Engine oil???
 

I can't find what type of oil my Mariah shabah Z250 with a 454 takes. I think maybe 15w40. Please let me know if this is right?????:confused:

Re: Engine oil???
 

Mercruiser recommends their Quicksilver 4 Cycle oil. Which is a 25w40. However if you use their oil, you'll soon find your wallet quite a bit lighter... It's roughly about $9/quart.

Most people I know, (including myself) run a 4-cycle 15w40 oil, such as West Marine Premium, Rotella, Pennzoil, etc. It's essentially the same stuff as the Quicksilver, has never caused any oil related issues at all, and it's a bit cheaper on the pocketbook.

Re: Engine oil???
 

i always use castrol 10w40 for my 350 available at wal-mart or any parts store. has worked for me for years without fail....

Re: Engine oil???
 

10w 40 in the MPI 7.4. Total of 475 hrs and been running it since around 300. No problems. Its the mobil 1 from walmart- 25$ per 5 quart jug is a hard price to beat...

Re: Engine oil???
 

I run the rotella. It's additives are formulated for high load applications. (Ie diesel engines) I have full confidence in it protecting my engine. And it's relatively inexpensive. Oil filter and fuel/water separator are available at Napa.