NOT another oil debate!!

[fieromx3]

i thought this would have been the easiest thing to find on the internet..... what viscosity oil is recommended???

my manual says an SAE 30 oil, mercruiser recommends their 20w-40 but is that for their newer engines??

also read using full synthetics is not recommended yet their quicksilver oil is advertised at full synthetic... wtf??

my engine is a 1977 mercruiser 140 it is a new engine and doing its first oil change and couldnt find any info on what oil to use....

this is NOT and oil debate i dont care about opinion on brands to use and yadda yadda i just want to know what viscosity to use and synthetic or not. if the quicksilver 20w-40 is recommended then i will use it

 

[Eric 3.7LX Alpha 1]

Re: NOT another oil debate!!

Mercruiser Service Manual #2 page 1 C-3

What changes your viscosity is the ambient air temperature your boating in.
If your boating between 32?F and 90?F majority of the time, it's SAE 30.

 

[fieromx3]

Re: NOT another oil debate!!

finding a straight sae 30 oil here is really difficult.... what about using a bi-viscosity oil??? and using synthetic? i want to treat this thing as good as possible but dont want to ruin it over something as dumb as oil.

 

[achris]

Re: NOT another oil debate!!

The first couple of changes of oil on a new engine should NOT contain friction modifiers. The 'running-in' process requires a certain amount of friction between the piston rings and the cylinder walls, so they form as best a seal as possible. And the best oil for that is the cheapest Wallymart oil you can find (of the right weight). Once that has happened, then by all means use the best most expensive oil you can find....

Unfortunately I am behind a proxy at the moment and can't upload any pictures, but if you have a look in the latest Merc manuals, they all say the same thing. This is a link to the manual for the 1998 and later 4 cylinder engines... Have a look on page 9 of section 1B...

https://docs.google.com/viewer?a=v&...ZDU4ZS00NzcwLWI1MGYtMTQwMzc3MTJiYTdl&hl=en_GB

Chris.....

 

[achris]

Re: NOT another oil debate!!

finding a straight sae 30 oil here is really difficult.... what about using a bi-viscosity oil??? and using synthetic? i want to treat this thing as good as possible but dont want to ruin it over something as dumb as oil.

If you can't find a straight weigh oil (I also have trouble with that) use a good quality 25W-40 oil... As recommended in any of the latest Merc manuals. I doubt anyone has damaged an engine with the wrong oil. Not enough oil, or oil that hasn't been changed for 10 years, yes... but that's a different issue altogether...

Without trying to start a 'which oil is best' debate... I use a diesel engine oil, just because of the extra shear strength it has, and I run my engines HARD....

Chris...........

 

[fieromx3]

Re: NOT another oil debate!!

thanks for the post achris!!! its really helpful

 

[Silvertip]

Re: NOT another oil debate!!

Where are you looking for oil. 30W oil is common as sliced bread at most farm stores as well as auto stores.

 

[HT32BSX115]

Re: NOT another oil debate!!

Without trying to start a 'which oil is best' debate... I use a diesel engine oil, just because of the extra shear strength it has, and I run my engines HARD....

Chris...........

I use xxx oil and I've never had a problem!

 

[achris]

Re: NOT another oil debate!!

I use xxx oil and I've never had a problem!

Rick, you were told not to start

 

[HT32BSX115]

Re: NOT another oil debate!!

Rick, you were told not to start

I couldn't help myself!