Smoking Yamaha

[sycmate2]

just got a 1999 yamaha 115hp. Runs well, noticed though when i was flushing it at home was very smokey when iwas flushing motor at idle. any reasons?? problems?

[sycmate2]

is it posible to have the manual choke on? where do i check

[Flightmanager]

Some models use the ignition key to operate the choke manually , ( usually by pushing it in ) . Remove the cowling , and operate the choke. You should be able to see the choke linkage operating .

As for the smoke , there could be a few reasons. Was it dark smoke , with a strong smell of petrol , or a light "sweet" smelling smoke? Have the carbs been serviced recently? If the motor has been sitting unused for any length of time , gum may have formed in the carb internals , affecting needle valves and floats , galleries etc. Are you using the correct 2 stroke mix (50:1) , or does this engine have oil injection ?

Ross

[sycmate2]

wasnt a dark colour and im mixing the oil 1:50. Not sure if i lifted the warm up lever would have got rid of smoke. didnt want to make to much noise at night. Used the motor twice in last few days. didnt notice that much smoke last time i flushed it

[Flightmanager]

Two strokes when they are cold will blow smoke , this is not at all unusual. If , while at operating temp it still blows a lot of smoke , further investigation would be warranted.

Ross

[sycmate2]

na only when it was flushing. hopefully because i only started it and didnt get to rev it a little

[chrisg]

Hi dream

If your running premix you may find its a bit smokey flushing. Basically it will be slightly rich and as theres no big revs to clear the carbs you get a bit of smoke. Never rev more than 1500rpm on flushers anyway.

Remember smoke usually means a touch too much oil which is not a bad thing!

Chris

[phill9]

I dont know about your motor mate but every yammie I have owned runs at 100-1 not 50-1 premix so it might pay to ask your yammie dealer.

[Wastin Time]

just got a 1999 yamaha 115hp. Runs well, noticed though when i was flushing it at home was very smokey when iwas flushing motor at idle. any reasons?? problems?

I have a similar problem, usually when starting it after being idle for long periods. I have put it down to maybe slight over oil in my mix (50:1). I have a 98 model 115 hp.

it is due for a service, so will double check with my service centre

[chrisg]

Yours is probably the same issue Wastin....realistically oil mixture at idle should be 70:1+....but with premix this would be too thin under load and the best compormise of 50 :1 is used. Oil injection systems change this ratio according to revs (and model) hence less smoke. Johnsons VRO 2 injection was set at 60: and can still be a bit smokey at idle......acceptable if metered by the system but there's no play in that and 50:1 is much safer for pre-mix.

All that said, to the original question, I agree yammies are generally 100:1. Check your model number with a dealer.

Cheers

Chris