TN-28 Carb Adjust? HELP!

[smmyjr44]

I have finally completed this rebuild process and this old 5hp TN-28 is chompin at the bit! When I start it I am assuming it should be in neutral. How do I adjust the carb once I have it running? What should the initial settings be? Are the adjustments made with the motor in neutral? I am in need of some experienced direction with this model.

Thanks, Paul in Michigan

 

[HighTrim]

Re: TN-28 Carb Adjust? HELP!

Both needles are set at about 3/4 turns out from lightly seated, If I remember right the low ends up being about 5/8's of a turn out from lightly seated every time I have ever done one.

Start with the high, take her to WOT on the water, then in small increments turn it in, CW, until it wants to die or backfire, then back it out 1/4 turn. Within the 1/4 turn is the ideal setting. I also tend to lean a little rich to preserve the motor.

Same with the low speed, only now you are at an idle. Turn the needle in, CW, until it wants to die or you get a mild backfire. Then back it out, CCW, a 1/4 turn. Within that 1/4 turn is the ideal idle setting. Turn it in small increments and give the motor time to respond.

Have you read this?

http://www.pochefamily.org/outboard/CarbService.html

 

[smmyjr44]

Re: TN-28 Carb Adjust? HELP!

I have read that article, but it did not help with the adjustments. I am not familiar with the term "WOT"? Can you explain that? And these adjustments are made with the prop engaged or the motor in neutral?

Thanks Paul

Both needles are set at about 3/4 turns out from lightly seated, If I remember right the low ends up being about 5/8's of a turn out from lightly seated every time I have ever done one.

Start with the high, take her to WOT on the water, then in small increments turn it in, CW, until it wants to die or backfire, then back it out 1/4 turn. Within the 1/4 turn is the ideal setting. I also tend to lean a little rich to preserve the motor.

Same with the low speed, only now you are at an idle. Turn the needle in, CW, until it wants to die or you get a mild backfire. Then back it out, CCW, a 1/4 turn. Within that 1/4 turn is the ideal idle setting. Turn it in small increments and give the motor time to respond.

Have you read this?

http://www.pochefamily.org/outboard/CarbService.html

 

[F_R]

Re: TN-28 Carb Adjust? HELP!

WOT means Wide Open Throttle. On a boat. On the lake. In gear. Watching where you are going.

I agree the slow speed needle will be very close to 5/8 turn open. It is very touchy. 1/4 turn either way will be way too much. BTW, it will spit in your eye when it sneezes.

I'd begin with the high speed open more, about a turn or turn and a half. You can always lean it out when you get it WOT. But that's just me.

 

[smmyjr44]

Re: TN-28 Carb Adjust? HELP!

Thank you very much, the initial startup and adjustments will take place in my barrel. Any additional advice you could offer would be greatly appreciated.

Paul in Michigan

WOT means Wide Open Throttle. On a boat. On the lake. In gear. Watching where you are going.

I agree the slow speed needle will be very close to 5/8 turn open. It is very touchy. 1/4 turn either way will be way too much. BTW, it will spit in your eye when it sneezes.

I'd begin with the high speed open more, about a turn or turn and a half. You can always lean it out when you get it WOT. But that's just me.

 

[HighTrim]

Re: TN-28 Carb Adjust? HELP!

BTW, it will spit in your eye when it sneezes.

That's funny, actually happened to me while I was down there tinkering