i have a jetski and a boat with an evinrude 115 hp outboard. can
they both use the same gas/oil mix? someone told me it should be
a pint to six gallons but i would rather mix a pint with 5
gallons because it's easier and to be on the safe side if that's
ok. is a pint to 5 gallons ok for both the jetski and the
evinrude?

thanks!

ted

ted@theted. wrote in message
...
i have a jetski and a boat with an evinrude 115 hp outboard. can
they both use the same gas/oil mix? someone told me it should be
a pint to six gallons but i would rather mix a pint with 5
gallons because it's easier and to be on the safe side if that's
ok. is a pint to 5 gallons ok for both the jetski and the
evinrude?

thanks!

ted



It's always wise to follow manufacturers recommendations. Deviating from
them could be trouble.


Wilbur Hubbard

Ted,
Adding lube oil to gasoline lowers the flash point of the fuel increasing the chance of detonation. Oil in the fuel is necessary
for these type of engines, but NEVER use more than the manufacturer's recommendation. Failure to follow this simple direction
could melt the pistons, the heads and effectively ruin the engine and I have seen this hundreds of times. I know this is counter
intuitive, hence the number of times this failure occurs.
Steve

ted@theted. wrote in message ...
i have a jetski and a boat with an evinrude 115 hp outboard. can
they both use the same gas/oil mix? someone told me it should be
a pint to six gallons but i would rather mix a pint with 5
gallons because it's easier and to be on the safe side if that's
ok. is a pint to 5 gallons ok for both the jetski and the
evinrude?

thanks!

ted

"Steve Lusardi" wrote in message
...
Ted,
Adding lube oil to gasoline lowers the flash point of the fuel increasing
the chance of detonation. Oil in the fuel is necessary for these type of
engines, but NEVER use more than the manufacturer's recommendation.
Failure to follow this simple direction could melt the pistons, the heads
and effectively ruin the engine and I have seen this hundreds of times. I
know this is counter intuitive, hence the number of times this failure
occurs.
Steve


Interesting. The Outboard Shop, the local evinrude/johnson dealer, gave me
the exact opposite recommendation. The question came up with my newer engine
which is designed to run on 100-1 mix. They told me it will run just fine
on the same stuff as my older engine, a 50-1 mix. They also cautioned me
that the least "too-little" mix , such as missing by a bit when filling from
a not-empty supply and having to guess at the right amount, could turn it
into an anchor. Failure to use enough deprives the engine of its
lubrication, and things seize up.

Further, my manuals for both engines show to use double the oil in severe
use conditions. I.e., in the newer one, 50-1, in the older one, 25-1. More
oil, at least as inferred from the manuals, assures that won't happen, even
if you overdo it.

I grant you that quadrupling the oil may have some deletorious effects, but
my common sense tells me that 16% more than specified as ADEQUATE should not
be a problem.

Also, I've never seen oil being more subject to explosion/flash than
gasoline. How does adding oil to fuel make it more volatile?

L8R

Skip

--
Morgan 461 #2
SV Flying Pig KI4MPC
See our galleries at www.justpickone.org/skip/gallery!
Follow us at http://groups.google.com/group/flyingpiglog and/or
http://groups.yahoo.com/group/TheFlyingPigLog

"Believe me, my young friend, there is *nothing*-absolutely nothing-half so
much worth doing as simply messing, messing-about-in-boats; messing about in
boats-or *with* boats.
In or out of 'em, it doesn't matter. Nothing seems really to matter, that's
the charm of it.
Whether you get away, or whether you don't; whether you arrive at your
destination or whether you reach somewhere else, or whether you never get
anywhere at all, you're always busy, and you never do anything in
particular; and when you've done it there's always something else to do, and
you can do it if you like, but you'd much better not."

On Oct 25, 12:02*pm, ted@theted. wrote:
i have a jetski and a boat with an evinrude 115 hp outboard. can
they both use the same gas/oil mix? someone told me it should be
a pint to six gallons but i would rather mix a pint with 5
gallons because it's easier and to be on the safe side if that's
ok. is a pint to 5 gallons ok for both the jetski and the
evinrude?

thanks!

ted

I only have smaller 2 strokes and one jetski. The jetski mixes it's
self with a oil pump to the carbs. But I mix the same ratio for all
my small engines without any problems.

Lots of trimming

Also, I've never seen oil being more subject to explosion/flash than
gasoline. How does adding oil to fuel make it more volatile?

L8R

Skip

There are 2 parameters to consider these are the flash point - the min
temp at which it will ignite with a spark or flame etc.
This is typically -45F for petrol (gasoline) and +143F for diesel.
Hence as a boat fuel, diesel is a lot 'safer' than gasoline.

However there is also the autoignition temperature - this is the min
temp where the fuel will simply ignite without a spark or flame.
For Petrol this is 495F and for diesel 410F a fair bit cooler.

So too much oil could lower the auto ignition temp to a point where
pre-ignition happens - not good for your engine.

However I have no idea how much you need to add to cause this kind of
problem.

ted@theted. wrote in message
...
i have a jetski and a boat with an evinrude 115 hp outboard. can
they both use the same gas/oil mix? someone told me it should be
a pint to six gallons but i would rather mix a pint with 5
gallons because it's easier and to be on the safe side if that's
ok. is a pint to 5 gallons ok for both the jetski and the
evinrude?

thanks!

ted

I follow the manual recommendations.
i also dropped into the Vespa scooter store and bought the little plastic
measuring device.
It's great for a 50:1 mix. Saves guess work when out on the high seas.

You can do a test yourself. Place a drop of gasoline down the barrel of a daisy BB gun and fire it....no effect. Use a drop of oil
and you will hear the detonation when the lube oil detonates. Further, try running a diesel engine on high octane gasoline and see
what doesn't happen. You may be able to move to 50:1 from 100:1.....maybe, but modern two stroke engines use a lot more
compression than the older ones and when using too much oil in the mix, you will melt a piston.
Steve

"Flying Pig" wrote in message ...
"Steve Lusardi" wrote in message ...
Ted,
Adding lube oil to gasoline lowers the flash point of the fuel increasing the chance of detonation. Oil in the fuel is
necessary for these type of engines, but NEVER use more than the manufacturer's recommendation. Failure to follow this simple
direction could melt the pistons, the heads and effectively ruin the engine and I have seen this hundreds of times. I know this
is counter intuitive, hence the number of times this failure occurs.
Steve


Interesting. The Outboard Shop, the local evinrude/johnson dealer, gave me the exact opposite recommendation. The question came
up with my newer engine which is designed to run on 100-1 mix. They told me it will run just fine on the same stuff as my older
engine, a 50-1 mix. They also cautioned me that the least "too-little" mix , such as missing by a bit when filling from a
not-empty supply and having to guess at the right amount, could turn it into an anchor. Failure to use enough deprives the
engine of its lubrication, and things seize up.

Further, my manuals for both engines show to use double the oil in severe use conditions. I.e., in the newer one, 50-1, in the
older one, 25-1. More oil, at least as inferred from the manuals, assures that won't happen, even if you overdo it.

I grant you that quadrupling the oil may have some deletorious effects, but my common sense tells me that 16% more than
specified as ADEQUATE should not be a problem.

Also, I've never seen oil being more subject to explosion/flash than gasoline. How does adding oil to fuel make it more
volatile?

L8R

Skip

--
Morgan 461 #2
SV Flying Pig KI4MPC
See our galleries at www.justpickone.org/skip/gallery!
Follow us at http://groups.google.com/group/flyingpiglog and/or
http://groups.yahoo.com/group/TheFlyingPigLog

"Believe me, my young friend, there is *nothing*-absolutely nothing-half so
much worth doing as simply messing, messing-about-in-boats; messing about in
boats-or *with* boats.
In or out of 'em, it doesn't matter. Nothing seems really to matter, that's
the charm of it.
Whether you get away, or whether you don't; whether you arrive at your
destination or whether you reach somewhere else, or whether you never get
anywhere at all, you're always busy, and you never do anything in
particular; and when you've done it there's always something else to do, and
you can do it if you like, but you'd much better not."

Engine repair shops love customers like you....you keep them in business.
Steve

"jamesgangnc" wrote in message ...
On Oct 25, 12:02 pm, ted@theted. wrote:
i have a jetski and a boat with an evinrude 115 hp outboard. can
they both use the same gas/oil mix? someone told me it should be
a pint to six gallons but i would rather mix a pint with 5
gallons because it's easier and to be on the safe side if that's
ok. is a pint to 5 gallons ok for both the jetski and the
evinrude?

thanks!

ted

I only have smaller 2 strokes and one jetski. The jetski mixes it's
self with a oil pump to the carbs. But I mix the same ratio for all
my small engines without any problems.

On Mon, 25 Oct 2010 11:46:00 -0700 (PDT), jamesgangnc
wrote:

On Oct 25, 12:02*pm, ted@theted. wrote:
i have a jetski and a boat with an evinrude 115 hp outboard. can
they both use the same gas/oil mix? someone told me it should be
a pint to six gallons but i would rather mix a pint with 5
gallons because it's easier and to be on the safe side if that's
ok. is a pint to 5 gallons ok for both the jetski and the
evinrude?

thanks!

ted

I only have smaller 2 strokes and one jetski. The jetski mixes it's
self with a oil pump to the carbs.

the guy who was working on it suggested that i have the pump mix
system removed for a couple of reasons. one was because it was
smoking badly meaning it was mixing too much oil, and the other
was because somewhere in that system it was leaking oil into the
hull. he said it could just as easily mix too little as mix too
much and that would ruin the engine, so i figured after getting
lucky and having a second chance it was best to have the messy
threat removed so it won't ever be an issue again.

But I mix the same ratio for all
my small engines without any problems.

what ratio?