2000 Johnson 50hp 2stroke - oil leak questions!

First off, I would like to thank everyone for all your contributions to this forum. While this is my first post, I have been lurking around and getting great information just by searching through old threads which has really helped me get my "new" boat up and running.

Last year, I purchased a 2000 Princecraft 16" fishing boat with a oil injected 50hp Johnson 2 stroke (model year 2000 as well). I purchased it from the original owner who just never ended up using it after his fishing buddy passed away. Long story short, we have loved our new family fishing boat and spend almost every weekend on it. My 3 year old lil girl fishes with me for up to 5 hours without a complaint! Back to the question today...

1.) Since I have owned it, there will be a small amount of oil that will drip into the back part of the boat (sorry don't know the name but the top drain area in front of the transom). Its not much of anything but it always bugs me on where and why it is there. Everytime I wipe the braided nylon cover over some of lines going into the front of the motor it is dirty with oil so I am guessing there is a leak on the oil line that runs into the motor which has me concerned. Is this normal? Should I have it checked out or is this something that I can easily swap out a new oil line?

2.) We just got back from a vacation where we took the boat with us and it was the first time I used a transom saver since it is the first time we really traveled with the boat. It was a 1000 mile roundtrip. Got home yesterday and I just went out to onload and clean the boat. I noticed that there was some oil (black... looked like used automobile oil) dripping down the front of the lower unit and it was also on the transom saver. Again, not a huge amount but anytime I see oil where it is not suppose to be I get worried. It appears to be coming out of a small square hole that is just above the lower unit (I think I am calling it the correct thing - cast piece where I do the oil change and that has the prop/skeg/water intake/ect). It is in the front of the motor just between where the lower unit and the motor shaft (again sorry if I am not describing it correctly) meet. I checked the lower unit oil and it does not have water in it. What could this be and what is my best course to remedy without breaking the bank! Thanks in advance for your help!!!

Re: 2000 Johnson 50hp 2stroke - oil leak questions!

More than likely its all related.What happens is,when you tilt your eng.up,the carb bowls empty out through the front of the carbs.The large plastic carb cover ,should have a gasket,which ,always tends to break over time ,or the many bolts become loose ,or the plastic itself warps over the yrs from heat.Ideally,the gas is supposed to remain in the cover,wherby next time ,it goes out a drain on bottom of the cover ,inside there is a hole that a hose then connects to and the gas then goes into the crankcase next run.In a perfect world ,when new ,it might happen.What happens next is the gas finds any easy way to drain,it finds itself inside the midsection ,where it meets up with old grease ,oil and exhust,it mixes and the result is the crap that finds itself out any opening it can find.You can try fixing by taking the carb cover off,replacing the gasket after cleaning the mating surfaces,make sure the drain hole is clear,the hose is there and not cut,when you put the bolts back,snug them up evenly,surelt there is a torque spec .to insure the plastic isnt warped by over titening,I dont know the number but would guess its about 50 INCH pounds,just a guess.To clean the mess ,I use GUNK ,the foam type.It relly does a good job.Find an area other than your nice clean painted driveway,or any surface you dont want permanent grease stains on ,spray it on the bad areas ,let it sit for 15 - 30 min,then hose off.Go over it with a good soapy spray,I use dish soap in a spray bottle diluted about 50% water, and re rinse ,with hose

Re: 2000 Johnson 50hp 2stroke - oil leak questions!

Thanks for the quick response. I just uploaded some photos and thought I would add them to the thread for a better visual of what I am talking about (since I am not sure I am calling everything by the correct name). Hope these help:

Re: 2000 Johnson 50hp 2stroke - oil leak questions!

man that eng is pretty for 10 yrs old,yep,Im sticking to what I said,BUT,check under the hood for any possible gas leaks,I really expected to see a big ol mess.Frankly ,your nice and clean,I dont think you can expect it to be spotless .I see nothing to alarm about

Re: 2000 Johnson 50hp 2stroke - oil leak questions!

Thanks. I got a great deal on the boat as it was used very little (estimated only 40 hours on the engine from previous owner) and I try to take care of all our "investments". As you will see in the images below, the motor is very clean inside and out. I do not see gas or oil under the cover or in the bottom of the opening. The only place I saw some oil inside the cover was around the rubber grommets where the controls and tubes enter the hood (1st image) but there was maybe 3 drops worth in each area when I just wiped it clean. The rest is pretty clean as shown below.

Like I stated previously, there has always been a very tiny amount of oil that leaves it mark in the back transom area from that braided nylon tubing (do not know if that is where it comes from but the nylon at least collects it and then drips small traces in that top transom area). The black oil that appeared between the lower unit and the shaft (pictured previously) just showed up since I loaded the boat for our trip back home yesterday. If I wiped up all that was present, I would say that it was about 1/4 -1/2 oz of oil. Again, this has never been there in the previous 18 months that I have owned the boat. Not trying to be too picky here, just want to make sure I take care of my investment and do not do any damage to the motor by running it while something may be in need of repair. Let me know if there is another picture that you need to help diagnose where this is coming from (leak above lower unit is most concerning). Thank!!!

Re: 2000 Johnson 50hp 2stroke - oil leak questions!

Re: 2000 Johnson 50hp 2stroke - oil leak questions!

The more I look at the point where the oil appeared today just above the lower unit, the more questions I have. In these images, is there suppose to be something (rubber plug?) in that square hole. Also, is that line (light gray from where paint has flaked away in top image) on the lower unit suppose to be there that travels down or is that a crack or split in the weld? I do not see any other split like that in the lower unit housing.





Here is the parts manual photo and there is not visible seam on that part of lower unit (gearcase).

Re: 2000 Johnson 50hp 2stroke - oil leak questions!

Just a couple words of advice for you. First put it in the water and go 2nd you will drive your self nuts being so anal.

the little bit of oil or gas is very little
the seam in the lower unit is ok and not to worry about.

Boats are maintenance magnets but they will also let you know when there not feeling well. Just listen