New Tohatsu 40hp, missing/rough idle in gear

[james082273]

Every since the day I took it out of the box the motor has run awesome above idle, the idle in neutral has been fine but as soon as you put it in gear it seems like it is running on 1 or 2 cylinders. Every few seconds or so it will smooth up but then start missing again. At first I passed it on as the 25 to 1 break in mixture.<br /><br />But know I am off of the break in oil and have put new plugs in it. And still the same. Could this be a carb adjustment? Each carb has a screw adjustment that I assume is for the idle mixture. Can someone give me the starting adjustment on these?<br /><br />The butterflies seem to be in synch. It has fresh gas and as I mentioned it runs great above idle.<br /><br />Any ideals? Hopefully it is just something simple like the carb adjustment. Since I bought it online I hate to take it to a dealer .<br /><br />Thanks,<br />James

 

[james082273]

Re: New Tohatsu 40hp, missing/rough idle in gear

It is a 2003 M40D....can I at least get the starting adjustment on the idle screws?<br /><br />I think it maybe 1 turn out but I don't know for sure.

 

[phatmanmike]

Re: New Tohatsu 40hp, missing/rough idle in gear

if its new, didnt it come with a manual....?<br /><br />if you start messing with that idle mixture screw, make sure you know how to get it back where it was!

 

[rodbolt]

Re: New Tohatsu 40hp, missing/rough idle in gear

dude<br /> take it back<br /> if it ran well at first something is wrong. if you start skinning it the dealer may not like it and Tohatsu may not want to honor a warrenty claim.<br /> but if you must tweak each screw about 1/8th turn at a time.<br /> good luck and keep posting

 

[james082273]

Re: New Tohatsu 40hp, missing/rough idle in gear

Well I have learned one of the draw backs of buying online! Luckily there are a few Tohatsu sales/service places around.<br /><br />It isn't something that has just started happening, its been like that since new. I don't think it is anything serious, it runs to good off idle. <br /><br />I don't plan on going any further than trying to set the idle mixture, I just don't know what the starting point is supposed to be. With three carbs I don't want to just jump in there and start making adjustments without a good baseline. Just incase it left the factory incorrect (and I hope it did!). It isn't in the owners manual. I think I'll just grab a clymer(sp) manual when I get a chance if no one here knows.<br /><br />Thanks for the help ,<br />James<br /><br />BTW Phatmanmike, I didn't know evinrude made a 14hp in '88? I've got a '86 9.9 that I put boyesen reeds in a couple years ago that helped it put out a little more. Damn good motor, that things been through heck!

 

[phatmanmike]

Re: New Tohatsu 40hp, missing/rough idle in gear

the 14hp was a comercial/import model.. same powerhead/top end as the 9.9/15 but it has the older style lower unit.....

 

[heatherjoy]

Re: New Tohatsu 40hp, missing/rough idle in gear

what dealer online?

 

[james082273]

Re: New Tohatsu 40hp, missing/rough idle in gear

www.onlineoutboards.com<br /><br />They are a Nissan/Tohatsu dealer out of Houma, Louisiana.

 

[45_red]

Re: New Tohatsu 40hp, missing/rough idle in gear

I agree you need a manual before you start messing with adjustments. I have a clymers that covers the 40 but it's a few years old.If you change the pilot screw setting, make sure you record the exact orientation of the slotted screw head, then carefully turn it clockwise till it lightly seats.It'll probably be about 1&1/2 turns

 

[james082273]

Re: New Tohatsu 40hp, missing/rough idle in gear

Hey 45_Red!<br /><br />I hear you and thanks for the advise .<br /><br />Your manual covers an older year model? Is it still a 3cyl 40hp M40D? If so it should work fine. I'm sure they haven't changed.<br /><br />Is the 1.5 turns from the manual?

 

[45_red]

Re: New Tohatsu 40hp, missing/rough idle in gear

Yes, up to y2k;40D-1/2-2 turns;40D2-3/4-2&1/4 turns.<br />1&1/2 turns is just my guess as I can't see it from here. Depends on the size& shape of the bored hole and the tapered shaft I assume but not really sure.