Isn't 15w-40 motor oil a bit thick for mowers?

[1999nick]

quote:

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Originally posted by ZmOz:
Well, first of all how many people mow in the winter? No, it is not too thick. Cold it's thinner than a straight 30 weight. Hot it's pretty thin too, with 3-500 degree oil temps.

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I use my mower, a Honda 5.5 hp, year-round. In December and January I use it to keep the leaves picked up and the yard neatened up. I have several oak trees in my yard that shed leaves all winter long. I have been using Mobil 1 5-30 the last few years, with no consumption. I change once a year, in December or January. My present oil has been in there 12 months, and the dipstick still shows a quarter inch above full, and is still a nice golden color.

I just bought a couple of quarts of M1 0-30, which I am going to use in my next change in a couple of weeks. Should make starting even easier, and I'll watch to see if consumption increases. By the way, it is 28 degrees here in Tennessee right now. Maybe I ought to put that 0-30 in today.

 

[Bamaro]

I have 20W-50 in both of my lawnmowers. Seems that it should be better than a straight 30 since only used in warm months.

 

[Bror Jace]

Bamaro, MolaKule found that 20W-50 in air-cooled engines caused them to run hotter because the resistance to flow/splash/etc ... was so great.

--- Bror Jace

 

[passgas55]

Gas powered equipment that I have-(1)12 hp bs riding lawnmower,(1) 11 hp honda powered bush hog,(1)6 hp bs,(1) 3hp bs edger,(1) 8 hp bs generator. All the oil gets changed in the spring before the first cut of the season. The riding mower at midseason because it is used the most.I use Super Tech syn 10/30 and buy it by the gallon.Works good for me.

 

[Bamaro]

quote:

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Originally posted by Bror Jace:
Bamaro, MolaKule found that 20W-50 in air-cooled engines caused them to run hotter because the resistance to flow/splash/etc ... was so great.

--- Bror Jace

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If the manufacturer recommends straight 30, wouldn't 20W-50 flow at least as good as the 30?

 

[fractal]

quote:

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Originally posted by Rob Taggs:
I have seen many folks posting the use of 15w-40 oils in mowers. That sure seems awful thick for a mower!

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It would depend on the mower. I would not run 15w40 in a briggs and stratton motor, but other manufacturers may permit it.

http://www.briggsandstratton.com/display/router.asp?docid=64066

is very specific on what you should and should not use in a briggs and stratton motor. Somewhere on that site that I can not find right now has the explanation why you should not use 15w40 in a splash lubricated briggs and stratton motor.

 

[Bror Jace]

"Somewhere on that site that I can not find right now has the explanation why you should not use 15w40 in a splash lubricated briggs and stratton motor."

I looked at your link, looked at a few appropriate links on that page and even used their search engine but could not find a single reference to 15W-40 oils.

We've discussed this before and we've found B&S's oil recommendatuions to be a bit vague and they seem to buy into some mineral vs. synthetic oil myths ... while they don't acknowledge the difference between real synthetics and Group III oils. Nor do they even address synthetic blends.

Sorry, but I just don't put much weight in their specific recommendations.

--- Bror Jace

 

[tdi-rick]

I suppose it all depends on ambient and load conditions.
I used 15w-40 HDEO oils in B&S (side banger and Vanguard) customers engines that were running on average 40 hours per week, 46-48 weeks per year (refrigerated trucks) and they lasted a loooong time. They were operated in conditions up to 45*C/113*F. They didn't really need to be run when it was 0*C/32*F.

Crikey, I've got an old 2.5kVa B&S powered generator that is 30 years old that has only ever had 20w-50 or 15w-40 in it, as they were the lightest oil viscosities commonly available here for years.

I'm actually going through the process of "do I buy an Xw-30, or use some of the Delvac 1 I have in stock ?" for two new Honda OHC engines.

 

[JT]

For almost 20 years I ran 15W40 in my 20 horse air cooled B&S Craftsman rider and I use the same in my 10 year old 6 horse walk behind. Never had a problem. The 15W40 was recommended by a small engine repairman I knew, with 40+ years of experience. I sold the rider and switched over to a diesel powered zero turn this past spring and switched to a 5W40 synthetic.

I had the same 15W40 in my 12 horse air cooled B&S generator, no problems for the past 7 years, 2 weeks ago we had a power outage and the outside temp was -10, the !@#$ thing would start and immediately shutdown, (sensing a low oil condition). I swapped out the 15W with a 0W30 and it ran fine. I'll be sticking with the 0W30 in the generator.

 

[cos]

While a 15W40 offer better protection for a push mower sounds it is thicker than a straight 30W when hot. How about Chevron Delo 400 10W30?

 

[Bror Jace]

cos, we’re not sure which is thicker at 250F-300F ... a straight 30 or a 15W-40. oils are tested hot at 212F. It could be a totally different ballgame at temps 20-50% higher.

Chevron Delo400 in 10W-30 sounds great for cooler temps where a 15W-40 would be too thick ... or at least less than ideal. But it’s very difficult to find.

While our new Ariens snowblower is brand new, I’m using a high-mileage 10W-30 in it ... Pennzoil High Mileage Vehicle.

--- Bror Jace

 

[jagabom]

 

[jagabom]

I have one of those low oil sensors on my generator as well. The 1st time it lets me down it will be removed. I watch the oil level in my stuff. My neighbor had the low oil lite come on in his truck but he never tkaes care of it.

Jim
CYWG

 

[2004 F150 4x4]

You guys wanting to use, but not locating Delo 400 in 10w-30 need to visit your local Case Tractor Dealership. They sale a Case branded oil in 10w-30 that would be close to the Delo in performance.

 

[Flashlightboy]

I just bought a Craftsman push mower with the B&S 6.5 Quantum engine.

The manual calls for a straight 30w (different from the B&S site) however the initial fill will be (we can't do this with cars!!!) will be M1 Truck & SUV.

Now, I've got to find me a fancy pants Iridium plug!!!!

 

[JonS]

At 300f, a 15w-40 is 5.19 cst
At 300f, a sae30 is 4.68 cst
But, at 50f a 15w-40 is 688cst
and a sae 30 is 619 cst.
So a sae 30 would be better in 50f weather than a 15w-40, but at 300f a 15w-40 would do the trick.
By the way, i ran a temp test last year using sae 30 in my mower. The temps after 1/2 of use in 70f weather the oil was at 200f.