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Tohatsu 6hp runs OK but will not idle

G

Geoedgar

New member
I just cleaned my Tohatsu 6hp carb and all jets look OK. It starts easily on full choke and runs well after warm up but dies when you close the throttle right down.
 
I took it apart and sprayed all jets and orifices with carb cleaner. As far as I could see everything looked clear. Not sure how many turns I should open the idle jet though, I tried various from one and a half to four but it didn't seem to make much difference
 
Generic aerosol carb spray is not aggressive enough to clean varnishing from the narrow passages. You must do a total disassembly (including the jets and emulsion tube nozzle), then a 4-hour room-temperature soak of all non-rubber parts in real carb dip (available at auto parts houses in 1-gallon cans with a dip basket), and THEN a liberal and aggressive spray-out with the generic acetone-based carb spray (use a whole can if needed) to dislodge any loosened varnishing. When reassembling, verify float height, and adjust if necessary. Is your model 6A2, 6B, or 6C? The A2 carb will be more tolerant of minor varnishing, and will have a more stable idle.

It is not necessary to drill out the brass EPA plug that hides the pilot jet screw, but if you did, reset the pilot to the same number of turns where it was originally set (they are set by instrument at the factory). If you don't have that reference, start at about 2-1/2 turns out, run the motor at warm idle, with a very accurate shop tach attached, listen with your spider-hearing, and adjust as you would any older-style (adjustable pilot) idle mixture. That is... Set the idle stop to specs, then adjust pilot for increased speed... then reset the idle stop, then repeat about 3 or more times, until you have minimum idle stop with the pilot screw set for highest idle speed, then richen about 1/8 turn for stability.
 
Thanks Paul,
the model is 6C. I checked prices for the solvent kit- $280- I think this is for way more solvent than I need- is there a cheaper solution (no pun intended)
 
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