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  1. #1
    Join Date
    Oct 2017
    Location
    London, England.
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    Question Newbie seeking help with Japanese Mariner

    As I can imagine a lot of first posts are for seeking help, I'm unfortunately going to be no different.

    Very long story short, my neighbour left this beautiful thing abandoned in his backyard for 6 months. I spoke to the landlord and he said I may take any of the obviously neglected items from behind there, and this is where my story starts.

    Introducing the Hydra-ski! https://imgur.com/60jeAf1

    A bit of background from me: Many many many moons ago my Dad used to own a house on a lake in South Africa and we had a speed-boat with a 200hp Mariner on it. It was a beaut. I was about 8-10years old at the time, so I don't remember too much, but it was the start of me loving boats and outboards. Fastforward to now, I'm 25years old, I'm a software developer, and my main hobby is golf. So, far from anything that actually requires the use of my hands. However, I'm not shy of a challenge.

    So I got the boat in my driveway, gave it a scrub, and now I've got this: https://imgur.com/uBpZlk0

    Boat wise, I'm not too fussed as I've figured most of it out without hassle.

    Outboard wise, I'm at the mercy of you guys.

    What I know so far: It's a 1980'ish Japanese made Mariner. 2 stroke, 20hp. Exhaust comes through the prop. Googling '6a9 outboard' seems to give the nearest results to it, but no direct matches. Here's the only label on it: https://imgur.com/sUtOxXU

    I'm trying to get this motor to run because my ultimate goal is to actually take this out on the water. I've never seen anything like it and wouldn't want to just hand it off to someone to let them have all the fun.

    What I've done so far (Please note that 99% of my knowledge comes from either reading about it online or YouTube):

    * Check the stator's resistance (resistance seems near to similar engines, but can't find manual for exact reading)
    * Made sure the kill switch was working as intended so that it wasn't shorting out the ability to start the motor
    * Cleared out the fuel filter
    * Cleaned the carburetor to the best of my ability with carb cleaner
    * Got a new fuel line, fuel tank, and hooked it all up
    * Replaced the gear case lubricant
    * Bought marine grease and greased what I best found I should

    Once I spent about a good two days of researching, watching online, and fiddling, I got it to start... using carburetor starter spray. I went back to checking fuel filters and such and realised I could've done a better job as I had the dark tea colour fuel. Once I cleaned it again, I got it to start and run under its own power (with muffs on, of course), for about 30 seconds. During that time I observed a milky, and oily to the touch, liquid coming out the prop area. It was a reasonable amount of liquid coming out and it was quite consistent. From this I then read up that it's possibly because I'm getting water in the oil and it's causing it.

    So here's what I'd like to ask:

    1 - Is water in the oil/fuel mixture the result of water getting in there, and does this mean I should replace seals? (I'd have no idea which ones to target)
    2 - Could anyone recommend a place to query about a motors manual this old? I've love to be able to test the cylinder pressure or maybe replace the carb (but I've got no idea of fuel spray rate that it would require).
    3 - Any advice for things I should check/learn about?
    4 - What should I name 'it'?!


    Many thanks!

    *Edit - Here's any/all photos I have of the project so far: https://imgur.com/a/OznkK
    Last edited by Mennace; 10-11-2017 at 11:30 AM.
    I work in IT, have you tried turning it off and on again?

  2. #2
    Join Date
    Dec 2015
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    maplevalley WA
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    Default Re: Newbie seeking help with Japanese Mariner

    Does it smell like gear oil or fuel? If the gear oil is not milky and the engine runs good take it out for a romp. It could be old oil in the exhaust housing running at high RPM will blow the cobwebs out. Use the serial number for looking up parts it is the bottom number just find the range it fits inbetween. Thats alot of motor for that boat be careful it should fly.
    It takes a nickle to go first class!
    If it aint broke dont fix it!!

  3. #3
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    Oct 2017
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    Default Re: Newbie seeking help with Japanese Mariner

    Quote Originally Posted by kimcrwbr1 View Post
    Does it smell like gear oil or fuel?
    No, I can't say it had a distinct smell that I could smell. I might need to spin it up again to see specifically if it does and catch a sample in a cup.

    Quote Originally Posted by kimcrwbr1 View Post
    It could be old oil in the exhaust housing running at high RPM will blow the cobwebs out.
    When I said I got it running for 30 seconds, I should've probably mentioned that it's the longest I got out of it. It unfortunately doesn't sustain itself under it's own power entirely just yet

    Quote Originally Posted by kimcrwbr1 View Post
    Thats alot of motor for that boat be careful it should fly.
    ...and can you believe the hull actually has instructions on it that say the max engine that should be on it is 30hp?! I mean, I'm a little silly but I'm not toying with that deathwish.
    I work in IT, have you tried turning it off and on again?

  4. #4
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    maplevalley WA
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    Default Re: Newbie seeking help with Japanese Mariner

    Spunds like it needs a good once over. First off do a compression test before spending any money. If the compression numbers are good pull the carb and put in a kit #84773M. Take it completely apart except the butterfly and soak it overnight in carb cleaner. Blast the circuits good with high pressure water and blow dry with air. Do not put finger pressure on the float to adjust it pull it out and bend the tab then check it upside down the float should be level with the carb. preadjust the slow needle 1 1/2 turns out from lightly seated. It is a good idea to replace the fuel lines in the motor at the same time. Clean the fuel pump and if the diaphrams are stiff install new ones. I could not find a kit for the fuel pump you will need to do it piecemeal.
    It takes a nickle to go first class!
    If it aint broke dont fix it!!

  5. #5
    Join Date
    May 2007
    Location
    Ireland,the only country in the world you can go North to go South
    Posts
    1,837

    Default Re: Newbie seeking help with Japanese Mariner

    You have a 1985 Yamaha Mariner Manual start, Short shaft.And $30 would be money well spent on a manual.marineengine.com do ship manuals overseas. http://www.marineengine.com/manuals/seloc/mariner.html . Lovely wee don't know what to call it,should be hell of a lot of fun.
    Go easy on the starter fluid,no oil in it

  6. #6
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    Oct 2017
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    London, England.
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    Default Re: Newbie seeking help with Japanese Mariner

    Quote Originally Posted by haventaclue View Post
    You have a 1985 Yamaha Mariner Manual start, Short shaft.And $30 would be money well spent on a manual.marineengine.com do ship manuals overseas.
    Thanks for this, I'll be putting an order in ASAP

    Quote Originally Posted by kimcrwbr1 View Post
    Spunds like it needs a good once over. First off do a compression test before spending any money. If the compression numbers are good pull the carb and put in a kit #84773M.
    I've asked a few friends and I will be able to lend one from a friend at the start of next week. I'll let you know how it goes!

    Quote Originally Posted by kimcrwbr1 View Post
    Blast the circuits good with high pressure water and blow dry with air.
    Do you mean literally spray down the engine with clean water? My grade 5 science is telling me water + electricity = bad. Do outboards negate this general rule?
    I work in IT, have you tried turning it off and on again?

  7. #7
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    Dec 2015
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    maplevalley WA
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    Default Re: Newbie seeking help with Japanese Mariner

    When you rebuild the carb blast it after you soak it in carb cleaner the water scours the circuits good and then blow all the water out and put it back together. Yea I do spray a engine with the hose after giving it a coat of degreaser then start it up so it dries out good. Just be careful to avoid getting water under the flywheel. Be sure and shoot some grease in all the zerts marine grade grease at least once a year. It is also a good idea to take electrical connectors apart and clean with electrical cleaner then put some dielectric grease on them when you put them together to protect from moisture.
    It takes a nickle to go first class!
    If it aint broke dont fix it!!

  8. #8
    Join Date
    Aug 2017
    Location
    South Africa
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    Default Re: Newbie seeking help with Japanese Mariner

    Nice little boat! What lake in South Africa are you talking about?

    Anyway I have the Yamaha version of this motor and it is a pretty straight forward engine ..... firstly did you mix the fuel with 2-stroke oil ratio 50:1?
    Did you check the gearbox oil in the lower unit? The only ever problems these motor have is carb related, if you clean the carb perfectly (consider giving it a ultrasonic bath) it wil run first time every time.

  9. #9
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    Oct 2017
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    Default Re: Newbie seeking help with Japanese Mariner

    Quote Originally Posted by deejaycee_2000 View Post
    Nice little boat! What lake in South Africa are you talking about?
    I should've actually said dam, not lake! Regardless, it was Kwaggaskloof Dam, right next to Worcester in the Western Cape

    Quote Originally Posted by deejaycee_2000 View Post
    Anyway I have the Yamaha version of this motor and it is a pretty straight forward engine ..... firstly did you mix the fuel with 2-stroke oil ratio 50:1? Did you check the gearbox oil in the lower unit? The only ever problems these motor have is carb related, if you clean the carb perfectly (consider giving it a ultrasonic bath) it wil run first time every time.
    Yip, I mixed the oil in that ratio and I bought new gearbox oil to replace the stuff that was in there.

    At the moment my list of 'to-do' includes:
    * Clean the carb again (I think I did a pretty weak job the first time round)
    * Get a pressure test on the cylinders and then go from there
    I work in IT, have you tried turning it off and on again?

  10. #10
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    Aug 2017
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    South Africa
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    Default Re: Newbie seeking help with Japanese Mariner

    Oh yes, I spent alot of time at Kwaggaskloof as I grew up in Worcester!

    These little motors are great, the carb is pretty much the only thing keeping it from running right, I only ever changed 1 coil ever on mine.
    Best way to clean the carb (if you do not have or know someone that have a ultrasonic bath) is to disassemble it and soak it in carb cleaner over night and then blow out with compressed air. Make sure the jets are open and clean. The air/fuel mix screw should be set at 1 & 1/2 turns outwards from soft stop and then slight adjustment from there until it is perfect.

  11. #11
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    Oct 2017
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    Default Re: Newbie seeking help with Japanese Mariner

    Quote Originally Posted by deejaycee_2000 View Post
    Oh yes, I spent alot of time at Kwaggaskloof as I grew up in Worcester!
    Just because I know how small this world really is, I'll take the gamble and ask if you know anyone by the surname of Krouwkam (family friends of ours that run a attorneys practise down there to this day) or if you were around the ski club in the time I was there (this was near the 2000's), then hopefully Herman Fick might be a name that rings a bell to you (My Dad)

    Quote Originally Posted by deejaycee_2000 View Post
    The air/fuel mix screw should be set at 1 & 1/2 turns outwards from soft stop and then slight adjustment from there until it is perfect.
    Between the next two photos, could you possibly tell me which the air/fuel mixture screw is?

    https://i.imgur.com/4EDDPKP.jpg
    https://i.imgur.com/XcgjN64.jpg

    Greatly appreciate the advice!
    I work in IT, have you tried turning it off and on again?

  12. #12
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    South Africa
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    Default Re: Newbie seeking help with Japanese Mariner

    Yes I know the Krouwkam - I also use to be around there that time. Herman Fick does ring a bell but it is a long time ago haha.

    Click image for larger version. 

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  13. #13
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    Oct 2017
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    Default Re: Newbie seeking help with Japanese Mariner

    It's finally time for an update!

    Firstly thanks to kimcrwbr1 for the advice and the part numbers. I ordered a cylinder compression test kit as well as the carb kit. I replaced all the parts from the kit onto the card and I'm pretty sure it cleared up a lot of the fuel issues I was having.

    The compression test showed the following results:

    Top cylinder: https://i.imgur.com/brhJmrK.jpg
    Bot cylinder: https://i.imgur.com/3EmZkZR.jpg

    As best I could read, they're sitting at 90 and 95 psi. Now, since I don't have the service manual I can't figure out if that's right. One website says anything below 100psi is garbage while other members on the forum have said they've gotten below 50psi and it still runs fine. Bearing in mind that the pressures are equal enough, in 4 degrees C of weather, I think I'm happy with that.

    Now moving on to thank deejaycee_2000 for his advice. I was paranoid about my fuel mixture and his comment just made me chuck my last batch of fuel and redo it, just in case. Again, making sure that it's less likely to be a fuel issue. It also prompted me to clean out the fuel filter. I ended up taking the bowl out, pouring out the fuel in it, and then putting it back together.

    Where we're at now with the help of the forum:

    First and foremost, I got it running. Without fuel started. I'm adding in the full stops here for dramatic effect as it was such a huge moment for me in my journey of learning how this all fits together.

    I tried a few more times, and this is how it would run: https://www.youtube.com/watch?v=zXB8ny1o99U

    So as you can see, 10 seconds, it starves of fuel, and then dies.

    That was earlier in the afternoon and by the evening I could get it running indefinitely with the following trick:

    1 - Close the choke and pull two/three times.
    2 - Open the choke and pull, it would start by the second pull.
    3 - After 5-10 seconds (when it sounds like it's thinning out), close the choke 2/3rds or 4/5ths of the way until it responds again.

    Once I was fiddling the choke while it was running it seemed to be okay and could run as long as I was doing it.

    I've tried going to the internet to try and figure this out myself but the utter spread of information is immense and I don't know where to start.

    ...so once more I come to the marineengine forum and kindly ask, if someone could either tell me what I need to adjust to get this fixed or where I could go and look to find out myself it would be greatly appreciated.

    Once again, thanks to everyone that's helped me thus far.
    I work in IT, have you tried turning it off and on again?

  14. #14
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    Default Re: Newbie seeking help with Japanese Mariner

    Sounds good.Check your fuel pump diaphragm.
    Did you blow compressed air through the carbs? It only takes a small grain to create a problem.

  15. #15
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    Default Re: Newbie seeking help with Japanese Mariner

    Quote Originally Posted by haventaclue View Post
    Sounds good.Check your fuel pump diaphragm.
    I did, there were no tears or obvious deformities, so I put it back as it was. My only concern was that the gasket seemed a little worn and should be replaced (I've already got the part on order).

    Quote Originally Posted by haventaclue View Post
    Did you blow compressed air through the carbs? It only takes a small grain to create a problem.
    As obvious as this step sounds, I didn't unfortunately. Guess it's time to take it off again just in case and blow it out!
    I work in IT, have you tried turning it off and on again?

  16. #16
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    Location
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    Default Re: Newbie seeking help with Japanese Mariner

    The compression is good for that age motor, your readings suggest you have about 300 od hours on the motor, and will still be good for many years if you take care of it.

    From what I hear from your youtube video .... your carb is not quite there yet, you need to make sure all the jets are open, float hight needs to be perfect and air/fuel mix adjusted correctly.

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