HPDI Heavy smoke on startup

[dpeters7]

I hope you guys can help me out. I had a 2001 150 HPDI I bought new in 2002. I have recently sold it to a good friend.
Now the problem, after break in on start up once and a while the motor would smoke excessively. I would accelerate and it would clear itself. I brought it back to Yamaha to do the 20 hour check and they found nothing wrong. After doing some researching and looking at the motor I decided to pull the air silencer off and there was quite a bit of oil in there. Over the next few years it would be part of my winter maintenance to pull the cover at the end of the season and clean the silencer out. The motor never smoked since doing this. Now my friend has been out a few times and it has smoked heavily 3 times already. I tool him to pull the silencer off and clean it but he is questioning why the oil is there in the first place. I called the dealer again and they have never heard of this and to try Yamaha Canada, I called them and they told me it sounds like low compression which I thought was crazy as it would smoke all the time. The motor runs perfect otherwise and is very fuel efficient and is strong out of the hole. The motor now only has 100 very easy hours and did a search and it sounds like a few other posters on this site had the same issue. Can someone with the same problem explain what the dealer changed or try to help me diagnose the issue?
Just to mention a couple things I looked at are the float in the main tank for sticking and the oil level has always been between the lines. Also checked the linkage for adjustment and is ok as well.

 

[rodbolt]

Re: HPDI Heavy smoke on startup

smoking on a two stroke really has nothing to do with compression, your first clue the dealershp is clueless. find a dealer with school cerrts on the wall.
HPDI, High Pressure Direct Injection.
means the intake and exhaust ports have been closed by the upward moving piston BEFORE gasoline is injected. the gasoline,above 1500 RPM or so,has about a 1500,yes1500- 1 fuel oil mix to aid in lubricating the injectors and high pressure pump.
the oil in the air box is easy, its blowby past the reeds into the airbox,
we have fought it a long time.
the oil is injected in the reed box area and normal blowby spits it out past the throttle shutters where it collects in the airbox. there is a drain hose going from the lower bearing area on the crankcase to the airbox, make sure its clear.
its normal for HPDI to smoke at start up but usually for less than 5 minutes.if excessive I would check the oil pump shaft seals for leakage.
also test the electric oil pump output. occasionally they will stick "on" and not cycle on and off.

 

[dpeters7]

Re: HPDI Heavy smoke on startup

Thanks for the reply. It was not the dealer that said the compression was the problem it was a tech for Yamaha Canada and I found it strange as well. Anyway the smoking is very rare and when it does smoke it smokes a lot. I am going to check the drain tube. I know when you pull it off at the box it drips, but I never checked it at the other end to see if it is plugged. How do you test the electric oil pump output? And how can you check the oil pump shaft seals for leakage?
Thanks again for the help. I have not heard a response to my problem that makes sense till now.