Automotive synthetic oil

[termigator]

Has anybody used automotive motor oil (specifically synthetic) in their outboard? I have a Mercury 4-stroke 25 hp outboard and I normally change the oil once a year with Quicksilver 10w30 (as recommended), but it's hard not to notice all of the clearance oils going on at WM. I especially noticed a qt. of Quaker State Ultimate Durability 10w30 on clearance at $2.50 and I was wondering if it would be o.k. to mix that with a qt. of Quicksilver (my outboard calls for 2 qts. of oil). FWIW, the motor is no longer under warranty.

 

[bepperb]

Do you use it in saltwater? The advantages of the marine oil are better water emulsion and corrosion resistance. If you were here where there is only freshwater a non-energy conserving 10-30 or better yet an HDEO 10-30 would probably be fine.

 

[Doog]

Not in salt water. Stick with the Quicksilver. I have used it for 30 years and never had an issue.

 

[NMP]

I also have a Mercury 4 stroke. As far as oil goes, what did you pay for a quart of Mercury's oil? Multiply that times the number of quarts to change. Now divide that number by the cost of the motor. What you get is a number that's in the tenths of 1 percent of the cost of the motor.

Save money by drinking cheaper beer ;-)

 

[Tuffy1760]

For just 2 Quarts, I'd look at Amsoil marine or RP marine. A few bucks difference for a high dollar motor... new about 3K??

 

[OVERKILL]

Does the manual list a spec that the oil must conform to?

 

[RTexasF]

Originally Posted By: Doog
Not in salt water. Stick with the Quicksilver. I have used it for 30 years and never had an issue.


Merc hasn't had four strokes for thirty years but I agree it's a good oil. For the minor cost difference I would stick with it.

 

[hattaresguy]

Any 10w30 will be fine.

Around here Pennzoil is popular.

Quicksilver is a great oil but its nothing special.