4 strokes and synthetic oil

[Dan180cc]

I am looking for some advice on using synthedic oil in a 4 stroke outboard. I have a Johnson 140 2003 which is coming up on its first oil change.<br />I have never changed oil in an outboard before only auto,s. Is there anything different that I should know about?<br /><br /> I am considering Mobile 1 synthedic oil, I have read about its advantages in auto's but I dont want to get into any trouble with the Johnson if I use it. The manual I got with the motor does not tell you much as they call it a dealer service routine.<br /><br /> I have to get the filter for them. SHould I just let them do it? Thanks Dan.

 

[Dan180cc]

Re: 4 strokes and synthetic oil

Should have put this in outboard questions.Sorry

 

[sony2001]

Re: 4 strokes and synthetic oil

My conclusions from previous chats on this is that syn is great but not to be used for storage. Inside rusts. So a foolproof way may be to go with syn blend.

 

[JB]

Re: 4 strokes and synthetic oil

One of the advantages of Mobil 1 is that change periods may be extended, but you need a ECM that monitors engine oil temp and usage to determine when to change. My ML320 does that and because of my extended highway usage it sometimes runs the oil over 10K miles before changing. It does require 100% synthetic.<br /><br />In our 4 stroke outboards we change oil at 100 hours regardless of usage. Suzuki (who also made your Johnny) says Mobil 1 is fine in my DF70, but I must change it on schedule. My dealer says it is a waste of money.<br /><br />I haven't heard anything about internal rusting due to synthetic oil.<br /><br />I use Mobil 1 in all my 4 stroke machines because I trust it. I have had no oil related problems. I recommend it if you can live with the extra expense. <br /><br />Moving this to Outboards.