, that would seem to indicate that
the standard piston/rings are good to .010 over size, at least. Perhaps if
the scoring isn't very bad a bit of machining would help. I own a farm,
and have been known to rebuild an engine or two in my time. Trouble is,
most of my experience is with four-strokes in tractors and combines.

This old motor and I have been through a lot of good times together, and I
really hate the idea of giving up on her without a fight. Between now and
the end of the growing season, though, I have to spend my time making a
living.

TJ

Yea, you've got no one but yourself to blame if you tried to get 20 years
out a rubber impeller.

That they only have 20 and 40 over does not indicate that you can use a
standard piston in a 10 over hole. *A 2 stroke will have hgiher clearance
built into the piston size already. *If it needs boring to remove scoring
then you need to find a 20 or 40 over piston. *That would be the next thing
to research after you take a look at the cylinder. *You might be surprised
about the piston. *Some of those smaller engines were built in various
configuations using the same pistons for a long time. *You might also find a
use top end somewhere but after this many years the chances of any not being
pretty worn out are slim.

So far, it looks like I've lucked out. The cylinder walls feel and look
as smooth as a baby's bottom. One wall had more oil on it than the
other, indicating it was the one that was misfiring that last day,
August 2nd. The center electrode of the plug from that cylinder looked
like it had recently broken off down near the insulator, so I suspect
that was the reason for the misfiring. I do see the slightest bit of
scuffing, barely discernible, on the bottom of the top cylinder, but who
knows how long that's been there. Both pistons can be rocked back and
forth a bit, indicating at the least worn rings, and probably worn
pistons. But then, I'd expect that after 20 years, even using it for a
week a year, and as you said, they have higher clearances built-in. One
of those pistons is 44 years old.

I'm still thinking new rings and new plugs will restore most of the
power, and I should replace the crankshaft seals simply because they're
rubber too, are also 22 years old, and have been exposed to that heat.

Then again, I also have a '54 10-horse that's never had the crank seals
or piston rings replaced, and it runs like a scared cat. That's the
motor that normally runs our second boat. Seeing as I've had that one
for 10 years, maybe it would be a good idea to replace that impeller
while I'm in the process of ordering parts, too. :^)

TJ- Hide quoted text -

- Show quoted text -

If anything else, scrounge around on ebay. there's still OEM parts
available for those engines if you know what to look for. Some at
very reasonable prices, too!