90-Runs for 10 min dies

[greasyshaft]

I think OP has given up on us

[zenoahphobic]

I don't know this motor either, but what is the concenses, has it got an O2 sensor or not?

[greasyshaft]

no .

[greasyshaft]

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no




















but it does have a spok plog

[zenoahphobic]

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no




















but it does have a spok plog

Thanks, didn't see enough info to determine that.
"spok plog" - didn't see how that was determined either, sorry

[TownsendsFJR1300]

The only manual that I could find had a price of five pounds. I can confirm that larger 2 stroke 2002 Yammies use O2 sensors. Two things that I do know, is that I have never worked on a motor that did not have one, and that just because someone here ask "why would a carburetor engine use an O2 sensor" does not mean that the engine does not have one. The person edited his post after I responded, because the question was foolish.

As a side note, my first new car, last of the carberated 305 CI, 1986, Chevy Monte Carlo, had an O2 sensor.

Of course that comparing apples to oranges but a carbed engine can indeed utilize an O2 sensor..

A bunch of "chest bumping" going on and de-rails, BUT Rodbolt did point him in the direction of the fuel system (post #17).

It would be nice to know if he followed up on that or found the issue..

[TownsendsFJR1300]

My 86 Camaro coupe with the stock Z28 engine had an O2 sensor as well, along with a Rochester Quadri jet carb, probably the same 305 block as your Monte. Now it is possible that the auto industry was under more stress to manage pollution than was the OB industry, which might be why all OB engines might not have them as soon as auto's did, but no one here can either confirm or deny that this 90hp engine does not use one, and I can not either. Yamaha should have these diagrams for the use of all.

Yep, mine was a Rochester as well.

Two stroke motorcycles have been outlawed in the US for years due to emissions. Car emissions way more so. My 07 Yamaha 4 stroke motorcycle has TWO CATs and an O2 sensor. The ECU does adjust the FI with input from the cats, air temp sensors, etc.

OB two strokes lasted a lot longer (and of course still exist) with the advancement of electronics' etc.

Anyway, looking at the parts fisch for this engine, I don't see any O2 sensor;

http://www.boats.net/parts/search/Ya...ING/parts.html

http://www.boats.net/parts/search/Ya...CAL/parts.html

[hiflutin]

Hey guys thanks for all the replies?
Ended being a broke Pink wire inside the cowling
The motor was getting hot, cdi was thrown alarm, knockn the rpm's down
But the audible was not going off cause the broke wire,
Now I have other probs, will start new thread