Yamaha outboard help

[the Lackster]

Gonna throw this on here and see if anyone has a suggestion. So what i got, 1993 yamaha tlrr 70hp 2 stroke. It cranks fine, idles fine but when i ease into the throttle it will bog down at about 7-8 mph. If i keep pushing it it will cut it off. Now, this only happens in cold weather. If i get in it in the afternoons even on a cold crank it will run wide open with no hesitation. The problem literally only happens when the ambient is under 35 or so. Once it idles for like 30 minutes it will run like its supposed to.
- just replaced fuel lines
- drained tank and cleaned it
- new yamaha spec sparkplugs
- drained carburetor bowls, fuel was clean
- check coil packs with meter, all checked out
Any help or suggestions would be greatly appreciated. Thanks guys

 

["J"]

you have an electric choke on that?

 

[giles]

you have an electric choke on that?

I agree with this. Sounds like a choke issue.

 

[the Lackster]

you have an electric choke on that?

J that on has the prime start assembly on the #2 carb

 

[jagermeister]

Fuel tank properly vented?

 

["J"]

J that on has the prime start assembly on the #2 carb

Has always been doing this or it just started doing it?

 

[giles]

Could just be the added ethanol to the fuel today. 93' wasn't designed for what you buy today. Unless you are feeding it ethanol free fuel.

 

["J"]

The whole runs rough in cold temps vs warmer temps. Seems it would rule out most issues except for the cold idle circuit.

I‘m PM’ng you a link, it’s too a forum for your motor. They’re some good folks too answer your questions. You may have too register too post the question though. I’d basically copy and paste what you did here and give them a shot. Chances are they’ve seen or know what too do.

 

[the Lackster]

The whole runs rough in cold temps vs warmer temps. Seems it would rule out most issues except for the cold idle circuit.

I‘m PM’ng you a link, it’s too a forum for your motor. They’re some good folks too answer your questions. You may have too register too post the question though. I’d basically copy and paste what you did here and give them a shot. Chances are they’ve seen or know what too do.

Thanks man

 

[the Lackster]

Could just be the added ethanol to the fuel today. 93' wasn't designed for what you buy today. Unless you are feeding it ethanol free fuel.

Im sure it doesn't help.

Has always been doing this or it just started doing it?

To be honest i have had the boat for 11 years and never really ran it between September and march. This is the coldest i have ever had it out but i have never had issues like this before.

 

[Big Weff]

Might just need to re-sync the carbs and adjust your set screw to give them a little more air in your mix. I have a yamaha 150 but have never touched the motor aside from fogging it going into winter so I might just be talking out of my ass haha

 

[5Cent]

From boat mech. buddy who is Yammie certified:

Out boards with carbs aren't really jetted to be run under 40 typically the water is hard! Would have to find out what kind of choke it has as well I would guess that's the issue. Some are electric with a blue wire others are mechanical and lastly they are automatic with the wax pellet design

 

[the Lackster]

From boat mech. buddy who is Yammie certified:

Out boards with carbs aren't really jetted to be run under 40 typically the water is hard! Would have to find out what kind of choke it has as well I would guess that's the issue. Some are electric with a blue wire others are mechanical and lastly they are automatic with the wax pellet design

Thanks for response! Mine has the prime start on the second carb.

Update on the issue. I removed the airbox Sunday and noticed the bottom carburetor had a good bit of oil/gas mix in the chamber for the bottom carburetor. @"J" i posted the issue on bass boats central and a guy on there said the bottom carb had a stuck float "gas in air box" and probably a gummed up pilot jet "won't run when its cold". Im gonna try tonget that fixed this week and go from there.

 

[5Cent]

I highly recommend Seafoam for a normal fuel addition.

 

["J"]

Thanks for response! Mine has the prime start on the second carb.

Update on the issue. I removed the airbox Sunday and noticed the bottom carburetor had a good bit of oil/gas mix in the chamber for the bottom carburetor. @"J" i posted the issue on bass boats central and a guy on there said the bottom carb had a stuck float "gas in air box" and probably a gummed up pilot jet "won't run when its cold". Im gonna try tonget that fixed this week and go from there.

Good too hear they chimed in with a fix. Those guys on there have a combined shit ton of experience with boat motors. Here’s hoping you get it figured out.