Yamaha F40 2005 carburetor problem

[Outfishing13]

I neglected to drain my carburetors on my Yamaha F40 this last season and now the engine runs terribly.

I took them apart, did a minor cleaning with some spray carb cleaner and it ran better, but still won't idle. I ordered some Berryman Chem-Dip Carburetor and Parts Cleaner and will try that out tonight.

Any other tips would be helpful.

I also got a set of vacuum gauges to sync the carbs when I put them all back together.
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[wiperhunter2]

I never drain my carbs on my main motor and don't have problems but here are a few things to remember. Unless you are buying ethanol free gas, something I always try and do, you need to always put Stabil in your gas before the end of the season. I also run Seafoam in my boat motor, all year, then in the Winter or late Fall, I also add the Stabil. It is money well spent IMO. As far as fixing your problem now, there are two guys on the site that can help you, if what you are going to try, does not work.
Geezer has helped me on my last boat when I had carb problems and mntcat1 overhauled the carb on my Yamaha kicker before I bought it from him, so he knows Yamaha motors. I know that does not help you with the problem you are having but maybe it will help with any future problems. Good luck
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[Outfishing13]

Thanks for the tips. I will definitely mix some SeaFoam in the gas this year. Normally I do that every year when I get started in the spring, but I will keep make sure I mix it in all year. I have also been told that some guys mix Stabid in their fuel all year, specially with the hot weather. I know of one place in Orem that sells "pure" gasoline. Maybe I should just go there each trip. From what I have read these older Yamaha carbs can be finicky since they has some very small ports. This is just the 3rd year of owning this motor and I have never had a problem until this year.

Got home today and the carb cleaner was delivered. Took the 3 carbs off the motor and started on them. Put the main body and jets of each carb in the cleaner to soak for about an hour.

Washed them in warm water and they all looked very clean. However, there is a very small port and orifice for the low idle. This is an orifice fed by the bottom of the bowl and it is super tiny and was clogged on all three carbs. Finally got them all cleaned out and everything spick and span and put back together.

At least I am getting a little education on this motor. I'll feel pretty good once I get it running right. Keeping my fingers crossed.

Will find out how it runs tomorrow. Waiting for the vacuum set to get here so I can sync the carbs properly.

Hope to get up to Willard this year to chase some wiper and walleye.
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[Kent]

You are way ahead of the curve from me on your engine repairing/maintenance skills. Hope your latest effort pays off.
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[Outfishing13]

I have done a little bit of work on outboards, but not enough. I have worked on carburetors here and there over the years. Chainsaws, old cars, lawnmowers and other small engines. I cleaned the carbs on my 1978 Evinrude 70 HP years ago.

I was pretty nervous taking these off and cleaning them, but they were actually pretty simple. However, there are a number of ports and orifices to get clogged with old gas that has turned into varnish. I don't have any knowledgable buddies to help me out, so I just dove in.

I did look at getting new carbs. Can you believe the total package was over $1,800. That is insane, but motivated me to give it a shot.

I expect the motor will start right up. I am hoping it will run better than before.

I guess the biggest problem is it doesn't get used enough. Guess I am going to have to fix that too. []
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[Kent]

[quote Outfishing13]

I guess the biggest problem is it doesn't get used enough. Guess I am going to have to fix that too. []

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Hey, what a great idea! I will have to give it a try telling my wife that I learned that if I use my boat more often that I will have fewer issues with the outboards and that will save us money in repairs.[] I have a hunch that she won't buy it.[:/]
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[Outfishing13]

Well, my new vacuum meters arrived today and I installed the carbs. Started right up on the third pull an it runs great. Let it warm up and hooked up the meters to sync the carbs. That is a little tricky, but I got them all really close and it is running really well.

Has anyone synced carbs before. What tricks can you share?

Time to get out and have some fun now.
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