2003 Yahama 115 carb "varnishing"

[Capt Jim]

If I don't start this engine more frequently than every 3 weeks it's back to the shop because the carbs have "varnished". Costs ~$200 for repairs.<br />Have new gas, fuel stabilizer in it. Local shop says because of modern gasoline I have to run it weekly. I think I'm getting jerked. Never had this kind of problem with Mercs or even an old Force.Any ideas? Thanks, Jim<br />PS: This is Florida and it's not even that warm to consider being caused by the heat.

 

[BillP]

Re: 2003 Yahama 115 carb "varnishing"

I say BS to the fuel being bad in 3 weeks...unless it is reacting with the fuel stabilizer? Is it sludge or hard varnish? Maybe the tank or fuel hoses are contaminated. Are you running the carbs dry after use? <br /><br />My carb problems went away when I quit running them dry after every use. My grandpappy who owned and operated a Standard Oil service station for 50 yrs in Florida gave me that advice.

 

[gss036]

Re: 2003 Yahama 115 carb "varnishing"

I think you are getting jerked around. No way will the fuel go bad in 2-3 weeks, maybe not even 2-3 months. Mix some Seafoam with your gas. If you have a small tank, mix a can pf Seafoam w/1 gallon gas and run that through, it will definately clean your carbs and carbon you have.

 

[Capt Jim]

Re: 2003 Yahama 115 carb "varnishing"

as far as running the engine dry - there's a straight fuel hose to the bulb and to the engine. I asked the shop if installing a quick disconnect and running it dry would help and the answer was NO.I wouldn't be able to get all the fuel out. What do snowbirds do if they have to leave their boats idle for 6-7 months? Fogging is fine for corrosion protection but this varnishing is BS. (Ever notice that you can't find a way to e-mail the Yahama egnine folks?)Oh, the boat has a 40 gallon tank and it's full.

 

[LubeDude]

Re: 2003 Yahama 115 carb "varnishing"

How long have you had this boat? Is there a posability that there may be some ugly stuff lurking in the bottom of the fuel tank? Pump about a quart into a clear glass jar, then let it sit overnight and see what youve got! May not be enought to plug up your filter, but enough to gum things up after sitting for awhile!

 

[seahorse5]

Re: 2003 Yahama 115 carb "varnishing"

You can run the motor every few weeks, but if it has 6 month old fuel in the tank, you will still have a varnish buildup with todays fuels. If you buy fuel from a marina, it is likely the fuel is a month or more old when you pump it. Like Yamaha and other manufacturers recommend, start with fresh fuel and use their "fuel stabilizer" continuously and you won't have any further problems. Yamaha and Suzuki motors are more prone to varnished carbs than Merc and Johnsons.<br /><br />Carb cleaning for a 115 Yamaha is very reasonable at ~$200. Carb kits alone are close to $100, depending on which year.

 

[BRIAN03]

Re: 2003 Yahama 115 carb "varnishing"

The fuel is different. Our shop policy is. If the boat is at our shop more than two weeks we treat the fuel. We recommened to customers if the boat sits more than 4 weeks treat your fuel. The fuel today turns much faster.

 

[jim dozier]

Re: 2003 Yahama 115 carb "varnishing"

I don't buy that your carbs gum up that fast unless there is <br />A: Something wrong with them that hasn't been fixed yet.<br />B: Something in your tank that is not supposed to be there.<br />C: You have some other problem with your engine that is exacerbated by normal expected amounts of gas deposits.<br /><br />Give us some more history on why you've had to take the engine into the dealer for carb repairs so often. Perhaps a simple change in your starting procedures would alleviate your problems. If I don't start my Suzuki for a month or more it helps to squirt some premix into the carbs for the first start up, but I don't need to after that and it runs, starts, and idles fine.

 

[Capt Jim]

Re: 2003 Yahama 115 carb "varnishing"

Basically, I've had to just start it up in the storage lot where I keep it. They've got a water hook up so no problems. I pump up the fuel bulb, give it some choke and hope for the best (which hasn't happened much).<br />I went to the shop today and the tech showed me the carbs and they look nasty. Evidently I just got a load of bad gas and didn't get stabilizer into it soon enough. I was told to get the boat into the water this weekend and burn the tank just about dry, put fresh gas in it and use Merc stabilizer along with a Merc water treatment.<br />The shop also said to stay away from StarBrite. It doesn't work worth a darn. They also recommended AGAINST a fuel disconnect and running the carbs dry. Running the engine out of fuel also cuts off the lubrication (oil Injection).<br />And the saga continues.<br />Jim

 

[dogralph]

Re: 2003 Yahama 115 carb "varnishing"

I have a 90 115 - I had issues with the carbs and had them rebuilt and went back to brand new - starts usually on the first crank whether I have beed running it every weekend or it has sat.<br /><br />I would look at the fuel as the problem provided you feel they did a good job rebuilding the carbs.<br /><br />The 115 have major issues starting if they don't choke 100%...There is a gasket that sits on top of the carb and the bottom of the air intake plastic housing. I was getting bits of it caught in the choke plate and it would give me trouble starting...my mechanic removed it and now I have no problems

 

[jim dozier]

Re: 2003 Yahama 115 carb "varnishing"

Most books don't recommend running the carb dry because it dries out the seals and gaskets in the fuel system. As much trouble as you've apparently had, I would look into not just removing/burning off the bad gas but having the tanks rinsed and cleaned. Put new filters in while you're at it.

 

[gss036]

Re: 2003 Yahama 115 carb "varnishing"

I have a 1989 Mercury 200 hp stroke and have used Starbrite in it every winter, I have a 115 gal tank and put in quart at a time. I never have any problems w/varnish. (I leave the fuel fill cap off when the boat is is the barn and stuff a shop towel in it to keep anything out, this lets the mosture rise and come out instead of condensing in the bottom of the fuel tank, I use to have to chage the seperator filter about every 3-4 months, now I just change in the spring.) I do use the SeaFoam decarb method about every 100 hours. If I had a smaller tank I would probably use just SeaFoam for both. Just my 2 cents.

 

[Solittle]

Re: 2003 Yahama 115 carb "varnishing"

Capt Jim - The other guys have pretty much covered it. The only thing I might add is for you to install a water seperator/filter in the gas line or if you have one change the filter. The type of filter should look like an automotive oil filter and not one of those cylinder things the diameter of a cigar.<br /><br />And yes I too think your wrench is trying to get into your wallet.

 

[rodbolt]

Re: 2003 Yahama 115 carb "varnishing"

hello<br /> are you premixing or using oil injection? premixed fuel in a 40 gallon tank will go bad in a few weeks. if its so nasty they say to "burn it all out" then I would just have them pump the tank. usually, if in fact it is a varnish problem you will burn a piston long before you burn 40 gallons. nothing like selling a new motor only to have it back with a smoked piston and the engine manufacturer wont cover hull related fuel problems.appearently you saw the carb nasties with your own peepers so I dont think the tech was just trying to get in your wallet. install a yamaha water fuel seperator as well. as far as running any engine dry I dont like it. you still cannot get the last 1/4" of fuel from the bowl and that is where the idle and main jets lie. if yopu must the carbs can be manually drained. that is what I do. no gaskets are at the fuel level and if its not there it can go bad. now for the lube. if you premix never run it dry. if your using the oil injection then it injects oil at the reeds behind the carbs regardless of fuel flow. just not much oil. that is why we fog them for storage. well enough rambling for now. just remember once fuel goes bad its bad no matter what additive you use. if its in a two stroke it will attempt to stick to the piston skirts.<br /> good luck and keep posting