Oil spec's

[Jermlives2ride]

My issue is trying to figure out what brand of oil for my 383 hammerhead everyone's referring to 15w-40 which is fine except there fact that 15w-40 is a diesel oil and know one is clarifying if that's ok to use in the gas 383 hammerhead motor ? Any to clear the air ? 

[csleaver]

I always used Castrol HD 40, or similar, oil in the Hammerhead 383 engines.

https://www.amazon.com/Castrol-06143-6PK-HD40-Motor-Quart/dp/B00B9XDM0C

[smileysteve]

36 minutes ago, Jermlives2ride said:

My issue is trying to figure out what brand of oil for my 383 hammerhead everyone's referring to 15w-40 which is fine except there fact that 15w-40 is a diesel oil and know one is clarifying if that's ok to use in the gas 383 hammerhead motor ? Any to clear the air ? 

Yes. "Diesel" oil is great for boats; it means it has additives for high load, high pressure, high blowby symptoms - many characteristics of a boat running (though less, and where water is contributing rather than a high pressure fuel system)

Valvoline has a 15w40 synthetic blend that's diesel certified if you're cheap, but going full synthetic is smarter. Synthetic and higher cold flow oils last longer, don't break down as much under load, and flow better for cold starts (a consumer boat has a lot of cold starts)

Edited June 18, 2022 by smileysteve

[justgary]

I use 15W-40 diesel oil also, but I stick with a brand that carries an S rating as well as a C rating.  Rotella dropped their S rating a few years back, so many of us switched to Delo.

[ThinBuLine]

I’m surprised I don’t here more people using amsoil products on here. 
 

I have been using them for the past few years in my vehicles and after some oil analysis, am blown away by the results. 
 

Is there a reason why people aren’t using them in their boats? Just got my boat last year and all the fluids in the boat were switched to amsoil this year. 
 

hopefully I get the same results out of them. 

[SkiPablo]

Yes any diesel oil is what you want.   With the hammerhead I'd be tempted to run 15w50 Mobil 1 b/c it's a tad thicker.

[oldjeep]

20 hours ago, ThinBuLine said:

 

Is there a reason why people aren’t using them in their boats? Just got my boat last year and all the fluids in the boat were switched to amsoil this year. 
 

hopefully I get the same results out of them. 

Yes, because while amsoil may be good oil - it is also a cult;)

[electricjohn]

35 minutes ago, oldjeep said:

Yes, because while amsoil may be good oil - it is also a cult;)

And nobody makes a bad oil.

[Jermlives2ride]

On 6/18/2022 at 8:34 AM, smileysteve said:

Yes. "Diesel" oil is great for boats; it means it has additives for high load, high pressure, high blowby symptoms - many characteristics of a boat running (though less, and where water is contributing rather than a high pressure fuel system)

Valvoline has a 15w40 synthetic blend that's diesel certified if you're cheap, but going full synthetic is smarter. Synthetic and higher cold flow oils last longer, don't break down as much under load, and flow better for cold starts (a consumer boat has a lot of cold starts)

Thanks this helps appreciate it