25w-40 synthetic blend merc oil...work in cold?

[simplystressed]

I have a 50hp merc 4 stroke and am currently running the Merc Outboard 25w40 synthetic blend oil. I've heard that regular 25w40 oil isn't recommended to use when its colder than 4c. I'm not sure if being synthetic helps with the temperature range.

Reason being might want to go on one last trip this year and its around -2c right now. If I warm it up for a while before going fast should it be ok?

 

[JB]

Re: 25w-40 synthetic blend merc oil...work in cold?

Use for what??

 

[simplystressed]

Re: 25w-40 synthetic blend merc oil...work in cold?

Running in colder temps merc 50hp 4 stroke

 

[Silvertip]

Re: 25w-40 synthetic blend merc oil...work in cold?

See how important that little bit of information was (4-stroke). We could have assumed that but you would not believe the things people ask about thinking it is a reasonable question. I was checking out of Home Depot one day and the dude ahead of me had a new Lawn Boy two-stroke mower and one quart of regular engine oil. I decided to have some fun and congratulated him on his purchase. Good choice I said. I then added do you have oil for this mower? Yup was the reply - right here. Did you know you bought a two-stroke mower? Yes! Do you know you need to MIX the oil with the gas in a two stroke motor? What? Don't you pour it in the engine? No! And on the conversation went. No clue! We don't mean to be critical but sometimes one little detail (or lack of it) is all it takes to either screw something up or fix the problem.

 

[JB]

Re: 25w-40 synthetic blend merc oil...work in cold?

That seems reasonable to me, SS. What does Merc say??

 

[M9.9]

Re: 25w-40 synthetic blend merc oil...work in cold?

Seems to me that stuff (25w40) is thicker than grease and used in hot worker inboards, not outboards. I used 20/40 in my van years ago and at freezing the engine would'nt turn over fast enough to start. Never used anything over 10/30 in cold weather for any 4 stroke motor again.

 

[Fun Times]

Re: 25w-40 synthetic blend merc oil...work in cold?

What does Merc say??

Either 3 Quarts or 3 Liters of engine oil.

SAE 10W-30 viscosity oil is recommended
for use in all temperatures.

SAE 25W-40 viscosity oil may be used at
temperatures above 40? F (4? C).
Use Quicksilver 4-Cycle Marine Oil with
the proper viscosity for the expected
temperature in your area (see range
thermometer on left). If not available, use
a premium quality 4-cycle engine oil, certified
to meet or exceed anyone of the
following American Petroleum Institute
(API) service classifications SH, SG, SF,
CF-4, CE, CD, CDll.

 

[Faztbullet]

Re: 25w-40 synthetic blend merc oil...work in cold?

I use the StarBrite 10W 30 Pro Super Premium synthetic in all my customers 4 stoke engines...

 

[simplystressed]

Re: 25w-40 synthetic blend merc oil...work in cold?

Sorry guys I apologize for not being clearer (mobile phone and in hurry. As I edited above:

I have a 50hp merc 4 stroke and am currently running the Merc Outboard 25w40 synthetic blend oil. I've heard that regular 25w40 oil isn't recommended to use when its colder than 4c. I'm not sure if being synthetic helps with the temperature range.

Reason being might want to go on one last trip this year and its around -2c right now. If I warm it up for a while before going fast should it be ok?

 

[CharlieB]

Re: 25w-40 synthetic blend merc oil...work in cold?

Viscosity ratings for dino oil and full syn are the same, when in doubt follow the manufacturers guidelines for the temp range.

0W - 30 is a better option for the temps you are expecting.