Favorite Oil For 4-Cycle Spash-Oil System Engine ?

[951Indy]

Confession: When young and poor, I bought a cheap craftsman pushmower for my 3/4 acre lot. I couldnt justify a new one until it died, so as a test I left the same oil in the 6HP briggs for 13 years. It was Mobil 1 10w30. The factory fill was changed out after the first season. It finally succumbed to an ignition problem..

Now I use whatever is on sale.

 

[UNC017]

Rotella T5 or T6, or Delo 400. Mobil 1 Turbo Diesel Truck is fine also, but usually on the pricey side. The HDEOs are well-suited to modern power equipment engines.

 

[oldhp]

+1 on whatever is laying around. It currently has Mobil 1 0W20.
Maybe I'm getting a extra 100' per tankful now.........

 

[bubbatime]

This is what Briggs & Stratton has to say:

Oil Recommendation

SAE 30 40° F and higher (5° C and higher) is good for all purpose use above 40° F, use below 40° F will cause hard starting.

10W-30 0 to 100° F (-18 to 38° C) is better for varying temperature conditions. This grade of oil improves cold weather starting, but may increase oil consumption at 80° F(27° C) or higher.

Synthetic 5w30 -20 to 120° F (-30 to 40° C) provides the best protection at all temperatures as well as improved starting with less oil consumption.

5w30 40° F and below (5° C and below) is recommended for winter use, and works best in cold conditions.

Type of oil to use

Use a high quality detergent oil classified "For Service SF, SG, SH, SJ" or higher.

Do not use special additives.

Choose a viscosity according to the table above.

 

[bubbatime]

Originally Posted By: bubbatime
This is what Briggs & Stratton has to say:

Oil Recommendation

SAE 30 40° F and higher (5° C and higher) is good for all purpose use above 40° F, use below 40° F will cause hard starting.

10W-30 0 to 100° F (-18 to 38° C) is better for varying temperature conditions. This grade of oil improves cold weather starting, but may increase oil consumption at 80° F(27° C) or higher.

Synthetic 5w30 -20 to 120° F (-30 to 40° C) provides the best protection at all temperatures as well as improved starting with less oil consumption.

5w30 40° F and below (5° C and below) is recommended for winter use, and works best in cold conditions.

Type of oil to use

Use a high quality detergent oil classified "For Service SF, SG, SH, SJ" or higher.

Do not use special additives.

Choose a viscosity according to the table above.



That being said, in my observations in Florida (80-90 degrees for 8 months of the year), the best oil choice is a synthetic 5W30/synthetic 10W30, followed by SAE 30.

Lots of recommendations for Rotella T5 in this thread. Although a stout oil, it is still a mostly conventional semi synthetic and will consume oil above 80 degrees. I think SAE30 is a better choice for the op since he lives in Georgia if he decides not to use a synthetic XW30 as his first choice.

Briggs says to expect increased oil consumption using a conventional 10W30 above 80 degrees, and my observations have confirmed this.

 

[ChrisD46]

Curious if there is any concern to using a: "SN" rated passenger car motor oil ? Is the newer SN rated oil friendly to splash oil system lawn mowers , less friendly - or about the same as older rated SM or SJ ?

 

[Hokiefyd]

Originally Posted By: bubbatime
Briggs says to expect increased oil consumption using a conventional 10W30 above 80 degrees, and my observations have confirmed this.


That may be the case with those engines. I have two Honda vertical shaft engines (a GCV and a GXV) and neither consume any measurable amount of oil, regardless of the temperature. Together, they share 3-4 yards a week, so they get used a moderate amount. But Honda does recommend a conventional 10w30.

You are correct that Briggs' primary recommendation now is synthetic 5w30. With the OP having a Briggs engine, that certainly wouldn't be a bad choice.

 

[ARCOgraphite]

Originally Posted By: ChrisD46
Curious if there is any concern to using a: "SN" rated passenger car motor oil ? Is the newer SN rated oil friendly to splash oil system lawn mowers , less friendly - or about the same as older rated SM or SJ ?
Low HTHS PCMO may be fine in a mower but questionable to not worthy in snowblowers or light tractors. Current economy PCMoils are rated much better (less prone to sludging/varnishing) than SM and SM if you can ignore the zddp and MoDTC drop.

 

[kschachn]

Questionable in those applications? Why?

Originally Posted By: ARCOgraphite
Low HTHS PCMO may be fine in a mower but questionable to not worthy in snowblowers or light tractors. Current economy PCMoils are rated much better (less prone to sludging/varnishing) than SM and SM if you can ignore the zddp and MoDTC drop.

 

[wag123]

The best oil to use in a splash lubricated lawnmower engine is HD SAE30. This is what B&S recommends for temperatures above 40. Most types of lawn grasses don't grow at temperatures near 40, so you won't likely be using a mower at this low temperature anyway. I recommend and use Pennzoil conventional. High dollar boutique motor oils are a waste of money in a crude splash lubricated lawnmower engine.

 

[kschachn]

Why is it "the best"?

Originally Posted By: wag123
The best oil to use in a splash lubricated lawnmower engine is HD SAE30. This is what B&S recommends for temperatures above 40. Most types of lawn grasses don't grow at temperatures near 40, so you won't likely be using a mower at this low temperature anyway. I recommend and use Pennzoil conventional. High dollar boutique motor oils are a waste of money in a crude splash lubricated lawnmower engine.

 

[bubbatime]

Originally Posted By: kschachn
Why is it "the best"?

Originally Posted By: wag123
The best oil to use in a splash lubricated lawnmower engine is HD SAE30. This is what B&S recommends for temperatures above 40. Most types of lawn grasses don't grow at temperatures near 40, so you won't likely be using a mower at this low temperature anyway. I recommend and use Pennzoil conventional. High dollar boutique motor oils are a waste of money in a crude splash lubricated lawnmower engine.


That is his opinion. My opinion is that 5W30/10W30 synthetic can handle the high temps better, stays cleaner, consumes less, has less deposits on the oil rings/cylinders/valves, etc. SAE30 is a good choice too, but I think synthetic is better for this application.

 

[V8man]

If we are talikg about Mobil 1 or any other synthetic oil, is there a difference between 5w30 and 10w30, or does it really not matter in a SPLASH lubed small engine.

 

[gman2304]

Supertech, Pennzoil conventional,HD 30 wt. ALL the multi weight oils I have used would puff blue smoke on start up...from M1 to Pennzoil conventional! Sometimes my mower would smoke lightly for 5 minutes or more after starting to mow,but would finally clear up. 1998 JD LX188 with liquid cooled FD501V Kawasaki engine. On the engine sticker it reads...for temps from 0 to 32 degrees use 5w20...for temps above 32 degrees use 30 wt HD. Yes it's 15 years old but I don't think the recommendations have changed much on newer OPE. I've used 30 wt HD for years now with no smoke on startup...and no oil consumption problems. If all else fails ...follow the engine manufacturers recommendations. I think you will see that 30wt HD is still recommended by most small engine mfrs, especially in hot weather conditions. If you're blowing snow in MN then thats an entirely different story. Thanks

 

[wag123]

Originally Posted By: kschachn
Why is it "the best"?

Originally Posted By: wag123
The best oil to use in a splash lubricated lawnmower engine is HD SAE30. This is what B&S recommends for temperatures above 40. Most types of lawn grasses don't grow at temperatures near 40, so you won't likely be using a mower at this low temperature anyway. I recommend and use Pennzoil conventional. High dollar boutique motor oils are a waste of money in a crude splash lubricated lawnmower engine.

1. A good HD SAE30 is very shear stable and holds-up better to the very high temperatures that you encounter with air cooled engines operated with high loads (mulching mowers) in high ambient temperatures.
2. It is cheaper!
3. You don't need to add oil as often between oil changes because it doesn't burn off as much.
4. Because it doesn't burn off as much, the engine doesn't carbon-up as much.
5. It is more oil with fewer additives and NO VII. As such, it is much more resistant to sludging.
6. In the over 25 years that I have been working on small engines, I have never seen a lubrication related engine failure where a quality SAE30 oil was used, accept if the engine was overfilled with oil or run out of oil. I HAVE seen lubrication related engine failures from the use of multi-weight motor oils.
6. SAE30 is the oil that B&S recommends for use above 40 degrees and it is the oil that B&S has recommended for over 70 years.

You guys can use whatever you like, but I'm telling you that a quality HD SAE30 is all you will ever have to use in an air cooled lawnmower engine. Personally, I only recommend multi-weight oils be used in snow blowers, generators used in the winter, and liquid cooled small engines.

 

[oldhp]

How do you tell engine failure is from multi-weight oil?

 

[wag123]

Simple, I asked the customer what oil they had been using in their engine.
The failures that I have seen were generally thrown rods, but I have also seen a couple with seized upper crankshaft bearings. The oil was as black as tar and had an almost jelly like consistency. Also, the oil smells BAD, I mean REALLY BAD! It has a distinctive strong burnt odor to it.

 

[V8man]

Originally Posted By: wag123
Simple, I asked the customer what oil they had been using in their engine.
The failures that I have seen were generally thrown rods, but I have also seen a couple with seized upper crankshaft bearings. The oil was as black as tar and had an almost jelly like consistency. Also, the oil smells BAD, I mean REALLY BAD! It has a distinctive strong burnt odor to it.


Sounds like it was from not changing the oil, same thing might happen with a 30W if it was not changed.

 

[wag123]

Listen guys, this topic comes up again and again at virtually every OPE Technician training school that I have ever attended. These schools are something the OPE manufacturers require that we attend every year to maintain our dealer status. Every time this subject comes up, the advice that the factory trainers always give is to use a quality HD SAE30 motor oil in our customer's lawnmowers.

 

[TFB1]

Originally Posted By: V8man


Sounds like it was from not changing the oil, same thing might happen with a 30W if it was not changed.


Agreed, nothing wrong with a good synthetic in a air cooled engine, I have Mobil 1 0W-40 in my well used Honda freebee I got back in '11... It's never smoked & almost two years later hasn't used enough oil to add any(yes it still has the same fill from almost two years ago)...

I have a 1980 B&S that lists 5W-20 for winter operation, so like the auto mfgrs, recommendations are all over the place... Basically as long as the oil is changed occasionally, most will run on anything(including non-detergent) and lead a long and happy life...