2 stroke oil

[brinky]

Hi,
I was wondering what a 2 stoke engine does if the auto oil mixing stops working.Will the engine stop, or smoke? I know some people prefer manual mixing.
Thanks

[Searider]

If it stops pumping oil I guess your engine will seize up

[m chappelow]

depends how fast you are going ,,usually squeels /chirps / overheats /rattles then either power drops off gradual or suddenly stops dead .

[9D280]

You won't get much life out your powerhead if that happens!

Any "auto mixing" system I've seen has an oil flow sensor between pump and block. I guess it depends how paranoid you are about it failing. Merc had a transom mount system back in the late 70s / early 80s that was notoriously unreliable, but I believe a proportion of the problems were down to the owners not changing the battery......


If you are uneasy about it and want to run premix remember you'll need to either physically disconnect the oil pump (or it will sieze!) and also disable all the alarm circuits, the other option is to connect the oil supply hose back to the tank to confuse the engine into thinking it's still pumping oil. Remember to block the oil in port(s) to the block as well or you'll ingest air in the wrong places.....

Having used both I'd say premix is OK if you are running open throttle a lot of the time and don't mind guddling and getting messy at every fill. Other down side to premix is if you get a fuel spill, your deck turns into a skating rink when the petrol evaporates.......

[brinky]

There is an alarm for the oil, is there a way of testing it?
I can't imagine I would here it over the engine noise...
If there seems to be more smoke coming from the exaust, is this a sign of too much oil and if so is this harmful ????
As you can probably tell I don't know much about these things and am just trying to avoid any costly problems.

[Locozodiac]

Originally Posted by brinky

If there seems to be more smoke coming from the exaust, is this a sign of too much oil and if so is this harmful ????

When oil pump stops working, will ruin your engine block, specially at wot. When you turn engine on from cold, will see dense smoke for a short while, when gets to working temperarure slight les, but still will see and smell it, assume auto lube systems delivers less oil at idle speeds and more oil when at wot. Somebody here for sure knows.

Happy Boating

[yorfuoj]

To avoid an engine seizure in case of automix failure, I would recommend to add 0.5% of oil into the gasoline.
If the automix is ok, this will add a few oil to the right %age, not a problem.
If for any reason it fails, this will protect the engine against a dramatic seizure, it will start to seize slowly with a characteristic metallic sound and a loss of power - then it could recover.

A friend had a 50 Tohatsu, and he had the bad idea to open the oil filter to clean it. But the oil tank level was lower than the filter one, so the automix pump pumped air instead of oil.
He complained that the motor was regularly emitting a special noise before stopping dead every 2 or 3 minutes, then restarted immediately with the key - this happened during several days ...
I found the oil tube completely dry, I added oil into the tank, bleeded the air, added 10% of oil into the gasoline and run it for one hour.
Still alive now, 4 years later ! Good Tohatsu ...

[Jizm]

Originally Posted by yorfuoj

A friend had a 50 Tohatsu, and he had the bad idea to open the oil filter to clean it. But the oil tank level was lower than the filter one, so the automix pump pumped air instead of oil.
He complained that the motor was regularly emitting a special noise before stopping dead every 2 or 3 minutes, then restarted immediately with the key - this happened during several days ...
I found the oil tube completely dry, I added oil into the tank, bleeded the air, added 10% of oil into the gasoline and run it for one hour.
Still alive now, 4 years later ! Good Tohatsu ...

Good advert for them...