Is that a sign of a problem? 30 hours on motor, has had first oil change. Smokes first start of the day for a few seconds, sometimes a lot of smoke but doesn't last long or smoke anytime thereafter. Anything to be concerned about?
Is that a sign of a problem? 30 hours on motor, has had first oil change. Smokes first start of the day for a few seconds, sometimes a lot of smoke but doesn't last long or smoke anytime thereafter. Anything to be concerned about?
How are you leaving the motor when it is not being used? If tilted down it is not abnormal for a bit of oil to get into the combustion chamber and smoke at start up and for a short while thereafter. Try tilting the motor up just a tad and see what happens.
Ok makes sense, I'm trimmed down as the boat sits on a lift. I can trim it up though, will give it a shot. Thank you!Originally Posted by jethro1
Yeah try and keep the motor level or tilted up. If left down oil can make its way to the bottom cylinder and give that puff of smoke.
may be too much oil, make sure you arent making oil
2004 Ranger 521vx Yamaha 250 SHO
this makes zero sense. oil doesn't sit in the head. oil sits in the bottom of the motor. how would the oil get into the combustion chamber exactly?
2004 Ranger 521vx Yamaha 250 SHO
Ah. You must be from Missouri. Read this. Now what do you think? Sense or zero sense?
In the good olden days there were many radial aircraft engines used on airplanes at your local airport. Those buggers would smoke like crazy when initially started. Reason being that oil would migrate past the piston rings on the cylinders that were facing downwards and get into the combustion chamber. After a minute or too the oil would all burn off and the smoking would start. If one did not know what was going on the motor would be thought to be toast.
This probably isnt the problem. And if it is you have a piston ring problem. My sho sits level for long periods of time level and has NEVER smoked.
2004 Ranger 521vx Yamaha 250 SHO
If it were mine i would have a good shop look at it. A motor with 30 hrs on it should never smoke.
2004 Ranger 521vx Yamaha 250 SHO
There is a pretty good reason why Yamaha posted the advice they did.
OP can simply test his motor himself. If he trims the motor up a tad when it is not running and it stops smoking then he knows what was causing it. If it keeps on smoking then the reason for the problem is unknown. In which case a visit to his mechanic would be useful.
Flip you new car upside down for a few hours, then upright it and start it. (If it will even crank over because of the oil in the cylinders hydrolocking it) same principal. Steel rings will let oil by with gravity's help. Cj
2002 X19 200HP OX66 HO Vmax,HPDI lower, it lives, thanks Hydro Tec.
Speaking of turning it upside down, there were piston aircraft motors that had cylinders facing downward. The pilot would have to rotate the motor a turn or two to make sure it was not hydrolocked before he engaged the starter motor. If so, a connecting rod could be bent. If it was hydrolocked, one of the two spark plugs was removed to let oil drain out. The motor would then smoke like a fiend upon start up, as if the rings were worn out. Just the nature of the beast.
Yep, thought about mentioning that, I believe radial engines will smoke on a few cylinders also on start up and they counted the number of prop rotations before hitting the ignition switch to light them off, so as to not blow the head off or bend something. CJSpeaking of turning it upside down, there were piston aircraft motors that had cylinders facing downward. The pilot would have to rotate the motor a turn or two to make sure it was not hydrolocked before he engaged the starter motor. If so, a connecting rod could be bent. If it was hydrolocked, one of the two spark plugs was removed to let oil drain out. The motor would then smoke like a fiend upon start up, as if the rings were worn out. Just the nature of the beast.
2002 X19 200HP OX66 HO Vmax,HPDI lower, it lives, thanks Hydro Tec.
I completely understand what you are saying.... but then why doesn't my SHO with almost 200 hrs NEVER SMOKE. and it sits at full trim down for days at a time! its up to the owner, if he's cool with his brand new $18-20k motor throwing smoke... then SEND IT!
2004 Ranger 521vx Yamaha 250 SHO
I don't recall anyone saying that all four strokes will smoke upon start up if they are trimmed down for a period of time before next start up. Yours apparently does not. I suspect that the vast majority do not or we would be hearing more about this.
However, some will. For those that do smoke during start up, after having been left trimmed down, leave the motor trimmed up a tad. If the smoking stops, the issue has been found and corrected. If it still smokes then a further investigation is needed.
No two Yams of the exact same model and born on date will be precisely alike. They may have differences. Those differences do not mean there is a problem. This can and does drive folks with twins, triples or quads crazy. One motor sounds different than the other. One motor pees different than the other. One motor trims up faster/slower than the other. One motor turns a half turn more before starting than does the other. One motor has 15 psi water pressure at 3500 RPM while the other has 16 psi. One motor burns 8 gallons an hour at 3500 RPM while the other burns 8.5 gallons an hour at 3500 RPM. One motor outputs 14.7 volts while the other outputs 14.5 volts. Nothing wrong with any of the motors doing this, but some owners feel otherwise.
Last edited by jethro1; 05-24-2017 at 07:58 AM.
My BMW motorcycle (K1200 LT) has a horizontal inlne four cylinder engine. If left on the side stand it will smoke on start up. Placed on the center stand, no smoke. And of course my HDPI will smoke unless trimmed up.
2007 Skeeter 21i 300HDPI
Oh now you really did it!!!It'll look like something from a cheech and chong movie! CJ
2002 X19 200HP OX66 HO Vmax,HPDI lower, it lives, thanks Hydro Tec.
Stringwise,
Have the dealer check out your motor pronto. Mine did the same thing and when I checked the oil it was milky. When they checked out my motor it had a pinhole by one of the cylinders in the block allowing water and oil to enter the piston. The dealer put a whole new head on my engine and it had 50 hours on it, and all under warranty of course. I now have 360 hours on my 200SHO and love that motor.
Regards, Bob
thats crazy! Glad they figured it out
2004 Ranger 521vx Yamaha 250 SHO
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