1986 Suzuki 115HP,Can not get up to speed.

Retired

Cadet
Joined
Jul 1, 2001
Messages
11
Problem: Motor starts well, idles OK, but "sneezes".Motor gets up to about 2500 RPM (not measured) and just mushes along. Momentarily applying choke causes a slight spurt in power, but not very much.<br /><br />History: Motor sat idle for three years not winterized causing carburetors to get gummed-up.<br /><br />The following work was done: drained fuel tank, replaced fuel lines,bulb and filter.<br />1.removed and cleaned carburetors with carburetor cleaner,cleaned main jets, pilot jets and replaced float needle valves. Set float levels.<br />2.replaced defective idle adjustment switch.<br />3.checked throttle valve switch - OK,flywheel counter - OK.<br />4.bled oil injection pump and lines. <br /><br />Naturally, fresh gas and oil were used. Also, a portable gas tank with separate lines and prime bulb were used with no change.<br /><br />Can the reed valves be at fault.<br /><br />Any help would be greatly appreciated.
 

Yepblaze

Lieutenant Commander
Joined
Jun 1, 2001
Messages
1,686
Re: 1986 Suzuki 115HP,Can not get up to speed.

I've got a 1980 dt50 and I can let you in on a couple of items I've had to deal with.<br />1) the foam in the cover was deteriorating and caused some small bits to enter the carb bowl vents and would settle out after shutting down, changing plugs, or doing any type of diagnostic procedure. It would run fine for 1 to 20 minutes then lose the main circuit in one or both carbs. I was sure it wasn't dirty carbs because I use clean gas and have large inline filter. Pulled bowls cleaned out really small bits of stuff and removed the foam hood liner along with a cleanup of underhood area.<br /><br />2) It has always had a somewhat weak spark. I've cleaned grounds and such but have resorted to reducing plug gap to .020-.025 and it's been just fine with that. I'm sure I've saved a bunch of money not replacing parts.
 

Yepblaze

Lieutenant Commander
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Jun 1, 2001
Messages
1,686
Re: 1986 Suzuki 115HP,Can not get up to speed.

When you say you cleaned the jets, did you remove the main jets and clean the emulsion tubes above them? A lot of people will not get to the emusion tubes and it will leave less than satifacory performance if the little holes on the sides of them are clogged.
 

wingnit TPA

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Joined
Jul 2, 2001
Messages
8
Re: 1986 Suzuki 115HP,Can not get up to speed.

I just had the same problem with my 200 Suzuki....among other things, I found that several of the fuel connections inside the cowling were loose and allowing air to seep into the fuel lines. Check and/or replace all the clamps on the fuel connections. I replaced all the factory clamps with wire ties and it works fine now.
 

Retired

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Joined
Jul 1, 2001
Messages
11
Re: 1986 Suzuki 115HP,Can not get up to speed.

Yepblaze,<br />Thanks for your response. Yes, I did remove the main jets and the tubes that they screw into. If these are the emulsion tubes then yes I cleaned them, however, I can not recall if I noticed or cleaned little holes on the sides of them.<br /><br />wingnitTPA,<br />Thanks, I will check all the fuel connections. The sneezing that at idle speed that I mentioned, I was told could be caused by air leaking in, resulting in a lean mixture.<br /><br />Yeblaze,<br />The foam in the cover is in good condition, but I will double check. Thanks for the suggestion.<br /><br />Retired
 

evin300

Petty Officer 1st Class
Joined
Jun 4, 2001
Messages
384
Re: 1986 Suzuki 115HP,Can not get up to speed.

Faulty reed valve or reed plate gasket can cause a sneeze also. During the down stroke no pressure is built internally, the sneeze is where that pressure went. Hope this is not the case for you, but is still not a big deal to fix.
 

Retired

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Jul 1, 2001
Messages
11
Re: 1986 Suzuki 115HP,Can not get up to speed.

Thanks to all who responded.<br />I replaced all four carburetors with used, but fully cleaned ones and the motor now runs like new.<br />Retired
 
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