yamaha outboart

sailaway78 · Jul 1, 2010

Rebuild the carb.

Just go ahead and rebuild the carb, and get it over with. You have a jet partially plugged up. Then, EVERY time you use it, unplug the fuel line and run the carb. dry. Buy fuel in small quantities and put sta-bil in it. Do not use gas the is very old. Much over a month is pressing your luck, although with sta-bil it will last longer. Put a good quality fuel filter in the line. This should have you running problem free for a long time.

Alan · Jul 2, 2010

Fuel system cleaners can break down gum and varnish in the carb. If the problem is dirt these cleaners will be of no help. Take the carb apart and clean it thoroughly. Pay particular attention to the small jet. Blow out the fuel line and clean the tank. As Nice N Easy says an in-line fuel filter is a good idea for prevention.

jibes138 · Jul 2, 2010

I've always used gumout carburetor cleaner to clean the parts when I disassemble the carb. Not sure if it is OK to run it through a two stroke during operation. I've certainly sprayed it in the carburetor throats of my old cars when they had carburetors. But the jets and stuff really need to be removed, soaked and then reassembled and properly adjusted for the right mixture. I just rebuilt the carb on my Johnson 4 HP two stroke and it wouldn't start before the rebuild. Afterward it starts right up and idles fine, same old ten year old spark plugs. Considering how little time is on these small engines I've never found the spark plugs to be the problem. Is it cheap insurance to change them, sure, but if they work fine why bother. If your plugs aren't making a good spark it is probably a supply voltage problem versus the actual plug. I do agree they should be cleaned and gapped though if needed.

Charisma · Jul 2, 2010

Just recently had trouble with my Merc OB, ended up using "seafoam" at the recommendation from someone on this site. Cleaned everything up and my OB now runs and idles fine, also it says you can use it as a stabilizer. Good stuff totally recommend it. Chris

ozarkray · Jul 2, 2010

Try, Try again.

I have not found anything yet to dissolve the gunk that get into the carb. I have a six horse Evenrude that quit working on me this spring. From the texture and color of the gunk, I would think it was a small piece of paper fuel filter that broke loose and got shredded in the float bowl. No sooner would I get it cleaned and running than it would plug up again. Took me three tries at cleaning the carb before I got all the jets and vents clean enough to get it to run properly. So, keep trying, you'll get there.

Ray

Jerry Clark H356 SV Persi · Jul 3, 2010

Go ahead and rebuild

I used three cleaners, runing and not running, trying to fix the same problem two seasons ago in a Yamaha 4HP, 4 stroke. The jets are so small, nothing works to unclog them. The problem is the fuel. In my case, I ran the engine out of fuel in the fall, but that was not enough. I now use stabil and use the engine as often as possible.

tomgrigsby · Jul 3, 2010

With the new ethanol fuels, the alcohol absorbs water. Little critters like the water and grow. Critter byproducts don't dissolve with gumout etc. You have to clean out the little holes. Guitar strings (.010) or other small wire, compressed air etc. and you can do it. As noted earlier, after every use, unplug the fuel line and let the motor run out of gas. Even pull the choke as it starts to sputter and get that last little bit out of the carb. I did that for 10 years with an evinrude 5hp fisherman. Sometimes let it sit for 6 months or more. Always started right up and ran fine.

Douglast · Jul 3, 2010

you don't need a rebuild if it has been recently done...just need to take that float bowl off and get the main and pilot jets...etc clean..just be careful not to get your float setting out of wack..be careful and you will be ok..