The trouble with outboards

[RAD]

Help! I tried to use the 4 hp Evinrude with the dink early in the season B-4 the stinking rain and the only way it'll stay running is with a little or a lot of choke, hmm... lets clean out the carb and see what happens, same problem sooo I see an ad on Craig's list for a 4 hp Merc and its in mint condition and cheap so I say screw the Evinrude I'll fix it later and proceed to set up the Mercury on the dink
Set the choke,open the fuel valve, pull the cord and varoom! cough shut off,pull the cord and varoom! cough shut off,pull the cord and varoom! cough and now I give it a little choke and it likes that but then it shut off
OK now I got two 4 hp engines doing the exact same thing now tomorrow morning I plan on 1-new fuel,2-pull the carb and put it on the operating table with a can of carb cleaner,3-reassemble and hope this solves the problem
(I thought that with the Evinrude)
any advice,am I missing something other than don't use gas with Ethanol cause I suspect this is the root of the problem

 

[Alec]

The first thing I'd check is the main jet in the carb. It doesn't take much of a restriction at all to keep them from running. I never have luck with carb cleaner for removing varnish in the fuel system. Remove the jet & clean it out with something that won't damage the opening, like a nylon bristle from a brush.

 

[tsmwebb]

I'm guessing dirty or wet fuel or fuel tanks has resulted in a partially blocked carbs. Some outboards with integral gravity feed tanks don't even have a screen to filter out the rocks and stuff from the fuel. Once the tanks get a bit of contamination in them you'll have ongoing carb issues until you clean the tanks.

--Tom.

 

[RAD]

actually both fuel pumps have screens built into them but I'm thinking that the carb cleaner might not be enough and there's a restriction in the main jet, when I dropped the float bowl on the Evinrude it was spotless

 

[Ray T]

I have a 4hp Nissan with an integral tank. the first year I had it I was continually getting water in the carb. I had to take a screwdriver with me to drain the carb when needed. I finally figured I was getting condensation from the heating and cooling of the fuel tank. My solution was to get a 3 gal external tank which solved the problem.

 

[Stu Jackson]

Outboards

Some other ideas besides the usual "it's the carb" answer:

Our kill switch connection was faulty. If that's the case, it only started after 60 pulls. NOT fun!

Check the spark plugs and the spark.

Enjoy rowing????

 

[caguy]

How this for frustration, we went down to the marina for the first time in 1 1/2 months. The Motor would not idle except with the choke full on. Of course I found this out after putting the boat in the water. Cancelled the day reloaded and stored the boat. Pulled the 86# motor off (seems heavier than last year) and struggled it into the back of the truck to take it home. Now the sun is out and the wife says she really wanted to go sailing. I got the motor home and put in a trash can of water and it started on the first pull. It ran perfectly. I let I run for 20 mins and tried again and again it fired up first pull. Tried it again this morning and things look great. Hopefully all will go well today. Last year when I had difficulty with it I took it to a shop where he cleaned the carb in a ultrasound machine for 1 hour. He replaced one jet and carb plug reassemble and tuned and it ran well all last year.

 

[guest]

Outboard

Silly question, but is the fuel feed valve on? I have a five horse two cycle Merc with integral tank. It always starts and runs like a champ. It does have a fuel flow valve on the port side of the engine to select external or internal tank source or fuel flow off.

Terry Cox

 

[MrBee]

You did say BOTH motors acted the same.... that would lead me to FIRST check the Fuel tank.
Don't do anything to the motors till you dump the tank, clean it a little, take MOTOR end off the fuel hose and make sure new fuel comes out then put the fitting back on. NOW hook to motor and let run for a while, till the new fuel makes it into and past the carb.

Both motors, same problem, no need to mess with carbs just need clean fuel to work it's way though system.

Bee

Just realized it's a 4 hp, if they both have the integral tank, did you put fuel in both tanks from the same source ?

 

[RAD]

OK
Here's where I'm at:
got up early and took the carb off the Merc (5 min job) and took it all apart, found what looked like a hair ball between the fuel pump and the carb inlet screen,I suspect it might have been the remains of a spiders web that went through the fuel system,
also took the bowl apart and gave every thing a Gumout bath and after I put it together I was so confident I filled the tank with fresh fuel and one pull Varoom! :dance:
took a little bit to adjust the carb but this old Mercury is sweet.
Next week I'm going to order a carb rebuild kit for the Evinrude and do the same.
As I was leaving the dock there was a fellow trying to get his small outboard started and was having similar problems and I have figured out that ya gotta have fresh fuel and you cannot leave fuel with Ethanol in it even for a short period of time like a couple of months

 

[caguy]

I had my carb cleaned again and it now runs like a champ. I asked the mechanic about disconnecting the gas line and letting the carb run dry. I understood that it was a good idea for 2 cycle motors. He said that it was a better idea for 4 cycles because the jets are much smaller and become gummed up much faster. I did it this weekend and was amazed at how long the engine ran on what was in the bowl. I even revved it up a bit to rush the process. I ran for a good three to four minutes.
Just thought I would share this information with you.
Frank

 

[blue noser]

hey there frank, working the nites on the east coast canada here, winch all done and boat in water thanks for help, speaking of motors mine came with a 15 and is to big looking for a 2 stroke 6 or 9

wade

 

[bffatcat]

finicky outboards

9 out of 10 times its the carb or the fuel. outboard motors dont like ethanol. Use old gas
and your looking for trouble. Never use gas that is more than 30 days old.

 

[shemandr]

Other problems with the Nisson 4's can be leakage of air into the fuel system. I had the same problem (wouldn't run without the choke - stalling). I put in an inline fuel filter and hose clamps instead of those clips. Big improvement. The on/off valve for the fuel leaks too. I haven't replaced it yet but I leave it in the on position where it doesn't leak. I used gas from my 2 cycle snow blower and it was fine. Fresh gas is best but how do you dispose of old? Since these motors are gravity fed the in line filter probably limits the high speed delivery of fuel but I don't run the engine fast that often. I would much rather have it start on one or two pulls which is the case now.

 

[sailingdog]

Do you have a RACOR type fuel/water separator filter in the fuel line. If not, adding one is probably a really good idea.

 

[Rick D]

Bad Gas & Carb Odyssey

I left fuel in my 3.3 Merc OB for two months. It would not start. Got it to Catalina. Pulled the bowl drain & needle valve and sprayed carb cleaner into it. No good. Pulled off the cowling and carb. Disassembled carb. Cleaned it up. Reassembled. Ran fine... for one day. Next day would only run with part choke. Pulled carb apart. Cleaned it all up. Readjusted float. Put back together. Ran great... for two more days. Then, kept stalling and only ran a short time and only with choke. Paddled upwind and current for 40 minutes to boat. Pulled carb apart for third time. While putting it back on, noticed the fuel tank was empty. Filled up tank. OB runs better than ever. Duh.

Moral is that gas goes bad really fast, especially in summer. Use preservative whenever you store it and drain the carb. Don't buy more gas than you expect to use. Check your gas tank before you overhaul the carb.

 

[Honeyman]

Ethanol in your special California mix would be my guess as to main culprit.

 

[caguy]

Can you buy gas without ethanol in California?

 

[Lee Coller]

Can you buy gas without ethanol in California?

No, but you can in Tijuana. That's what my outboard mechanic recommends (though I haven't actually bothered to do that yet, I just make sure I always use fresh fuel).

 

[kenn]

Gotta respect the outboard

Our Sandpiper 565 came with a '81 or '82 Suzuki 5 HP 2-stroke. This is our third season with it.

It took me a while to learn how to prime and start it without flooding it, so now it starts first or second pull almost always. Once running, it's always been smooth and powerful at mostl speeds.

For us the magic is
- we use the top grade of Shell gas, for the high octane and because (in Canada at least) the top grade contains no ethanol
- we always add fuel stabilizer right away
- we use premium 2-stroke oil
- we don't keep gas over the winter. we buy new gas in the spring.

Our tank has a fine metal screen and the motor has an inline fuel filter.

For service, we replaced the sparkplugs last year, and I inspect and re-gap them every spring. I was intending to remove and clean the carb this year, but the engine started third pull, and it's still running very nice, so I may put the carb service off til the fall or next spring.

We were given a Suzuki O/B service guide with the boat, so that helps. Also, the May 2009 issue of Practical Boat Owner (a UK magazine) had a great pictorial article about disassembling and servicing small 2-stroke outboard carbs.