Changing Oil In 4 Stroke Yamaha

Discussion in 'Bubba's Outboards' started by Gordhawk, Apr 29, 2007.

  1. Gordhawk

    Gordhawk New Member

    Messages:
    1,378
    State:
    Iowa
    I have a 40 HP 4 stroke,and I was wondering if I have to use a motor oil specifically made for 4 stroke engines. In my owner's manual,under recommended engine oil it says 4 stroke motor oil,and then right below that it says API SE,SF,SG,SH 10W30,10W40,20W40. I'm confused,does that mean that I can just use a good 10W30 oil like Castrol GTX or do I have to go buy Yamaha 4 stroke motor oil? Can anyone please help me with this?
    Thanks,
    Glenn
     
  2. jbarnes17

    jbarnes17 New Member

    Messages:
    536
    State:
    Commerce, Oklahoma
    Glenn, I have a 18 hp tohatsu 4 stroke and I wondered the same thing myself. It is almost time for me to change the oil as well. I would think any brand would do. Hopefully, someone can give us an answer.
     

  3. Bobpaul

    Bobpaul New Member

    Messages:
    3,039
    State:
    Supply NC
    Use any good quality oil with at least those API grades , or better.
     
  4. Gordhawk

    Gordhawk New Member

    Messages:
    1,378
    State:
    Iowa
    Bob,
    I take that to mean that the Castrol GTX 10W30 that I referred to will be alright to use,right? All 4 of those S codes don't have to be on the container of oil do they? There are 4 of those S codes on the quart containers that I bought,but only 1 of the 4 is one that was listed in my owners manual.
    Thanks Bob,
    Glenn
     
  5. Mr.T

    Mr.T Active Member

    Messages:
    2,554
    State:
    MO
    I use Yamalube 4M in my 115, mostly because I don't know if there's anything special in Yamaha oil or not but I'd rather use the factory-recommended stuff than find the cheapest quart at Wally-World.

    I've also been running Yamaha Ring-Free in the fuel since the first day I owned the engine. At 1oz per gallon of fuel, it's well worth the expense as far as I'm concerned.

    There are online sources for Yamaha oil that are far below the retail price at your local marine dealer/shop.
     
  6. metalman

    metalman Well-Known Member

    Messages:
    3,457
    State:
    IN
    Name:
    Winston
    Glenn,
    Not to nay-say what the other guys have told you but is your motor still under warranty. If so, use the Yamalube. I have an F115 and in the warranty part of the manual it is very specifically worded that if you don't use a certified marine grade 4 stroke oil your warranty is void as far as any internal engine issues go. The wording in the warranty actually contradicts the wording in the maintenance part of the manual which says what you referred to. Yamaha are notoriously bad when it comes to warranty issues in that they seem to try everything to get out of things being their responsibility. Having said that I would bet that a very high percentage of motor problems are owner induced...W
     
  7. riddleofsteel

    riddleofsteel New Member

    Messages:
    353
    State:
    NC
    Under warranty use what the book calls for.

    I was told by my dealer to use regular motor oil of the proper grade in my Honda 4 stroke until I get a few more hours on it. Then I could switch out synthetic if I wanted to. I don't really know why but it may be related to seating rings ect.
     
  8. Mr.T

    Mr.T Active Member

    Messages:
    2,554
    State:
    MO
    OOPS..

    My mistake -- the correct ratio for Ring Free additive is 1 oz per TEN gallons of fuel - and a quart of the stuff lasts you forever.
     
  9. Gordhawk

    Gordhawk New Member

    Messages:
    1,378
    State:
    Iowa
    I forgot to mention that this motor is a 2000 so it is no longer under warranty. I guess I didn't phrase my question very well,because it's not about the cost of buying the Yamaha oil, because that's what I been using since I got the motor 3 yrs. ago. I just wanted to know if you had to use the Yamaha 4 stroke oil,or could I just use a good name brand oil. BTW, I don't consider Castrol GTX oil to be the cheapest on the shelves at Wally World!!
     
  10. Bobpaul

    Bobpaul New Member

    Messages:
    3,039
    State:
    Supply NC
    Again, an oil with the API service codes is acceptable and does not void warranty.

    But ya'll do what you want, you will anyway!
     
  11. JAYNC

    JAYNC Active Member

    Messages:
    1,312
    State:
    Newport N.C.
    Just find an oil that is NMMA certified, I used the regular mercury oil that it came with for the break in period and then another 25hr on regular oil. Then I switched to the mercury synthetic blend, which was recommended by the master mechanic at the dealer, I also use ring free that stuff workd great. Its amazing, just before you change your oil look at the dipstick and it might be a little dirty and then do the shock treat for one tank of gas just before you change your oil. When you drain your oil you will see that its the blackest oil you have ever seen, and thats because the ring free cleans your engine out real nice. you can use mercury oil because my engine is a mercury brand but the whole powerhead is a yamaha. I wouldn't use an oil that is recommended for cars, cars dont run at 4-6k rpms all day, and the NMMA only certifies oil that can withstand that abuse.