The real reason to use single grade 30 weight...

[Garak]

Originally Posted By: Joe90_guy
I've said this many times on BITOG.

That may be true, Joe, but I've said a number of times on BITOG that I don't have a lot of faith in most OPE. The fuel systems are enough of a weakness and most of the equipment is so cheap as to be throwaway these days. When my lawnmower's carb puked after one season (you know how Saskatchewan has such an insanely long summer and we're using mowers constantly, after all), the only thing that saved it was my small engine guy decided to be kind to me and got the work done for next to nothing. The kits aren't available to the public up here, and the carb in Canada was worth more than the engine itself.

While I'm a BITOGer and will do oil changes on the thing, realistically, there is absolutely no reason why I should. I'd save myself time and money by just keeping the oil topped up, with whatever I happen to have laying on the shelf, no matter what the Noack or additive package or viscosity. The engine isn't going to blow up. Something in the fuel system is going to go south again first.

I'm going to spend more on carb maintenance than I'll ever need to spend on oil for the thing. That goes for my snowblower, too, and my snowmobile, for that matter.

 

[Joe90_guy]

Garak,
Apologies. When I saw this post come up in the left hand side bar, I didn't realise it was for lawn mower engines. My post was directed at gasoline engined cars.
Joe

 

[TiredTrucker]

Or the Amsoil 10w30/30 synthetic which uses no VI's and has a NOACK of 4.0 Doesn't matter. I use the same HDEO 10w30 CJ-4/SM that my semi truck gets in my Yamaha EF2000is portable generator and my John Deere Z445 mower with a Kawasaki engine. The add pack of this oil is the main reason I like it, and I don't have to stock a bunch of different oils.

 

[CT8]

I use what ever left over oil I have,5w30 from the gas vehicles 15w40 from the diesels. The high out puts a Generator and a 13 hp pressure washer get the 15w40 the push type lawn mowers get what ever.

 

[Garak]

Originally Posted By: Joe90_guy
Apologies. When I saw this post come up in the left hand side bar, I didn't realise it was for lawn mower engines. My post was directed at gasoline engined cars.

Don't be sorry at all. Your information is always appreciated. I just found it a good time to have one of my rants against small engine fuel systems.

See, the common thing, at least in my experience and those who I know is that when your OPE is all screwed up at the start of the season and won't start and it's so bad that you have to take it in, they ask if you left the fuel in. If you did, they will tell you that you should have ran it dry. If you ran it dry, they'll tell you that you should have left the fuel in. If you used Stabil, you shouldn't have. If you did not, you should have. And don't even mention ethanol blended fuel.

Basically, they're trying to cover for the parts that they put on that are actually worth about eighty cents, yet come with a hefty markup and a large labour bill.

 

[SuperSalad]

I am confused about how NOACK volatility and multi-grade/monograde are dependent on one another. I could formulate a monograde 30 with 20% volatility or just as easily a multigrade 10w30 with 4% volatility. It all depends on formulation and you may or may not be surprised to find out that many monograde 30's are secretly 25w30's or lower in disguise (gasp)

 

[userfriendly]

And with the current group III glut, I bet a lot of the better mono-grades are jacked-up on "synthetic".
I watch engine oils like Pet-Can Duron SAE 30, Mobil's 1630 and Chevron's 15W30.
All mono-grades to me, but with very good cold performance.

 

[Garak]

Of course, all you state is quite true. However, we do know that your best odds of getting a low Noack, particularly at a very low price, involve a monograde or another low VI oil, very generally speaking. This is most noticeable, obviously, if you're comparing products in the same product line, rather than cherry picking a terrible outlier of a monograde versus some multigrade that happens to have very low Noack, such as some of the Pennzoil examples we've seen, or other multigrades that have a low Noack as part of the certifications they possess.

Basically, if I want a 30 grade low Noack oil for my lawnmower (if Noack were really important to me and my lawnmower), without going on a real hunt, and I see GTX 5w30 and GTX SAE 30 in front of me, I would suggest that it would be a fair assumption that the GTX SAE 30 would have the lower Noack. If, instead of GTX 5w30, the multigrade 30 were 0w30 A3/B4 or 5w30 A3/B4 or some of the Pennzoil examples we've seen, well, my odds would get worse.

 

[Shannow]

Originally Posted By: MotoTribologist
I am confused about how NOACK volatility and multi-grade/monograde are dependent on one another. I could formulate a monograde 30 with 20% volatility or just as easily a multigrade 10w30 with 4% volatility. It all depends on formulation and you may or may not be surprised to find out that many monograde 30's are secretly 25w30's or lower in disguise (gasp)

Nah, not surprised.

In order to be a monograde, they can't be formulated with viscosity modifiers...

They MAY meet one or more multigrade performance specs, but only as a monograde do they have the choice to market them as a mono, multi, or both...and only then at the coldest "W" rating that they meet.

So if it's an SAE30, it shan't contain VII

edit...what base oil would you start with to get a 20% NOACK SAE30 ?

 

[fdcg27]

May I expand upon your post a bit?
There was a day when someone here discovered the acronym "NOACK".
They then decided that lower NOACK must always and everywhere be an important thing.
Meanwhile, those of us who've owned things with engines for a few decades and have in past eras used high NOACK oils in those engines never saw any problems, nor did we see any deposit accumulation. Rather, our engines stayed clean and ran well for many hours on oils of Lord knows how high a NOACK volatility.
Is lower volatility probably a good thing?
Sure.
Is it all-important?
Apparently not.
As Garak pointed out, you'll typically have more fuel system problems with anything that relies upon a carb than you will with anything remotely related to the engine oil.
Let's not go on to older VIIs and shear stability as well as deposits. We used those oils as well without incident.
Are oils better today?
Sure, since we would not otherwise be having these sorts of how many angels fit on the head of a pin discussions.

 

[userfriendly]

I look at the flash point, if it is very high, I assume the volatility (and noack) is low.

 

[Garak]

Originally Posted By: fdcg27
As Garak pointed out, you'll typically have more fuel system problems with anything that relies upon a carb than you will with anything remotely related to the engine oil.

Heck, these days, you buy a new lawnmower, you can do all kinds of strange things with maintenance, including ignoring the detergent oil requirement, and grab a non-detergent monograde, or something totally weird for viscosity, and still have the engine outlast the fuel system by a wide margin. I'm still steamed about my lawnmower's problems, and it never saw a drop of E10, but, of course, that's what the small engine guys like to blame.

 

[NH73]

Originally Posted By: Garak
Originally Posted By: fdcg27
As Garak pointed out, you'll typically have more fuel system problems with anything that relies upon a carb than you will with anything remotely related to the engine oil.

Heck, these days, you buy a new lawnmower, you can do all kinds of strange things with maintenance, including ignoring the detergent oil requirement, and grab a non-detergent monograde, or something totally weird for viscosity, and still have the engine outlast the fuel system by a wide margin. I'm still steamed about my lawnmower's problems, and it never saw a drop of E10, but, of course, that's what the small engine guys like to blame.


Yes, E10 gets blamed a lot. Some warranted, some not. I use E10 in my stuff with a dose of Stabil. Only problem was one time on the snowblower, B&S engine, the jet clogged.

 

[fdcg27]

Originally Posted By: Garak
Originally Posted By: fdcg27
As Garak pointed out, you'll typically have more fuel system problems with anything that relies upon a carb than you will with anything remotely related to the engine oil.

Heck, these days, you buy a new lawnmower, you can do all kinds of strange things with maintenance, including ignoring the detergent oil requirement, and grab a non-detergent monograde, or something totally weird for viscosity, and still have the engine outlast the fuel system by a wide margin. I'm still steamed about my lawnmower's problems, and it never saw a drop of E10, but, of course, that's what the small engine guys like to blame.


These little guys really don't seem all that much affected by oil choice as long as you keep oil in them.
I know that E10 is everyone's favorite culprit for any running problems with OPEs, but E10 has been about all you're going to get in my area for the past twenty years at least and I've never had any problems running it in my OPEs.
Some of these engines simply have lousy fuel systems including carbs.
It's the design, not the fuel.

 

[Garak]

Yes, I'd prefer to avoid E10 for OPE, but, as you point out, that isn't an option for everyone. And, unfortunately, it does mechanics and OEMs no good to simply blame E10. Spend more than eighty cents on parts when manufacturing a fuel system. That might work wonders. When my carb puked up the gas, it certainly had nothing to do with E10.

The carb in the States was worth about $30. Up here, they wanted $200, which is more than the price of the replacement engine. And, I know the carb didn't cost anywhere near $30 to build, much less $200. $3 would be a stretch.

 

[Garak]

I use Stabil, too, but not sure how much it helps. I guess as long as it doesn't hurt.