Challenge: Wake Up The Mechanics - Outboard Challenge

[Ex-Calif]

You've recently bought a used dink at a great price. It has a small 5.5hp 2 stroke outboard engine on it with a separate plastic fuel tank with associated black fuel hose, squeeze bulb etc. that plugs into a quick release on the front of the motor. It could be a yammie or tohatsu. It's your basic 2 stroke engine with fuel filters, magnetos, spark plug etc.

The previous owner claims it is 8 years old and has only been driven on Sundays by a little old lady in the slow lane going to church. In other words he claims low hours. He also claims that it runs great but, "once in a while she's stubborn and ya gotta choke 'er. I also had 'er serviced by Bob the mechanic 6 months ago." you putter around the bay for 30 minutes and decide that the price is fair so you make the deal.

You load her up on the trailer that Sunday and drive 500 miles north back home where she sits on the trailer until next Saturday when you splash her.

You choke her, and squeeze her fuel bulb, you pull the cord until your arm is about to come off but she won't start. You get an almost start sometimes but she won't catch. You remember that when you started her yourself last weekend the engine cover was already warm. You also remember blue smoke but can't recall if it was excesive or just normal like other dinks you've driven. It's also a little colder 500 miles north.

OK mechanics and wanna bees.

What are the logical and complete troubleshooting steps?

[ssullivan]

Originally Posted by Ex-Calif

What are the logical and complete troubleshooting steps?

Spark

Fuel

Air

(Electronics)

Those are the steps!

Pull the plug and (carefully) see if you see a spark.
If so,

Go through the entire fuel system - tank to intake manifold. Start with fuel you know is good, check primer bulb, connections, hose, fuel pump, carb (adjust if necessary). This includes choke and throttle mechanisms. See that fuel is getting to the engine in the right quantity.

[psteele235]

You load her up on the trailer the next Sunday and drive 500 miles south where you splash him!

[Wotname]

Along the same lines of Sully.
Assuming the compression felt OK when you did the deal (otherwise why do the deal ) then toss the spark plug over the side (unless this contravenes any MARPOL regulations ).
Before fitting the new one, check not only for spark but also that the spark is strong (good, hot, bright or whatever words you like).
If so, pull the motor through several time with plug removed and see (carefully) what air/fuel mixture comes out. Don't have the plug connected and just hanging nearby on its HT cable at this stage and don't ask why I know this!!!!

Anyway this should narrow down the fault to compression, ignition or fuel.

[Zach]

I make sure the kill switch is set to run, and all seats and tables are locked in their upright position.

[CharlieCobra]

Make sure the kill lanyard is in place.
Make sure the fuel cutoff is open.
Make sure the cap vent is open.
Make sure ya have gas in the tank.
If it still doesn't start, check the spark plug for spark and fouling.
If ya have fuel and a good spark, throttle it down and close the choke.
If that doesn't work, let it sit because ya flooded it or pull the carb bowl and empty it, checking for water in the bottom first.

[Zephyr's Aura]

Make sure your gas is mixed properly. If it has seperated or wasn't mix well to begin with you might be gumming it up with to much oil.

Just my 2 cents worth.

[S/V Antares]

Checthe kill switch. Then take the spark plug out and with the plug wire in place hold the plug body against the head and pull the starter cord. If the plug sparks put it back together and go to the carb. Fuel does not last like it used to.

[David M]

Start with the basics first. If you kept pulling the pull start after you got a sputter then you flooded the engine. Put the choke back in.

[Therapy]

Originally Posted by David M

Start with the basics first. If you kept pulling the pull start after you got a sputter then you flooded the engine. Put the choke back in.

ditto.......

[Chief Engineer]

ditto and change the plug before you put the plug in give it a few pulls to get any sloppy fuel outta the cylinder.

[Roy M]

This was the FIRST Lesson we learned in Outboard Motor Repair: 1. Change the plug. 2. Place the motor in a water tank or in the water. 3. Remove the cowling. 4. Spray Quicksilver Power Tune into the carburetor. 5. Wait 15 minutes, then attempt to start. 6. When the engine catches, spray most of the can into the carburetor, SLOWLY, and stay clear of the big cloud of smoke. 7. When the motor is running with less smoke, empty the remainder of the can into the carb to stall it. 8. Fire the motor up fifteen minutes after the stall. Stay clear of the dense smoke. 9. Start the engine, enjoy the dramatic change. 10. Repeat, once a season.

It's the dirty little secret of outboard repair. It cleans the crap out and the motor sounds like a sewing machine, again. Then, don't tell anyone and collect lots of loot from frustrated boaters.

[Ex-Calif]

Great inputs so far. Some of the troubleshooting might be a little "shotgun" style.

Sully seems to have nailed the major categories. Anyone wanna take a deep dive on how to troubleshoot the igniiton system?

I love RoyM's tip for induction system cleaning and for everyone that said kill switch / lanyard- good one! It's always important to get the obvious.

As for PSteeles solution - I forgot to mention your SUV gets 10 mpg. (1000 / 10) X $4.00 = ouch...

[Wotname]

Originally Posted by Ex-Calif

... Anyone wanna take a deep dive on how to troubleshoot the igniiton system?

I love RoyM's tip for induction system cleaning and for everyone that said kill switch / lanyard- good one! It's always important to get the obvious.

.....

Err... start with the kill switch...

[Therapy]

Originally Posted by Roy M

This was the FIRST Lesson we learned in Outboard Motor Repair: 1. Change the plug. 2. Place the motor in a water tank or in the water. 3. Remove the cowling. 4. Spray Quicksilver Power Tune into the carburetor. 5. Wait 15 minutes, then attempt to start. 6. When the engine catches, spray most of the can into the carburetor, SLOWLY, and stay clear of the big cloud of smoke. 7. When the motor is running with less smoke, empty the remainder of the can into the carb to stall it. 8. Fire the motor up fifteen minutes after the stall. Stay clear of the dense smoke. 9. Start the engine, enjoy the dramatic change. 10. Repeat, once a season.

It's the dirty little secret of outboard repair. It cleans the crap out and the motor sounds like a sewing machine, again. Then, don't tell anyone and collect lots of loot from frustrated boaters.

In my area the same thing is sold.
It is called Sea Foam. Great at de-carbonizing.

Off topic.
I had a motorcycle and always used the key to turn it off (no duh!) One day it wouldn't start. Tried till the battery was weak. Loaded int a van --> shop. The shop called and said it started right up and did I use the kill switch to turn it off. OOOFFFF! How we learn!!