General 2-Stroke Help

[lukereneeseth]

Just purchased my 1st outboard and after some quick general advice as it seems pretty debateable across the spectrum of boat owners.

As deciphered from the sticker it is:
Hong Kong, Johnson, 25HP, Rope Start Australia, 1996. (2 stroke)

Just wanting to know:
50:1 or 75:1 mix of standard OEM oil or Synthetic Oil?
Do you take the fuel hose off while flushing and wait for it to start spluttering (fuel out of system) then shut down the motor?
How often would you recommend services on a 17 year old motor relating to hours?

Thanks

[matt jorg]

Mate I'd be looking it up on the net but if no info is available I'd suggest running the heavier mix 50.1 as some extra lube will prevent it going bang.
I wouldn't run it dry between use the rings will grab the bore and shows over!
Don't expect it to idle perfect or troll at slow speed it'll oil up.

I've had experience with 2 stroke engines and motorbikes and that's the way I'd be inclined.
Cheers matt

[morgo_racing]

+1 on the above... if you are going to run it at full throttle or close for any length of time, you'll need to run it at 50:1, or you could go a bit higher with a full synthetic oil. Also, I'd be leaving a bit of fuel in the motor after you shut it off, and just using an additive like stabil or something to stop the fuel going off.. Cheers

Russ

[lukereneeseth]

thanks. yeah did a fair bit of searching on the topic and everyone seemed to have a different point of view from 50:1 75:1 100:1.
Full throttle yes, trolling no. Will get an electric down the track for that, tend to get a fair hit of current in the Maroochy river.

[Flyman1]

I have previously owned a 25hp Johnno. Good motor but run it at 50:1 mix. I tried all the two stroke oils like Castrol etc from Supercheap. The best I found and gave me less smoke was Yammalube. When flushing don't run it dry as no fuel in the carby etc dries the gaskets out, cuasing leaks later. The fuel stops them from drying out especially if the boat is stored for a month or two.

[CK]

I had this motor from new. It was my first brand new motor & served me well for over 10 years. Not the smoothest beast but reliable when it finally got going. More on that below.
Ran it on 50:1 and various oils. Never tried the yamalube in it, but Castrol, nautilus, and various others all had a run in her.

My only complaint with it was its hard starting on cold winters mornings. It would take countless pulls of the rope to fire the girl up. Once started it was good all day, usually starting on the first pull. I could never figure out why it was such a pig first thing and a few I have seen after seem to suffer the same trouble. Be interested if yours is similar & what if anything you have found to fix it.

I used to run the carby dry and never had an issue, but then I used the boat regularly, so perhaps the running dry was pretty pointless. Only time it ever failed me was a split fuel line from the choke, meaning I couldn't prime it & after a long hiatus. Months, maybe close to a year, went by between uses and despite a fairly ridged washdown routine, I had a thermostat seize up resulting in a tow back, but no damage to the motor.

A word of advice. Don't do as one supposed outboard mechanic advised and remove the thermostat. To do so will mean the motor never reaches a good operating temperature. This results in it running rich & fouling plugs.

If you plan on doing your own maintenance, perhaps a routine check of the thermostat is a wise thing, particularly as its easy to get too and the gaskets are (were) cheap!

[sexton]

Originally Posted by Flyman1

When flushing don't run it dry as no fuel in the carby etc dries the gaskets out, cuasing leaks later. The fuel stops them from drying out especially if the boat is stored for a month or two.

I have always flushed mine out till its dry...But just before xmas last year in my first couple of days into the chrissy holidays I did a gasket resulting in the boat being off the water for about 2 months...
The boat mechanic said the gasket was cracked and leaking, but never told me what had caused it to do so in the first place.

Maybe that's what had caused the problem by running it dry

Hmm I think I might start leaving a little bit of fuel in there for now on...

[lukereneeseth]

thanks heaps for the advice fellas. Was thinking of just going the DohDohDoh Quicksilver oil or Caltex's blend (Caltex seems to originate from BP Kwinana, in turn made for Yama and merc = decent enough).

I figure its an old motor built back in the dying days of machinery being made to last so with oils/ quality progressing over the last 17 years im sure all of the oils would be fit to do what they're made for in this outboard.