USA_boater
Petty Officer 1st Class
- Joined
- Jul 31, 2018
- Messages
- 275
I am asking about a 2018 50hp but in general I'm sure others may want to know the answer and the caveats to their particular outboard.
If they are like I think they are, I am wondering why the OEM oil is "catalyst compatible" if many of their motors do not have a catalytic converter. Low valve spring pressures perhaps? I would think for longevity that they would have a catalyst and non-catalyst oil available just like the aftermarket does (sierra, west marine, etc.)?
Running 6k RPM on a non-roller motor with an SM or SN rated oil doesn't seem like the optimal thing to do. Can anyone explain the logic other than "don't question the Mercury engineers"...I think there are most certainly other influences on the OEM oil offerings & engine designs than just the engineers.
If they are like I think they are, I am wondering why the OEM oil is "catalyst compatible" if many of their motors do not have a catalytic converter. Low valve spring pressures perhaps? I would think for longevity that they would have a catalyst and non-catalyst oil available just like the aftermarket does (sierra, west marine, etc.)?
Running 6k RPM on a non-roller motor with an SM or SN rated oil doesn't seem like the optimal thing to do. Can anyone explain the logic other than "don't question the Mercury engineers"...I think there are most certainly other influences on the OEM oil offerings & engine designs than just the engineers.