Generator oil

Joined
Dec 7, 2003
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Location
Florida, Cape Coral
My new B&S generator suggest I use a 5w30 synthetic oil or a 10w30 oil. I was thinking a 10w30 synthetic might be best here in FL? Ed
 
Originally Posted by Oildudeny
5w30 synthetic is a better choice.

Why is that?
 
If it were my generator, I'd go with the highest quality 10w-30 HDEO (diesel oil) you can find. The diesel spec oils run on the thicker side of 30 weight and typically have more anti-wear additives that are limited in passenger car oils (due to potential catalytic converter poisoning.) No such catalyst issues on a generator engine.
 
With the number of post you have here on BITOG and the fact that you are in Florida, surely you have to be aware of the past posts by members like CUJET recommending thicker oils for air cooled engines on hot days. If I were you I would use Mobil 15W- 50, but if that seems too thick for you then a 15W - 40 , or a 10W - 40. Seriously in Florida you could even use a 20W- 50.

Getting the coolest air to you genset should be a top priority. Be sure it is not near any buildings walls that may restrict air flow and cause it to suck in some of the hot air coming off of it.
 
Originally Posted by JimPghPA
With the number of post you have here on BITOG and the fact that you are in Florida, surely you have to be aware of the past posts by members like CUJET recommending thicker oils for air cooled engines on hot days. If I were you I would use Mobil 15W- 50, but if that seems too thick for you then a 15W - 40 , or a 10W - 40. Seriously in Florida you could even use a 20W- 50.

Getting the coolest air to you genset should be a top priority. Be sure it is not near any buildings walls that may restrict air flow and cause it to suck in some of the hot air coming off of it.


Yep!, BITOG recommends 15W-40. Make it Redline
grin2.gif
 
Originally Posted by Oildudeny
you have over 15,000 posts.. why even question that?

What does the post count have to do with anything. I could have 40,000 posts of regurgitating marketing claims with out any practical knowledge on the subject at hand yet still consider myself an internet expert.
 
Originally Posted by Eddie
My new B&S generator suggest I use a 5w30 synthetic oil or a 10w30 oil. I was thinking a 10w30 synthetic might be best here in FL? Ed


Havent seen anyone recommend it yet.. but 5w40 gets you all seasons. Great in OPE, Powersports etc.

Rotella, Delo or Delvac are all pretty easy to obtain and fairly priced.
 
Anytime I've used a 50 weight in my riding mowers, I get a lot of aeration of the oil, evidenced by bubbles/foam on the dipstick after running. Not sure what causes this, but I avoid anything that thick in my OPE. I firmly believe that 30 and 40 weights are satisfactory for air cooled engines even in hotter climates.
 
Originally Posted by 92saturnsl2
Anytime I've used a 50 weight in my riding mowers, I get a lot of aeration of the oil, evidenced by bubbles/foam on the dipstick after running. Not sure what causes this, but I avoid anything that thick in my OPE. I firmly believe that 30 and 40 weights are satisfactory for air cooled engines even in hotter climates.


You are correct sir. My company installs generators and that's one of the reasons why the manufacturer recommends 5w-30 and 10w-30. But hey, what does the manufacturer know?
 
I read somewhere that you want to run a robust synthetic on the thinner side for generators, so the 5w30 full synthetic gets my vote. Remember to break it in by running it under various loads (idle, 500w, 1000w, 1500w, etc, each for an hour or two at a time) and then change the break in oil before calling it good.
 
Personally I've had good luck with 10w-30 M1 High Mileage in both of my generators. Presently they are filled with 5w-40 Rotella T6, but I may switch back. There is no good reason for a 5w-?? oil in your climate. 15w-40 does seem to be the preferred choice down your way, and it is now available in synthetic Rotella T6.
 
Thinking back to the 70s when I was into air-cooled Porsche engine rebuilding I do remember some interesting facts from the Porsche group. The cylinder and head temperature would increase if TOO heavy an oil were used. As best as I can remember Porsche ran straight 30 for racing events and 10w30 for street use. So when my B&S recommends a synthetic 5w30 and no heaver option, I wondered if thicker oil was found to increase the engine temp. I think I will stick with the recommended synthetic 5w30 or 10w30 synthetic. Ed
 
Originally Posted by krismoriah72
Originally Posted by Eddie
My new B&S generator suggest I use a 5w30 synthetic oil or a 10w30 oil. I was thinking a 10w30 synthetic might be best here in FL? Ed


Havent seen anyone recommend it yet.. but 5w40 gets you all seasons. Great in OPE, Powersports etc.

Rotella, Delo or Delvac are all pretty easy to obtain and fairly priced.



OP is in Florida. He has absolutely no need for a 5W anything, it never gets that cold there. And a 5w40 would be more likely to break down from it molecules sheering in an air cooled engine than a 10w40 or a 15w40.
 
Doesn't a thicker oil also mean more heat? How much and whether it's enough cause an issue is another story though.
 
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