I have got a used boat with a 1995 Mercury 115HP 2-stroke motor on it.
The motor has an oil-injection-system. This means in theory I don't
need to mix oil with fuel. But when I examine the fuel in the boat, I
find that the ex-owner has already mixed oil into the fuel. I am
wondering if the oil-injection-system really works or not. I would
like to find a way to check if the oil-injection-system works or not.

I supposed I can run the boat and keep an eye at the oil level in the
oil reservoir (knowing that the fuel already has oil and I don't need
to worry about running the motor without oil). If the oil level
gradually drop, this means the oil-injection-system seems to be
working, and I can feel free to add fuel without pre-mixing with oil.
If the oil level stands still, this means the oil-injection-system
fails, and I should pre-mix with oil and have the motor serviced. Does
this sound right?

And yes I need to carry more spare spark plus because the motor will be
running very rich with oil.

Thanks.

Jay Chan

You're a new boater as I have seen you ask many questions in this forum lately.

If I were you, I'd take the thing in to a Mercury mechanic and have them
check it out. Why run the risk of seizing the engine should the injection
system not be working?

For the peace of mind of it all, why not just have someone who knows the
engine take a look at it? You've worked too hard to get to this point.

barry

Well said. And while you're at it, have them change the water pump
impeller. Unless you know for sure it is less than 3 years old, you should
change it to be certain it is fresh. This is a wear prone part and the
price of leaving it too long is engine overheating and possible meltdown.

--
Denis Roy
D. Roy Woodcraft
www.ideasinwood.com
wrote in message
roups.com...

You're a new boater as I have seen you ask many questions in this forum
lately.

If I were you, I'd take the thing in to a Mercury mechanic and have them
check it out. Why run the risk of seizing the engine should the injection
system not be working?

For the peace of mind of it all, why not just have someone who knows the
engine take a look at it? You've worked too hard to get to this point.

barry

Well said. And while you're at it, have them change the water pump
impeller. Unless you know for sure it is less than 3 years old, you should
change it to be certain it is fresh. This is a wear prone part and the
price of leaving it too long is engine overheating and possible meltdown.

Because I will bring the motor in for service/maintenance, I will ask
them to replace the water pump impeller. Thanks for the suggestion.

Jay Chan