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Tohhatsu 9.8 2009, starts Rough then dies

Fishn4Funn

Fishn4Funn

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I keep hearing about cleaning the Idle Circuit. Without a Service Manual, can anyone describe how this is done and where it is located? Or a link to see it so I can really understand it?
 
You would need to remove the carb, completely disassemble it, submerge it for 4 hours in carb dip (available at auto parts houses in 1 and 5 gal cabs), then blow it out, reassemble, and reinstall.
 
Even though it runs at upper rpms? Could it not be just an idle adjustment? Actually I tried this and I adjusted it up so it was running at too high an idle speed so I shut it down quick. I just bought this used. Sounds like it has been sitting since Springtime, at least that's what the guy told us. OK I'll have to do it Sunday, this weekend we're fishing. Thanks
 
If the carburetor passage ways are " plugged " then no amount of adjusting will help.-----------Go over it carefully and clean out all the wee passage ways and jets.
 
racerone, any special tools we'll need? I get the feeling, since I don't have the service manual that a really tiny and fine bristle brush, or some such tool might be needed. Otherwise how would one get into those passageways? Thanks
 
No shortcuts to carb work. No special tools needed, either. There is no external adjustment to be made, so thorough and proper cleaning is called for. The proof of the problems in the idle circuit is that once you increased the throttle stop enough to run on the high speed circuit, it runs well... but coming into the idle circuit, the carb does not deliver enough juice, and the motor stalls. Do not use any probing tools inside, or you will cause scratches in areas that shouldn't be scratched, and that will result in weird flows, which may ultimately end in you buying a new carb.
 
Thanks guys, and would we need to replace the gaskets? And if so where to buy? I've never done one of these, other than waaaaaaay back in high school. SO that's what I'm remembering.
 
Usually you don't need a kit. the only gasket of significance is the o-ring for the bowl. However, if you do need a kit, you would order the Carburetor repair kit. Kit includes gaskets, float & needle valve. Fits: 8hp & 9.8hp 4-stroke models, Part # 3V1871220M, $34.75, from any dealer, including me. If unsure about your skills, get to a dealer to help you.
 
Thanks again, I won't have any trouble so long as all it is is a good soaking and an O-ring. I would like to ask your opinion about service manuals, though. I also have a 1997 Johnson 70hp and ordered a used OMC service manual and am unsure if that is an acceptable manual. It seems quite specific. Or do you recommend another publisher for clarity of steps and procedures?
 
I usually recommend the Manufacturer's manuals. That includes, OMC, Tohatsu, and yes, even for a Chevy :)
 
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