2003 yamamerc 225 4stk.

[ricwing]

this motor has 300 hrs on it and have used yammy 10W-30,would it hurt to change to a auto syn.oil aka MOBIL 1,or just stay with yammy oil,i change oil every 50 hrs and filter every 100 hrs. because a troll alot and bottom fish and never turn engine off. Would there be a benefit changing.

 

[hamit59]

Re: 2003 yamamerc 225 4stk.

Hi,
Merc book says to use 10-30 or 25-40. I'll ask you how cold is the water you run in? you can run any oil you want too. But if the water is cold, it's better to run a 25-40 oil. As merc told me cold water splashing on the crank case.will keep the oil cooler than in an auto.If you were to be skiing all day long with hi speed and hi loads then 10-30 might work fine. I'm like, you I troll a lot. My oil temp might get to 130 f . I choose to stay with the 25-40 lower oil temp means I'm still oiling my motor with 25 weight oil At trolling speed. When I do open it up I have good 40 weight oil at hi oil temps

This is my 2 cent worth the choose is yours

 

[ricwing]

Re: 2003 yamamerc 225 4stk.

i am in the fl.panhandle so cold is not an issue, but anyone use the mobil 1 synthetic oil in their 4stk. outboards?

 

[hamit59]

Re: 2003 yamamerc 225 4stk.

As I said before can use any oil you like.
This is what the book has to say

SAE 10W-30 or 10W-40 viscosity oil is
recommended for use in all temperatures.
SAE 25W-40 viscosity oil may be used
at temperatures above 4? C (40? F).
Use 4-Cycle Marine Oil with the proper
viscosity for the expected temperature
in your area If not available, use a premium
quality 4-cycle engine oil certified to
meet or exceed any one of the following
American Petroleum Institute (API)
service classifications SJ, SH, SG, SF,
SE.


I hope this answers your Questions

 

[twostroke87]

Re: 2003 yamamerc 225 4stk.

The only difference between the auto oils and marine oils, is that the marine oils have anti-corrosion additives that will protect your internal engine components leading to a longer engine life. Its not that the automotive oil will hurt it, it will work just fine, but later down the line you might wish that you had stuck with the marine oils.

If you are in florida you have a very high amount of salt in that water, and corrosion should be on your mind, I know that the internal components of your engine shouldn't ever directly contact the water (hopefully). But If they do, say bad head gasket, the marine oil will protect it better until you replace the problem.

Even if you don't lose your head gasket or anything like that, your engine is still aluminum, and although the block doesn't directly contact the water, it is connected to the lower unit, which is always under attack by electrolosis. So your block is somewhat affected by corrosion internally and externally to an extent.

 

[yamamarinetech40]

Re: 2003 yamamerc 225 4stk.

Yamaha does not(asked in class) at this time say it is ok to use synthetic oils in ANY of their engines, I suspect due to sealing problems, but couldn't get a real answer on it. Why would you want to? The engines last forever on Yamalube(Navy has put OVER 8500 hrs on som F150's) so why? Just curious.