Mobil 1 15w-50

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Does anyone use this in their mowers/ OPE? I am thinking this is what I am going to go with for my next oil change very soon.
 
I’ve used Rotella T5 in my Kawasaki 501v for years with great results. Having said that the Mobil 1 15w50 is a great choice for OPE engines and hydro‘s, though a bit pricey. I’ve used it exclusively in my 1998 Tuff Torq K61 hydro since dumping the factory fill years ago and it still performs as new.
 
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Some Kohler and Kawasaki engines list 20W-50 as an acceptable or even preferred weight.

I have a 5gal bucket of Castrol 20W-50 that I've been using to top off the hydros/oil on my two older zero turns. They both have at least 50% 20W-50 in the sump by now. Probably close to 100% on one of them. Can't tell any difference.
 
15W-50 is an ideal oil for very hot engines. I've mentioned my Honda water pump failures due to overheating. I was de-watering my overgrown FL acreage property prior to environmental evaluation... (you get the idea). The pumps ran 24/7 and both failed on conventional oil. Honda was good enough to honor the warranty, and yes, I changed the oil every day. They got so hot, the oil was water thin and full of glitter after a day's use.

The replacement pump ended up being a Kawasaki, and fed 15W-50. It's still in good running condition, despite it's age. An even higher number of hours than the Honda pumps survived. That's 100% due to the oil choice for my conditions.

My Subaru 11HP generator uses M1, 15W-50 also. It's been seriously abused, during the construction of my house, and during 4 hurricanes. One of which had us out of power for 6 months. It's oil temperature runs as much as 265 degrees F. Many thousands of trouble free hours. (guessing near 4500)

As a very general rule, the classic straight 30 motor oil that OPE typically used had an HTHS of 3.8. Today's 5w30 oils fall short at about 3.1.

So, I'd put it this way, "IF" you have an older engine, or an engine with known high oil temperature, or one that is subject to very hot conditions (such as a generator in stagnant air after a South Florida Hurricane) choose an oil with an HTHS of at least 3.8.

M1, 15W-50 is, I think, 4.5 HTHS. And, no it's not too thick for air cooled engines.

I might add that I use a HF thermocouple and simply dip it in the oil after a run. It's interesting to note which engines run hot and which don't. Tecumseh bush hog runs HOT, I've seen 270! Honda 190 mower, nowhere near as hot at about 210. Honda 390 pressure washer, about 220. I should make a chart.
 
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Obiligatory "What does the manual say"

My friend has a JD with a Kawasaki motor and mows several acres. Nothing more than 10w30 has ever been used and it consumes nothing in a two year mowing season.

I would certainly not go out of my way to use 15w-50 unless it was left over from something else. (i.e. don't buy it for this application)
 
I use Mystik 15w50 in my gas air compressor on my truck. It has very little air flow around it and will sometimes run for hours on end. All of the other stuff gets 15w40 Schaeffer or some cheap 10w30 depending on what it is.
 
most air cooled engines get quite hot + oils continue to thin past their hot spec a 212F + REAL synthetics thin less!!!!
 
I use the 15-50 Mobil 1 in my Moto Guzzi motorcycle. Been doing that for over 35 years.

Flat tappet V twin , 1000cc (948cc actual) the highest mileage was over 350,000 mile when i sold the bike.

Its still on the road. (Moto Guzzi Eldorado with a big bore kit 850 to 1000 cc)

Still using Mobil 1 in all of my current rides ,is is not 70,000 miles 1976 Convert. See list below.

Oil usually bought at Walmart etc.

1972 Eldorado new to me so "0" miles so far
1972 AMBASSADOR 169000 MILES
1978 G5 170000 MILES
1973 V7 SPORT 25000 MILES
1973 ELDORADO 300000+ MILES
1980 CX100 50 MILES
1976 CONVERT-62000 MILES AND BUILDING
1976 HONDA CB400F 27 MILES AND BUILDING SOLD

MGNOC # 2723

Tom
 
15W-50 is an ideal oil for very hot engines. I've mentioned my Honda water pump failures due to overheating. I was de-watering my overgrown FL acreage property prior to environmental evaluation... (you get the idea). The pumps ran 24/7 and both failed on conventional oil. Honda was good enough to honor the warranty, and yes, I changed the oil every day. They got so hot, the oil was water thin and full of glitter after a day's use.

The replacement pump ended up being a Kawasaki, and fed 15W-50. It's still in good running condition, despite it's age. An even higher number of hours than the Honda pumps survived. That's 100% due to the oil choice for my conditions.

My Subaru 11HP generator uses M1, 15W-50 also. It's been seriously abused, during the construction of my house, and during 4 hurricanes. One of which had us out of power for 6 months. It's oil temperature runs as much as 265 degrees F. Many thousands of trouble free hours. (guessing near 4500)

As a very general rule, the classic straight 30 motor oil that OPE typically used had an HTHS of 3.8. Today's 5w30 oils fall short at about 3.1.

So, I'd put it this way, "IF" you have an older engine, or an engine with known high oil temperature, or one that is subject to very hot conditions (such as a generator in stagnant air after a South Florida Hurricane) choose an oil with an HTHS of at least 3.8.

M1, 15W-50 is, I think, 4.5 HTHS. And, no it's not too thick for air cooled engines.

I might add that I use a HF thermocouple and simply dip it in the oil after a run. It's interesting to note which engines run hot and which don't. Tecumseh bush hog runs HOT, I've seen 270! Honda 190 mower, nowhere near as hot at about 210. Honda 390 pressure washer, about 220. I should make a chart.
Thanks for the good info! According to M1 it has a HTHS of 4.5
 
Been running it in my 2004 TroyBilt 6.5hp pretty much since after break-in, and after finding that it consumes 30W, even though that's what it's supposed to run on. It's pretty much the only oil I've used in it that it doesn't consume.
 
I used Napa 15w50
Sucked out all the HP.
Me no like and I have an oil cooler anyway.
 
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