What's your pre-season maintenance?

this is the first year in a couple that I'm not cleaning my carbs. I am running a product from Mercury marine in my first tank of gas. A Mercury tech advisor told me about it and runs it in every tank in his sled and boat motor. I try to avoid buying gas from places that I don't know where it came from to make sure I have quality gas (if there is such a thing anymore). But i will admit that I am a little nervous about the first ride.
 
I would suggest that the main jet can have years of fuel, varnish build up on the inside as well as the outside of the main jet. Yes it will run fine in most instantes. The burn down scenerio can happen like this, you run accross your favorite lake to a buddy's house, hang out for awhile and then later that night when temps drop very cold, and both are runnig WOT for quite awhile. At that point SIEZURE. I have seen many carbs with varnish coated main jets which run just fine, but as the varnis builds up a 300 main jet may have the opening of a 280 or even leaner. It is not much to clean the carbs on any machine. I have gone through over 28 carbs this winter. Not all on my own sleds but customers also. Al
 
Maxed out. Why don't you check the carbs after the first fuel tank and see how they look? I would be interested also. It is very odd how snowmobile carbs clog so much faster than boat motors, or even PWC's. I know the fuel we buy in the winter is not as good as summer fuel at least for lasting longer, but I am still perplexed as to why the winter fuel varnishes faster than summer fuel. Al
 
I am going to pull them after I ride it this weekend and see what they look like. I work for a gas/oil company and it is all the extra additives that are added in winter. This mechanic I know has an ethanol tester so we're going to test how much ethanol is actually in the gas too. Last summer they tested a boat motor that blew up and it had 30% ethanol. No wonder the motor blew.
 
Good point, I guess I did not consider the winter-blend fuel and issues it can cause...of which I'm not too familiar. But ethanol does what, attracts water, is bad for plastic too right? Also, some issue with older boat fuel tanks I recall...water in fuel is not a good thing.

So does anyone run their sled dry, or close to dry on fuel and then fill up in the summer and warm the engine up to get summer-blend fuel and Sta-Bil into the carbs?

And I agree, there will be lots of build up on jets just from normal use, and that build-up usually is pretty stubborn, as in when I have had to deal with in on a carb, I just tossed the jet and got a new one and viola, problem solved (it was a running issue, the bike just did not jet well, bogged, etc but ran ok once it got to WFO). Carb spray, and blowing air don't seem terribly effective that I've experienced with dirty carbs.

And really, when a motor melts down we call all guess at what the cause was, but never really know for sure, other than insufficient lubrication or excessive heat (from insufficient lubrication!). But why there was not enough lube and too much heat is the million dollar question.

Anyway, I do like beer, wrenching, and warm garages in the winter, we'll see I might just take a pass on it this year.
 
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sorry to but in but im a new yamaha owner, just wondering what you guys do when you store them do you drain the gas or store em wet?
 
IMHO you have just been lucky(so far) not cleaning the carbs.The other thing is if you keep using starting fluid you won't have to worry about dirty carbs.That stuff will destroy a gas engine as quick as anything.
 
my 2 cents

Call me lazy or stupid, but I have both a 2001 SRX and a 2003 Viper. Both have over 7000 miles and I have never cleaned the carbs. Of course I store them full ( No Stabiul ) and start them at least once a month during the summer. Some times I take them out for a rip accross the lawn on the wet morning grass. I recently had the Viper on the rack for some maintenance and looked at one of the main jets and there was zero varnish. Neither sled has been apart and the compresion is still good, SRX has like 125- 130 compression and Viper is 128 and 115 on PTO side ( normal). Oh and all I use is Yammalube.
 
Snowsnake said:
snip -The other thing is if you keep using starting fluid you won't have to worry about dirty carbs.That stuff will destroy a gas engine as quick as anything.
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Agreed.

My Yamaha manual says to not store with treated fuel unless it is known the fuel contains no ethonal. It also says to not start it periodically over summer but fog instead.

Since nearly all Michigan's high octane fuels contain ethonal, I drain and run dry in the spring and fill with in season fuel for the first ride. Pre-mix from the weedwacker down the plug hole once or twice for the first start (although I'll fool around and take notes this time around).

I too find my carbs spotless year after year and occationally skipped a year without issue. I have not found varnish build-up in any of my main jets even after skipping a year and have checked them with pin gauges to ensure thats the case. Not to say I haven't found clogged mains on poorly maintained sleds, just none in mine. The worst I see is wax and maybe galvanic corrosion.

Once cleaned the main jet with a pine needle and used a sprig of pine like a bottle brush on the bowl of a FNG's 520 at night. Actually worked pretty well.

For that and other reasons he was never invited back.
 
My 2 Cents

I acknowledge the knowledge here and I am not saying that I do anything different but both my 2 strokes run fine after all these years. Both start and run fine idle and top end.
 
like snomofo, i too pull my carbs and never find anything significant, but i've bought sleds that the carbs looked terrible when i've pulled them, and i've done carbs for people that were terrible as well, i'd rather spend an hour doing my carbs each year and know all is well then burn down and lose a week or more of the already short season and spend $500-$1000 on parts
 
JERSEYJOE said:
I acknowledge the knowledge here and I am not saying that I do anything different but both my 2 strokes run fine after all these years. Both start and run fine idle and top end.
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Actually, you are saying you do things differently which seems to work for you. I too used to be a little lazy and wouldn't go through the carbs before the first ride and also stored with a full tank. But after seeing a lot of first ride burndowns and having one myself years ago, It's fresh in season fuel since.

Also, unless you can run the sled for over a 20 minutes at speed each time you start it over the summer, you won't be burning all the moisture collecting during storage. If you see a milky discharge from the exhaust outlet, you may want to run it longer and perhaps to the point of turning on the overheat light.

I've been draining and fogging for 15 years and as it turns out, that's exactly what Yamaha recommends in my '01 owner's guide.

I hope the success of your routine continues but I just wanted to point out why I do what I do and also Yamaha's recommendations.
 
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