Tohatsu 9.8 4=stroke idles with choke on only

[dickr]

Ive rebuilt the carb and removed the cap to reset the low speed jet with the same result. Runs fine at mid and top speed.

 

[TOHATSU GURU]

Re: Tohatsu 9.8 4=stroke idles with choke on only

I wonder what would cause a problem like this? I don't have any idea myself...It's sooooo complicated.

 

[pvanv]

Re: Tohatsu 9.8 4=stroke idles with choke on only

Go through the carb again. Do a proper soaking, not just a spray-out. Stay away from the idle/low speed mixture screw, as adjusting it typically either masks another problem or causes one. Verify idle stop setting. Confirm you have fresh fuel. If it works off-idle, you have confirmed adequate fuel delivery. If you still have an issue, there is a malfunction in the idle circuit of the carb that you can't fix in the field, and you will want a new carb.

 

[MasterCylinder13]

Re: Tohatsu 9.8 4=stroke idles with choke on only

I have the same problem, motor would conkout, already took carb apart and sprayed down with cleaner but did not soak, now idles rough but no longer dies, Soak in gasoline?
Thank you

 

[pvanv]

Re: Tohatsu 9.8 4=stroke idles with choke on only

The carb lives in gas, so that won't help. Soak in Tyme or similar carb cleaner.

 

[MasterCylinder13]

Re: Tohatsu 9.8 4=stroke idles with choke on only

Here in California, Carb Cleaning kits are no longer sold. I took the carb apart and did it over using an air compressor this time. Motor runs well now, off to Catalina next week. Thanks

 

[Wee Hooker]

Re: Tohatsu 9.8 4=stroke idles with choke on only

Generally speaking. Sounds like it is starving for fuel at idle. You likely have some dirt in your low speed jet and/or it needs adjustment.

 

[gary - k7gld]

Re: Tohatsu 9.8 4=stroke idles with choke on only

I wonder what would cause a problem like this? I don't have any idea myself...It's sooooo complicated.

Gotta *LOVE* those helpful non-answers - wonder how many like that a fella has to pass out to be made "Captain"?

"Better to remain silent, and be THOUGHT a fool, than to open your mouth, and remove all doubt"...

 

[TOHATSU GURU]

Re: Tohatsu 9.8 4=stroke idles with choke on only

Maybe the moderators here should start putting a stop to what as now become routine character assassination....

 

[pvanv]

Re: Tohatsu 9.8 4=stroke idles with choke on only

Generally speaking. Sounds like it is starving for fuel at idle. You likely have some dirt in your low speed jet and/or it needs adjustment.

I agree with Wee Hooker. These motors run really lean. Read that as small, high-velocity passages. The emulsion tubes are easily clogged by junk gas varnish/sludge. I have seen this in numerous 8/9.8 carbs that otherwise "looked" OK, but would not idle correctly. In order to do a thorough cleaning, one must, at a minimum, get the main jet and emulsion tubes out of the carb body, and thoroughly clean. This requires patience and skill at disassembly.

Soaking wins hands down over a spray job. But in the field, spray may be the only available tool at hand.

YMMV.