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wrote:

I was given a small aluminum runabout last fall. It has a 33hp
Evinrude "SkiTwin" engine. I put it in the water and it fired
right up. Perfect little boat for a small lake and tubing for a
10yr old. I've been guessing on the fuel

il mix as I haven't
been able to find any docs or info. Just informal and conflicting
advice ranging from 24:1 to 50:1. I've been running it on appx
40:1 and its been happy. I've put about 3 hrs total on it from
then till now, 2.8 of them last fall.

A few days ago I fired it up for the season and it ran great. Ran it
for about 20mins at all speeds. Tank was low so I pulled it and
refilled it. I found a bit of info on the web that said 32:1 , so
since
it was the 1st time I found something that sounded firm, I mixed
up a fresh tank of 32:1 and plugged it in. Started and stalled,
Started
and Stalled. No start after that. The next day I realized I had left
the
vent on the tank closed, and opened it expecting ignition. No
joy. Still no start.

So, I pulled the cowl, and checked the plugs, they're a bit dirty
but not fouled or worn. I pulled the fuel line at the engine and
confirmed that gas is coming thru the line by pushing the ball
valve in and squeezing the bulb. I see fuel/oil in the water when
trying to start.

I know car engines and am a careful DIY mechanic. It behaves
like theres no spark, but that doesn't jive with changing fuel.
I expected fouled plugs due to a possibly wrong fuel mix for
this motor, but found them to be OK.

So there's the whole puzzle. My questions a
- My next step will be to verify a spark on the plug. Can I pull
the plug, attach the wire, ground it on the block to test

Yes - do it in a well vented area. The OMC spark tester just clamps to
the block.

or is
that a No No on this motor?
- Does ANYONE know what fuel

il mix i should be feeding it?

The 33's & 28's always did fine for us in fleet use(we had several still
going strong 20 years ago) with TCW-3 oil at 50:1 (a pint to a six
gallon tank).

I read 32:1 and was also told that 50:1 is Ok with modern day
2cycle oil.

Sounds good.

- should I pull the hose from the output side of the fuel pump
looking thing and verify flow, or does the slick when trying to
start already confirm flow?

The engine is flooded. Too much fuel. Clean & dry the plugs, don't use
the choke, crack the throttle open a little extra to help start a
flooded engine.

- Based on the events as described, any ideas? I'm starting to
think it may be an unrelated failure of some sort, but as I stated,
I'm completely new to 2cycle engines.

Any advice other than pull the engine and hump it off to a shop
is requested. I'll hump it off as a last resort, but would rather
figure it out with the help of some good advice.

Basics first - fuel - air - compression - spark. If you're using
Champion spark plugs, change them annually - J4C plugs.

Heres the patient:
http://geocities.com/mpdsville1/MyBoat/

Looks great!

Rob