"Matt Koch" wrote in message ...
For what it's worth, I also have a yanmar single cylinder engine in my boat,
a YSE8.

At idle it is also very rouogh and loud, I also get a little oil coming out
fo rthe wxhasut when its cold and I have the black transom syndrome. I have
had the injector tested and adjusted but still get the black moustache.

Cheers

Matt
"Rich Hampel" wrote in message
...
In article , Guillermo
wrote:


- The engine runs very rough at idle. If I open the engine
compartment I can see the engine moving quite a bit and hear a big
"tok" "tok". I was told this was normal, however still concerns me.
Any ideas?
Completely normal for a single cylinder diesel engine idle ... you will
also find one or two 'nodes' at higher rpm where this may also happen.

- Also, sometimes, after the engine first starts I can see quite a bit
of oil coming out the exhaust pipe and quite a bit of smoke (dark).
This goes away after a few minutes of operation. Any ideas?
Engine combustion chamber isnt hot enough for complete combustion ....
complete combustion will occur once combustion chamber fully comes up
to operating temperature.

- After running the engine for several hours, I notice that my transom
has black oil stains. The boat I have (C&C 27) has the exhaust pipe
coming out the transom a bit above the water line, so I guess any oil
coming out the pipe stays in the whirlpool. Is this normal?
Yup, At the end of the season, you might want to remove the fuel
injector and take it to a specialized autonmotve shop that concentrates
on rebuilding injectors (gas and diesel). The injector specialist will
test the injector and see if it needs adjustment or rebuilding -
oil on the transom.
:-)

Thanks in advance.
Guillermo

I had a 1GM (7 hp) in my S2 and what you describe sounds normal.
However, the black smoke might also indicate it is under too much load
from a fouled prop. My 1GM was the most amazingly reliable engine I
have ever seen. Unfortunately, its 6.5 hp was really too little for
an 8000 lb boat so after 20 yrs, I replaced it with a 2GM (13 hp).
Also check for exhaust blockage that can overload the engine.
Does it come up to normal RPM? The RPM sensor on the flywheel can
corrode so it reads wrong so be careful here.
These engines sound like the African Queen and vibrate a lot in
certain RPM ranges. Mine had a broken engine mount for years but this
was never a problem.