Challenge: Wake Up The Mechanics - Outboard Challenge

[Ex-Calif]

OK - I just bought a new dink. I don't know much of the history and it won't start. Some of the following is done because it won't start, some is done because it is new to me and i want to baseline the maintenance.

Originally Posted by ssullivan

Spark

1/ Make sure the kill switch is on run

2/ Pull the secondary wire off the spark plug, hold it with a pair of insulated pliers about 3/4 to 1 inch off the spark plug connector. Pull the start cord. There should be a bright fat blue spark that is capable of jumping the gap to the spark plug. If there is no spark you have a magneto problem. If the spark is weak - only will jump a very small gap - replace the secondary (spark plug) cable and repeat. (I would likely replace the plug wire as a matter of course)

3/ Replace the spark plug. Gap it properly. Evaluate removed plug. A light tan dry plug is best although it might end up blackish and carbonated. A very oily plug could indicate ring problems. You can get a set of plug evaluation pictures off the internet.

4/ With the plug still removed and the secondary wire attached pull the start cord. There should be a nice bright blue spark across the gap.

This should confirm a good spark.

The magneto itself is pretty bullet proof. I have had a couple of cases where the engine quits when hot. By the time the magneto is pulled and measured with an ohm meter all is well. I had one breaking down at temperature. If you have an engine that quits but will start up 20 minutes later - suspect the magneto.

Originally Posted by ssullivan

Fuel

You don't really know anything about the fuel system. I would dump the fuel from the tank and flush the tank, clean all the filters including any in the tank, lines engine etc.

The inability to start when cold is likely related to fuel air mixture. The choke restricts the air to create a richer mixture for cold start. However gummy and carbon build up could be causing the carb to not work properly.

Before pulling the carb for a cleaning I would employ Roy's method with carb cleaner. Don't overchoke but after an inital dousing and soak, some starter fluid will help the motor to fire.

Then I would liberally apply the magic cleaning fluid per Roy's method.

With the air filter remove I would also check the choke mechanism to verify that when I move the choke lever the choke plate is doing its business.

Originally Posted by ssullivan

Air

This is probably the easiest part. Remove and clean or replace the air filter and technically the choke is part of the air system.

The engine should start and fire now. If it doesn't the next steps get more complicated including a compression check.

However you can evaluate the compression by slowly puling the start cord. You can feel if it is making compression. If you can feel compression there should be enough to start. If there is low compression you'll notice low power and maybe excessive smoke. You will likely have a wet plug as well.

[Sunspot Baby]

Spark:

Since she almost starts, you probably have spark but it is easy enough to check.

Fuel/Air mixture: Will she start with a little starting fluid sprayed into the carb? If so you have definitely nailed it as a fuel/air problem.

After checking all the simple things it could come down to bad fuel (yes it does go bad) and/or a gummed up carb.

The most frequent problem I have on my 2 stroke is a bad fuel hose. I always carry a new one as a spare.

When you kill the engine to store it for a while, disconnect the fuel hose and let the engine run until she dies. That reduces carburetor gumming.

If it is a gummed up carb, spraying something into the carb will not clean needle and seat problems. Luckily, these little carbs are easy to disassemble, clean, and reassemble. Get a carb kit from your friendly local outboard shop.

George

[donradcliffe]

1. Pull spark plug out--if wet, dry off. If dry, remember this.
2. Drain carburetor bowl, and hopefully the bad fuel and water.
3. Try to start. If no sucess, repeat step 1. If still dry, you are not getting fuel. If wet, you have bad fuel or ignition problem.
4. Squirt starting fluid in carb and try again. If no success, you probably have ignition problems.

Fuel probems:
1. Take carb bowl off, look for dirt and water, and clean out (storing engine with the new enthanol-mix fuels makes this more and more common).
2. Take off and clean float valve, check that the float is dry.
3. Open fuel valve (where tank is on engine top) or use squeeze bulb (external tank) to make sure fuel flows into carb.
4. Try again with new fuel.

Ignition problems
1. Replace plug
2. Pull plug and hold alongside block with rag, then pull starter cord and look for spark
3. Replace coil (I had a Tohatsu 3.5 with weak coil which gave me lots of exercise until I replaced it).

[Therapy]

And the answer is????

[Ragnar]

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.

Try all this first and put just a touch of rubbing alcohol (like a couple capfulls ) in your gas maybe a capful of auto trans fluid.
the alcohol hydrolyzes with the water and will clean out you tank while the lubricating and detergent properties of the trany fluid will help clean out the jets and carb. this is of course after you have it running by doing the above steps
I have dome this on autos for years with great success and also the 350 in my chris craft. I can not vouch for the 2 stroke motor application the last 2 stroke I owned was when I was 8 i got a broken down minibike and a crashed honda hr75 put the motor into the minibike frame and had a death trap.
after that my dad banned me from tinkering with small motors.

[Ex-Calif]

Originally Posted by Therapy

And the answer is????

Sully, had the main areas to look at first.

Roy had a good troubleshooting methodology and donradcliffe, although a little late to the party had a nice concise list of things to check.

The example was hypothetical.

The key is to be organized and thorough in your troubleshooting.

I chased a coil problem in my Jeep Cherokee for about 6 weeks and about $900 bucks. I changed the coil first along with spark plug wires, plugs etc. The thing would run a day and then quit when hot. Cool it off and it would start again. I eventually changed the main computer with an aftermarket one for about $600. Same problem.

I went back and started again. The second time I changed the coil it solved. The new coil I bought was bad from the factory and would generate an open in the primary winding when hot - sometimes. I found it by carrying my meter around and checking it when the thing quit and before it cooled off.

[spencer53]

SEAFOAM! The stuff works great. Oil / gas mix sitting in the carb bowl for long periods is not a good thing. Mix some seafoam with the gas when you get her going.

[Therapy]

Originally Posted by Ex-Calif

Sully, had the main areas to look at first.

OOPS!


I got mixed up on threads.

Sully has a Honda idle problem and he never posted the answer.

[perchance]

If you haven't maxed out your credit card deep six it and a buy a new one .Just kidding. A trick i have used on small engines is to inject some fuel into the spark plug hole to get it to run.Some times this is enough to clear those tiny little particles out of the jets. If it starts and then quits clean your fuel system from end to end and check for vacuum leaks.

[Newport17]

If you aren't getting fuel check the pickup tube in the tank, sometimes they crack and suck air.

[sandy daugherty]

The night before, set up a little candle-lit alter, burn incense and douse in a thimble full of chicken blood. Develop a firm mental picture of the motor leaping into life at the mere snap of your fingers, loyal as a labrador retriever, ready to run all day and ask for more.

On the morning of the start, probe the bottom of the tank with a basting bulb and examine its contents in a clear glass container after swirling towards the rising sun with an appropriate incatation. If a clear fluid collects at the bottom, or a film of flotsum appears, buy a new tank, hose, connectors and fresh gasoline, add the exact amount of name brand oil using calibrated scales and the most precise measurement possible, after getting a jury of eight to agree on the proportions. Drain all fuel from the engine, blowing out with filtered compressed air. Wash and dry the starter rope. Remove the spark plug, confirm the proper gap, and analyze any vapors that emerge while cranking the unplugged engine 50 times, repeating "My engine loves me more than life itself." Before connecting the tank and hose, compress the little silver ball in the end and pump two ounces of fuel/oil mix onto a clean cotton handkerchief. allow the fuel to evaporate and confirm that five drops of oil remain, by weight. Check for 3 mm of spark from the plug lead to the cylinder head, lubricate and inset plug, attach plug lead. Choke full (or plug intake if there is no choke, squeeze bulb firmly, completely, and slowly three times. Image the motor motoring smoothly, contentedly, happily thru clear water on a balmy day, with a bevy of bikini beauties bathing its virile bonnet with admiring and grateful glances, then shout "For God, glory, and eternal good ratings, Start!" and pull the starter rope with the strength of ten, the conviction of the saints, the assurance of the everafter, and hear, in your own mind, the adulation of the surrounding crowd, eclipsed only by the mighty roar of the engine as it fulfills its destiny in life!!!!!


repeat.

[dolcesails]

all good advice the spark plug might be gas fouled it will still show a spark, the spark needs to be blue if it is not change the plug

[twisty]

I actually had this exact problem last summer but it was a 1992 50 Johnson spl. Ran fine on the ears in the guys driveway, stopped on the way home got another tank of gas for it and it never ran again(until I fixed it).

1. Plugs, looked good for sitting for 3 years
2. Spark, Ouch yep It's got spark.

Think... Whats changed in the drive from there to here...
GAS!

New gas has ethanol, old gas doesn't(we could still get gas without ethanol until July of this year). Ethanol makes all the gunk move.

1. SeaFoam Helped but still won't idle
2. Clean carbs, Much better but still not idling the way I would like it to.
3 Clean Carbs replce needle and seat(should have not been lazy and done it the first) time runs AWESOME, let's go fishing, oh wait I have t put a new teleflex in it first. DAMN!

The point is before you go 'fishing' for a problem figure out what has changed since it last ran.

[waterworldly]

I bought an 18 year old Yamaha 15. Took it into a very reliable outboard service outlet for a 100 hour tuneup. Has never given me a problem since with just regular maintenance. Spend the money once and enjoy the rest of your weekends for the season.

[haurakiinc]

may have spark but coud be weak clean rust of fly wheel to coil pickups spray with crc make sure gap from coil to fly wheel is right cig paper is good gap if this is faulty will run fine when hot but hard to start good trick to over come weak spark is to pull ht cap and to sit on lose to make bad contact on spark plug will make condser work harder