Wit's end with my outboard

[DougMc]

I had the exact same motor with a very similar problem. I assumed, of course, carb and did absolutely everything.
Because it would fire quite easily, I assumed the spark was fine. But, the plug was the problem.

A new spark plug cured everything, and my multiple carb cleanings, rebuild kit, etc turned out not to do the trick. It starts first pull, and keeps on running.
doug

[CaptMike02]

I had a similar issue with my new one... I RTFM (read the f__n manual) and found out there is a fuel release on the back end of the carb, round the bowl. if you open that till gas comes out it will fill the bowl back up and you'll be good as new. If you tilt the engine apparently you have to go through that procedure again...

[jimellifritt]

Originally Posted by JebLostInSpace

Trying to get my dang outboard to run. Why is it these buggers are always so finicky????

I have a 6 HP Tohatsu 4-stroke outboard. I bought it new last year. It sat unused, out of the water, without fuel in it for ~6 months before I tried getting it going today.

Put some fuel in, choked, set throttle, attached the kill cord, opened the fuel valve. Pulled the cord twice and it started right up. Amazing! Easier than expected after sitting so long. I left it idling and went below to fetch some things while it warmed up. About 3 minutes later, I heard it die.

Now it won't restart. Applying different amounts of choke, fiddling with the throttle position, I can't get it to even cough. The cord pulls, it turns over, but no ignition. I suspect it's not getting fuel. Maybe it ran initially on some residual fuel that is now gone, and it's not getting any of the new fuel I put in the tank.

I check over all the fuel lines for kinks. Other than that, there's not much I can see to do. No hidden fuel shut-off valve that I can find. I'm using the internal tank and it doesn't have a primer bulb that I can find.

After a few dozen pulls on the cord, I have a new theory. Maybe I flooded it with too much fuel? So I shut off the fuel valve and give it 10 good pulls in hopes of draining excess fuel. Flip the fuel valve back open, give it half choke and pull the cord.

It coughs! That must have been the problem! But it won't actually run yet. I fiddle with the choke and throttle settings some more trying to find a combo that will make it happy. It coughs 4 or 5 more times, and then nothing again.

Well ****, maybe I flooded it again. Shut the fuel off, give it ten pulls, open the fuel valve, try again. Nothing. Repeat, repeat, repeat. Nothing. No more coughing.

I check the oil. Looks a little low so I top it up. Try the fuel shutoff - pull 10 times - fuel on maneuver a couple more times. Nothing.

I give up and ask the forum. What am I missing here? Why would it behave this way? And why hasn't anyone figured out how to make these bastards start reliably? I've never worked with a small 2 or 4 stroke engine that wasn't an absolute pain in the ass.

same motor as you. mine came back from shop and did not run well. ended up ordering new fuel pump and carb. 2 bolts each. replace and it is now one pull start. needless to say I am now carrying spare carb and fuel pump on our journeys in Mexico and beyond

[Kolchac]

if you did not use it, try to clean the carb. One of those:
https://vevor.ca/products/new-stainl...4aAvF0EALw_wcB

[merrydolphin]

Next chance you get buy a 2 stroke. If in the us. A used 2 stroke will be more dependable than a new 4 stroke. Also so much lighter.

[mattiejo]

If it is an old fuel/carb issue try ‘Mechanic in a Bottle’ it’s allowed me to start several small engines before

[hgd137]

I solved my new Tohatzu 9.8hp starting problem by junking it and buying a epropulsion electric outboard motor!!! This sounds like the exact nightmare I went through!!!!

[davitosan]

The problem you have could be as simple as not having opened the air inlet on the fuel tank

[davitosan]

Make sure that the air inlet on the tank is open

[conchaway]

See if a mud dauber has clogged the water outlet hole.

[lituya1617]

As a mechanic, this seems an easy problem. Do your troubleshooting very systematically or you will miss something. 90% of no starts in a long-idle engine are fuel related. You already have some useful information. Build on that. I assume you have clean fuel in a clean tank. Follow these steps:
1. Take off the fuel line at the carb and make sure fuel flows freely to the carb.
2. Spray a little starting fluid in the intake.
3. Make sure the ignition is turned on.
4. Pull the starter handle. If it runs, you are in business. Run it as hard as you can for a few minutes to clean out any gunk in the carb, loosen stuck valves, etc.
5. If still no start, take out the spark plug and check for spark. Make sure the spark plug is clean and in good condition. You should get a bright blue spark with normal cranking. If not, you have to check the ignition circuit and coil. 95% of all electrical problems boil down to a bad connection - check the connections. Since it ran once, it is probably in time and the spark is fine. If you have a good spark, move on. Just assume the timing is OK since it is fixed by the flywheel (though sometimes a flywheel can sheer off the key and bugger up the timing, that is very rare).
6. Put a finger in the spark plug hole and see if pulling the starter handle produces good pressure. If not, you have an internal engine problem but I would bet you have good compression. If so, move on.
7. If spark and compression are good, make sure there is no obstruction to the air inlet. Sometimes animals live in there. If not obstructed, move on.
8. Since compression, air, gasoline, and spark are OK, you are left with a fuel delivery problem; i.e., the carb is the problem.
9. You have two options: a new carb (my choice) or clean the carb you have. Both approaches work fine but it is a lot faster to just put on a new carb. These little carbs are prone to gum up, corrode, and get plugged by tiny pieces of crap. If you clean it, don't expect to actually see what the problem was since the smallest piece of junk will stop these little engines. Do your carb cleaning work over a piece of white paper so you don't lose parts, some are tiny. Springs in there will fly so be careful - they can be very hard to find in an unclean work space.
10. When you put on the new carb, use a little starting fluid to get started and avoid a lot of cranking. In the future, use non-ethanol gasoline in your engine. I don't care what the manufacturers say, ethanol will corrode an aluminum carburetor, eat up fuel lines, and cause rapid breakdown and gum depositing in the system. Run your engine completely dry of gasoline if you do not intend to use it in 30 days. Stabil will extend that to six months but it is easier just to empty the system. I usually put a little 50:1 mixed gas in the tank when I run it dry to oil up the inside of the carb and the tank to prevent corrosion. Good luck. If you are systematic, all engines are easy to diagnose. Compression, spark, timing, fuel = it runs. Of course, all these have to be in the correct amounts, of the appropriate type, and at the right time.

[surfmachine]

Mate. It’s the two mild steel screws that hold the fuel float or something in the fuel bowl. They rust and block up the idle and main jets. Swap them out for stainless steel bolts and no more problems. I have had 2 9.8 hp tohatsus and same problem. Amazing difference 2 bolts will make.
Keith.

[lituya1617]

There are a lot of good, motor specific, suggestions on this thread. Of note are the suggestions to open the vent, check water flow for cooling, reprime the carb via the special lever somewhat hidden behind it, replace the fuel pump, replace rusting bolts inside the carburetor bowl, and others. But do the basics first.

[Lodesman]

Originally Posted by JebLostInSpace

Another weird observation: When I pulled the carb today, and started disassembling it, the bowl was full of fuel. (I'm an idiot and forgot again to drain the bowl first and check for water). I figured that meant I must be getting fuel to the carb, which would narrow down where to look for problems. But when I put everything back together again, it gave me the same second or so of running on the first pull, followed by nothing. I then gave it about 20 more pulls. I could see fuel in the little filter thingy. Then I thought I would drain the bowl on the carb to check for water like I meant to in the beginning. But the bowl was empty...

C'mon, you got this. Say it with me - float valve.

If cleaning the carb, it doesn't pay to cut any corners. Clean everything. Cause that gunk you leave behind above the float valve, just comes downstream and plugs the jets too.

You'll get there.

[Great Dane]

Nobody has mentioned water in the fuel yet. That has been my problem a couple of times.