Hey guys. I was wondering what to check on my motor. It starts hard when cold. And even after warmed up, if i troll it smokes alot. It is blue smoke. Wondering if there is an adjustment i need to make? Thanks all
It sound like to me, you need a good carb cleaning.
Start with ordering enough gasket kits for all your carbs.
Do one carb at a time, be sure to put them back in the same location.
As you disassemble them and remove the low speed adjustment needles, count the revolutions and write them down for a starting point for re-assembly
Take your time, soak them in cleaner over night, probe all the small venturi passages with a soft brass or copper wire, blow them out with compressed air, rinses them well in very hot water.
Re-assemble and repeat. They should look like brand new when you are done.
It is probably a $300 bill if you take it in and it is probably a 2 hr shop job for a trained mechanic.
Thanks. I did just do a full carb clean. With all new carb kits.
How is your spark? Have you tested it with a good spark checker? Bright and strong? Do the plugs look good? Pull ALL of them, not just one. If one or two look bad, we have a key clue to what’s going on.
Those Mercs were notorious coil-eaters. I’m wondering if one or more of your coils isn’t going bad? Even to the point where you may have dead cylinders because of no spark.
Grouse
They were a bit wet when pulled. But spark was very good on all 4.
When its running, it runs great. Nice smooth idal. It just smokes more than it should. Not sure if the oil injection is putting in to much to fast or . I do know i got old gas in the big built in tank that i should probably just drain out and replace
What oil are you running?
Yes! Get rid of the old gas.
How did you test the spark? Just eyeballing at the spark plug? Or did you use a tester with variable gap?
I still suspect coils.
And before somebody who knows nothing about oil injection systems suggests it, NO! Do NOT remove the oil injection system. And NO, your brother in law’s cousin’s best friend’s stepdad did not blow his engine because the injection system suddenly failed. You have a far better chance of getting hit in the pants zipper by lightning than you do having an OI system fail in such a way
Grouse
Eyeball it. I suppose ill get a tester for better results. But the spark was very good looking. But id like to have it all working properly so ill pic one up. Any certain tester i should get? Something from a auto store ?
So if a coil is going bad that would make the oil not burn all the way witch would make it smoke more is what your thinking?
My suggestion would be doing things in order.
1. Get rid of questionable fuel. A must.
2. What oil are you using? If not high-quality semi or full synthetic, either burn it and don’t refill until the tank is almost empty or pump it out and refill with high-quality oil. IMO fully synth or Penzoil’s Premium Plus semi is the only way to go when it comes to low smoke.
Engines can be very oil sensitive. The last big 2 stroker I had would smoke like a cheap cigar on anything of low grade.
3. Replace plugs if you haven’t done so within the past year.
4. With good fuel and oil, see if the problem goes away.
5. Get spark checker with an adjustable gap like this one.
The point of the adjustable gap. IMO, is it’s not just a yes/no light where a weak spark will still light the lamp. You see the spark and you can adjust the gap to “stretch out the spark” to see how far the spark jumps on one coil vs another coil. Key for figuring out if you have one bad coil.
Grouse
Thanks for the info. The boat is new to me so i dont know what oil it has in the tank so ill get some full synthetic and get new gas in it. And see what it does after that. Would Yhe quicksilver synthetic be a good oil?
Ill find a spark tester like that to test coils also once i get the rest going
Easy to check the oil injection. Open the throttle to WOT and make sure the oil injector linkage lines are lined up, same as looking at timing marks.
I’m not an expert but ive had 2 coils go out on me recently and neither time she smoked alot. Unburnt fuel will smoke but not considerably. Motor would run like crap at idle and running.
As stated, get good fuel and oil running thru er and go from there. The injection system is suspect if acts the same. Which also went out on mine (small perforation on oil gasket which leaked more into system than it should) and it smoked like a freaking coal train!
The boat is new to me so i dont know what oil it has in the tank so ill get some full synthetic and get new gas in it. And see what it does after that. Would Yhe quicksilver synthetic be a good oil?
Yes, that is the first place to start. Good gas and good oil.
No to Quicksilver FS. I have never liked that oil compared to other brands on the market. It’s better than El Cheapo special oil, but not by much. Get something else if you can.
Grouse
The other i seen locally was the Johnson oil. But i can look for something better if thats not the best either?
I usually get this at Walmart. TFG turned me on to it years ago. Good stuff.
Screenshot_20190820-162529_Chrome.jpg
depending on what oil you are using now even if its quicksilver oil it will smoke a bit on start up,its the nature of the beast.
only true smokeless formula two stroke oil will clean it up and it will take a tankful or two as it has to get the old dyno oil cleaned out.
I use to use Lucas land and sea two stroke oil but have since started using Schaffer extreme two stroke oil,very high quality stuff !!
if the smoke is excessive I would about bet that the 2PSI valve is either stuck open or the spring inside of it has broken,this is very common on mercury motors that were oil injected.
the 2PSI vavle is a pressure regulator hence its name,it opens at 2 PSI.
it is located in the line directly after the oil injection pump and is made out of brass.
it is a non serviceble valve and if bad will need to be replaced.
excessive oil being injected causing hard starting especially after sitting a while as it will allow oil to flood the carbs.
you are lucky if it has stuck open vs being stuck shut and not allowing oil to be injected at all.
to get it out,cut the two zip tyes on each end of it,pull the lines off of each end.
the ends are two different sizes so that you cant put it back in backwards.
to test it,spray some brake cleaner through it as if it was installed,in other words follow the direction of flow.
if you can see the solvent coming out one end while spraying in the other end its bad.
you can try using your mouth and blowing through it once its clean,you should have to force air through it,if you can get air through it with very little effort it is junk,esecially if you can blow through it from either end,dont try cleaning it and putting it back,replace it !!
they are not an expensive part.
if you find its bad and need help finding the right part PM me your model and serial number and I will find it for you.
once replaced,install two new zip tyes and go.
0D267943 is the serial number. Ill be checking it tomorrow. Im going to bet between that and the cheaper oil are my two issues
0D267943 is the serial number . Ill be checking it tomorrow. Im going to bet between that and the cheaper oil are my two issues
I usually get this at Walmart. TFG turned me on to it years ago. Good stuff.
A long time ago, back when most of us including the big offshore saltwater boys were still running 2 strokes, I asked the question on a saltwater forum: What it the lowest smoke, best quality 2 stroke oil for the price?
Overwhelmingly, the answer came back: Penzoil Premium Plus. And not by a small margin. Many of these guys had tried lots of oils, but a lot of them settled on the Penzoil.
You have to understand that in the midwest, it’s like boating kindergarten compared to the bluewater salt guys. Many gulf and east coast guys are putting on 10 hours for every 10 minutes your average midwest walleye guy puts on a boat in a season. A midwest walleye guy thinks he’s put on a lot of hours when he hits 100. There were guys out there that had 2000+ documented hours on 2 stroke engines and routinely were topping up their boats with hundreds of gallons of gas and gallons of oil just to run out for a weekend day of fishing.
I recall a guy in Florida that said he burned almost a case of oil for every trip out to the rigs in the gulf. A case being 8 gallons.
So I’ve been using it ever since. Works great, lowest smoking oil I’ve ever found for the price, and easy to get.
Grouse
You guys are awesome. Thanks so much
Ive got alot to do to figure it out now. I will update when i can to see how it all goes.
I really appreciate all the help! Id rather do my own work and learn along the way, and you guys make that possible!!
if you find its bad and need help finding the right part PM me your model and serial number and I will find it for you.
once replaced,install two new zip tyes and go.
Make sure you use the hose clamp style zip ties, NOT the common hardware store zip tie.
zip tiezip tiezip tie
When looking closely at the illustration, one can see that the base of the zip tie is “arched” to seal against a round hose.
here ya go, https://www.boats.net/product/mercury/8189941?gclid=EAIaIQobChMIrsux8t6S5AIVcRh9Ch2HRQehEAQYBCABEgI_iPD_BwE
Dave has a good idea on using the arched zip tyes,I will admit I have used the others before the arched ones came out for years without one single issue.
here ya go, https://www.boats.net/product/mercury/8189941?gclid=EAIaIQobChMIrsux8t6S5AIVcRh9Ch2HRQehEAQYBCABEgI_iPD_BwE
Dave has a good idea on using the arched zip tyes,I will admit I have used the others before the arched ones came out for years without one single issue.
I have too, in a pinch. 
The proper ones are the best choice for a hose application.
You must be logged in to reply to this topic.
