excessive smoke

[500whp335i]

ok so i had the boat out all day and it runs great, got it up to 50-55 on a river very responsive throttle everything was great. But in no wake zones ~5mph about 2000 rpms the boat smokes like a chimney, i did the oil bypass conversion and running 50:1 ratio, i know it will smoke but it seems excessive to me and everyone i pass tell me my boats smoking this video is probably the least it smokes while going through a wake zone, it also smokes at idle the same if not more. When im cruising and come to a wake zone it can take up to 20 seconds before i notice the smoke. I pulled the plugs when i got home and noticed the port side plugs seemed cleaner/ less fouled than the starboard side, i found that a little weird... any ideas? http://youtu.be/oPPlgNkV6pc

 

[Dr Honda]

If you want the smoke to go away... put the pump back on.

I know that's not what you want to hear... but it's the truth. BUT... if your engine has never been rebuilt... your pump gear could be on it's last leg. (Hard decision to make)


With that said... you could try changing your port side temp sender. If yours is going bad... it will run rich.

 

[Seadoobuddy]

Listen to the Dr.
................

 

[500whp335i]

If you want the smoke to go away... put the pump back on.

I know that's not what you want to hear... but it's the truth. BUT... if your engine has never been rebuilt... your pump gear could be on it's last leg. (Hard decision to make)


With that said... you could try changing your port side temp sender. If yours is going bad... it will run rich.

Yea its original motor, i just find it weird that the starboard side plugs were much more fouled up than the port. Just realized the 240 doesnt have switch boxes... and the head temp sensor is good on the port side, i metered it out..

 

[500whp335i]

Listen to the Dr.

Also i thought 50:1 is high.....shouldn't it be 40:1????.....might be part of your smoke problem.

40:1 is a richer oil mixture.. 40oz of gas to 1oz of oil vs. 50oz of gas to 1oz of oil...

 

[racerxxx]

Seadoo is 40:1 premix ratio that's what I run my Speedster at(no oil injection on it), I can go thru a no wake for 10 minutes and barely have any smoke.

 

[Seadoobuddy]

40:1 is a richer oil mixture.. 40oz of gas to 1oz of oil vs. 50oz of gas to 1oz of oil...

Yes I know. I realized that right after I typed it. Also saw that it's Merc motor

 

[500whp335i]

Seadoo is 40:1 premix ratio that's what I run my Speedster at(no oil injection on it), I can go thru a no wake for 10 minutes and barely have any smoke.

THATS WHAT I WANT LOL!!! i wouldnt care really but when you have hot broads on the boat its embarrassing lol

 

[racerxxx]

I just looked at your plugs, if you idled in that is not a good way to check the plug, they'll always look wet. You need to do a WOT plug chop. Run the boat WOT for a really good run, the pull the lanyard, pop the lid and pull the plugs and then check them. Just make sure you have the real estate to do it.

 

[racerxxx]

THATS WHAT I WANT LOL!!! i wouldnt care really but when you have hot broads on the boat its embarrassing lol

Dude, you gotta be quick on your feet, tell them it's an automatic mosquito repellant, that you don't want those nasty chemicals on their hot bodies!!!!!!! Plus, OFF doesn't taste good:thumbsup:

 

[500whp335i]

I just looked at your plugs, if you idled in that is not a good way to check the plug, they'll always look wet. You need to do a WOT plug chop. Run the boat WOT for a really good run, the pull the lanyard, pop the lid and pull the plugs and then check them. Just make sure you have the real estate to do it.

but do you notice how unevenly they are beginning to foul up?

 

[500whp335i]

Dude, you gotta be quick on your feet, tell them it's an automatic mosquito repellant, that you don't want those nasty chemicals on their hot bodies!!!!!!! Plus, OFF doens't taste good:thumbsup:

:lol: thats what i tell my neighbors when i come home and run it on the hose!

 

[racerxxx]

but do you notice how unevenly they are beginning to foul up?

I'm curious, 2 of the plugs look good in each pic, the ones closest to your plam. If I had to guess, they're from the MAG cylinder(front).

Wait a second, is this thing a Merc?? If so scratch the above. Sorry used to the Rotax mills, not the Merc's

 

[Dr Honda]

You could also make sure the TPS is set properly. It's outlined in the manual.

 

[500whp335i]

You could also make sure the TPS is set properly. It's outlined in the manual.

roger tony, the plugs look ok to you even though they are fouled up differently?

 

[go-hokies]

If you want the smoke to go away... put the pump back on.

I know that's not what you want to hear... but it's the truth. BUT... if your engine has never been rebuilt... your pump gear could be on it's last leg. (Hard decision to make)


With that said... you could try changing your port side temp sender. If yours is going bad... it will run rich.

Sorry... but, with all due respect to the doc, have offer second opinion and disagree. Having done the conversion and running 50:1, for over a month, I can tell you that it shoud not smoke that much... I have only had one commet about having a 2 stroker, and that was from fellow 2 stroker that noticed the smell, not the smoke.

If mine smoked like that, they would have kicked me out of my marina... and i would have immediately convert back. Think of all the other pre-mix two strokes out there.... when operating "within normal limits"

I can take a video this weekend, but think the root cause of the smoke is yet to be found... Would look at some of the other suggestions especially when you have that much difffernece in Port / Starboard banks... its all 50:1

Mike

 

[500whp335i]

Sorry... but, with all due respect to the doc, have offer second opinion and disagree. Having done the conversion and running 50:1, for over a month, I can tell you that it shoud not smoke that much... I have only had one commet about having a 2 stroker, and that was from fellow 2 stroker that noticed the smell, not the smoke.

If mine smoked like that, they would have kicked me out of my marina... and i would have immediately convert back. Think of all the other pre-mix two strokes out there.... when operating "within normal limits"

I can take a video this weekend, but think the root cause of the smoke is yet to be found... Would look at some of the other suggestions especially when you have that much difffernece in Port / Starboard banks... its all 50:1

Mike

i was harassed by my marina thats why i pulled it out of the water... thats whats confusing me the difference in the banks with the plugs...

 

[500whp335i]

it smoked like that when it still was on the oil pump

 

[Dr Honda]

roger tony, the plugs look ok to you even though they are fouled up differently?

I have mixed feelings about the plugs.

They aren't "Fouled" at all... and when you read a plug, you look at that insulator. It looks good, and about the same on both plugs. But... they do look a little glossy (wet) and the dark color I see on the outer edge looks like wet oil and carbon.

A final thought on the plugs... this is a 2-stroke... so they aren't all going to burn the same, and the oil will make it hard to read at times.


I remember seeing your thread about metering the temp sender... but since you are tryin to minimize smoke... I think I would replace it anyway. And actually... I am replacing mine. My new engine starts, and runs fine... but I figure it couldn't hurt... and since they are known to fail... even if mine is good now... it will be nice to have a spare.

If you look at the sticky thread, about the best tune-up... I made a post about a guy on eaby, who is selling the sender you need for $30 shipped.




*****EDIT******


I just looked at the Vid, and saw that you were smoking before the conversion.... so, without a doubt... I would just change the port temp sender, and check the the TPS.

The thing with this is... it can be a combo of a few small issues... but no single one will look bad. (That's why it still runs OK)

I would also verify the ignition timing. A few degrees low at idle could cause excessive un-burnt fuel.

 

[Dr Honda]

Sorry... but, with all due respect to the doc, have offer second opinion and disagree. ................


Mike

I take no offence to any info/opinions. I am far from perfect... and I'm "New" to the Merc engines.

So please... always say what you are thinking.

 

[El Toro 33809]

Just curious, what oil are you using?

 

[500whp335i]

Just curious, what oil are you using?

i tried quicksilver premium plus, and now i just started using amsoil hp marine, it has the lowest ign. temp so i figured that might help... ill meter out and check the tps today before work and report back.. tony that was the correct sensor i posted about correct? thats the head temp sensor, thats the only one on the port side i saw

 

[Dr Honda]

Yes it was. (as I remember) There are 2 temp senders. One is a single wire, and one has 3~4 wires. The one you want to replace is the one with 3~4 wires.

One thing... Just because it checks OK "on the bench"... doesn't mean it's reporting the correct thing to the ECU when it's under real conditions. Vibration, and heat can make electronics have intermittent issues. AND... since the engine will run with that disconnected... I would just replace it. (and I am in my personal boat)


Oh... just thought... when you put it back into the head... did you use any thermal or dielectric grease? That will help transfer heat.

 

[500whp335i]

Yes it was. (as I remember) There are 2 temp senders. One is a single wire, and one has 3~4 wires. The one you want to replace is the one with 3~4 wires.

One thing... Just because it checks OK "on the bench"... doesn't mean it's reporting the correct thing to the ECU when it's under real conditions. Vibration, and heat can make electronics have intermittent issues. AND... since the engine will run with that disconnected... I would just replace it. (and I am in my personal boat)


Oh... just thought... when you put it back into the head... did you use any thermal or dielectric grease? That will help transfer heat.

nope i actually cleaned it off and put it back in... what leads on the tps? there are 3 the most im getting of a reading is .093 vdc, i have the two brown and black striped wires disconnected from the temp sensor like it says

 

[500whp335i]

no matter how much throttle i give it the most i can get from the tps sensor from any wire combo is .098 vdc...