Honda smoke after oil change

rxl650

Petty Officer 3rd Class
Joined
Jul 19, 2020
Messages
90
So it's an old 1995 bf50 and new to me. Has not smoked before today. I changed the oil and filter according to the owners manual and supplies from my local marina. Before I started the motor I had it tilted all the way up to service the prop and shaft. I lowered it back down, put the muffs on and when it fired up there was an instant cloud of blue smoke. I was going to run it for a few seconds to get the oil to the filter and then top it off.

I wondered if having the motor at full tilt during the oil change could have anything to do with this condition. It ran for about 4 seconds and I came right to you folks before I try restarting it. Old guy who loves his ol' smokers. Sleds included. I havent even had this boat on the lake yet and we're off to bad start. lol

I appreciate any input. Thanks to all.
 

MattFL

Master Chief Petty Officer
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Oct 20, 2010
Messages
866
If it's not smoking constantly and not using oil I would not worry. I suspect the fact that it smoked after an oil change is just a coincidence. Just to give you another data point; I've got a 1999 50HP Honda and randomly it will give several seconds of blue smoke on the first start of the day, but it clears quickly and doesn't repeat until it sits unused for some time (days), and does not smoke during use. I haven't been able to figure out the pattern, but it does it a few times a year and has been doing it on and off for the last 10 years or so (I bought it new in 1999). It seems to happen more often when it sits for a week or two without use. Other than that it runs great and doesn't use or leak oil so I'm not worried about it.
 

rxl650

Petty Officer 3rd Class
Joined
Jul 19, 2020
Messages
90
Thankyou for ease of mind.
I just went out and topped the oil off, turned the key and it was like it never happened.
I notice a little cough when it's cold and I give it a quick shot of throttle. How long do these take to warm up? My 2 strokers are ready to in about 30 seconds as soon as they will run without choke. After a full minute this thing will still pick up rpms when I blip the manual choke. Takes a few minutes for the rpms to get steady.
Fluids are all done, prop and shaft are greased up, fuel line replaced, filter was clean, fuel is clear and plugs look good. Forgot to grab some new ones this morning.
I had to get something besides my side console for the wifes comfort. Picked up a Sylvan 1600 explorer dual console that spent it's life in a boathouse. Seems to be in pretty fair shape. Carpets are like new and no sign of rot anywhere.
Nice night to head out and water test.
 

MattFL

Master Chief Petty Officer
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Oct 20, 2010
Messages
866
As mine got older it became increasingly difficult to keep a stable idle. It either wanted to race or stall. After a long full throttle run when it was really hot the idle would be too high, but as it cooled down the idle would be too low sometimes even stalling. Replacing the fuel screws with the non-EPA screws pretty much cured it, I was then able to tune it to where it actually runs good. Prior to the change it would definitely need the choke and a little throttle when cold, and I would sometimes have to bump the choke a few times to keep it going until it built up enough heat to idle. With it properly tuned with the new fuel screws sometimes I don't even need the choke on a cold start, at most one bump to get it started then it idles immediately. I don't know if your motor is the same as mine, but I attached a picture showing the EPA screws with the heads broken off and one still attached to the screw remover that I used to take them out. The part# on the bag is for the replacement screws. Double check that yours is the same as the 1999, but if it is then this is what you will need. If it doesn't idle well, make sure the carburetors are super clean (spray cleaner and air through every hole, wear goggles!) and the carburetors are sync'd.
 

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rxl650

Petty Officer 3rd Class
Joined
Jul 19, 2020
Messages
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I seen that picture in another thread I was reading. On my list of things to do. We got out for the first run last night. It's actually an Adventurer model, not the Explorer.
It idles perfectly under load and performs well but I noticed a rattle at high rpms. I'm hoping it's just a ping as the boat was already winterized with twice the stabilizer called for. I also have no idea as to the conditionof the fuel in the inboard tank. It looks clear and the filter had no signs of contamination.
I'm to busy with work in the fall to let myself get distracted, but it seems like I need to start by draining the tank and maybe a manual for valve adjustment. Or maybe start with new plugs. lol.
Most likely a spring thing. I still have my side console for spring salmon fishing so I'm in no rush. My wife doesnt like freezing morning temps and breaking ice to fish anyway. lol
 

ahicks

Captain
Joined
Sep 16, 2013
Messages
3,957
A little puff of blue smoke on occasion not unusual in my experience either. Some of the stuff I work on will have been sitting unattended for several years - and there's no pattern with them either. Sometimes you see a puff, sometimes you don't!

The little cough you hear on a cold motor is generally one of the carbs that's either set a little lean on the idle mixture screw, it's telling you it's time to clean it - again, or it may be time to check the carb synchronization. If one of the carbs isn't pulling it's fair share, that cough could be telling you that carb/cylinder is cutting in and out because there's no load on it. That the others are doing all the work when on idle.

I would check the mixture, then clean the carbs, then drag out the vacuum gauges..... -Al
 

MattFL

Master Chief Petty Officer
Joined
Oct 20, 2010
Messages
866
Mine has never made any rattling noises from under the hood, that doesn't sound normal, but check around as it is likely something vibrating, or bad fuel. The steering bar on the front of the motor can vibrate and make some noise, is that what you're hearing maybe?
 
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