Oil for Kohler 20RCA generator - says fully synthetic API 5W-30 rated SG SH or SJ

I keep 5W40 full synthetic in my portable generator - because I bought a jug of Chevron Delo full synthetic on close out -I use to use 5W30 full synthetic.

If I need it in the winter I am good to go - and if I still need it the next day I would use 5W30 or 5W40 depending on my mood.

But if after a hurricane and it is 102 degrees outside I would start off with the 5W40 full synthetic because I want to get the power back on - but as soon as I had the chance I would swap it out for 15W40.

I understand changing the oil in a stand by unit is harder than changing the oil in a portable -
my portable unit cost $900 - if I spent $14K on a standby unit I would not be trying to save $15 on oil - I would use quality oil appropriate for the outside temp and change it often.

I may even look into one of those oil vacuum things that suck the oil out of the dipstick on cars -

If the standby unit called for oil change every 200 hours I could see myself sucking the oil out every 50 hours and changing the filter at 150. This is what I did with my motorcycle. To try a scrimp on oil changes when you have an expensive "mission critical" unit - it seems crazy to not over maintain it.
 
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For me 0 bottom numbers get consumed more in stationary air cooled units. I can't speak to big liquid ones.
I've tried 0w in one Generac and it used oil, back to 5-30w and no more consumption. Now in recoil start portable units that get stored in cold unheated areas then that oil is a must in them to get them to spin over fast enough to start in 0f temps and those units rarely saw 80f.
If I was down south in the heat, with barely if any below freezing winter temps it would be at least a 10-40w oil if not 15-50w.

Unless you live someplace with extreme cold there is little reason to use 0W oil in air cooled power equipment.

I could see it in a snow blower because you run them for a couple hours at a time (usually) and can check the oil lever between use.

A generator that will run 10+ hours straight - I don't want 0w anything.

What % of OPE had oil related issues because the start up oil was "too thick"? Yes you need to be able to start it.

VS

What % of OPE had oil related issues because oil was "too thin" and lost protective film, oil degraded or oil level got low and engine cratered?

Too thick at start up VS too thin at extended use - 1 in 1,000 - 1 in 10,000?
 
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Unless you live someplace with extreme cold there is little reason to use 0W oil in air cooled power equipment.

I could see it in a snow blower because you run them for a couple hours at a time (usually) and can check the oil lever between use.

A generator that will run 10+ hours straight - I don't want 0w anything.

What % of OPE had oil related issues because the start up oil was "too thick"? Yes you need to be able to start it.

VS

What % of OPE had oil related issues because oil was "too thin" and lost protective film, oil degraded or oil level got low and engine cratered?

Too thick at start up VS too thin at extended use - 1 in 1,000 - 1 in 10,000?

Not to be dismissive or pedantic here, but what exactly is your motivation for wanting to change people’s oil preference in their OPE? Going over the hundreds of UOAs of various 0/5w-30/40 here in engines ranging from the Great White North down to the Southernmost tips of TX and FL aren’t showing any issues with running those. It’s been discussed by folks more knowledgeable on this subject than I that a 0/5W-40 will *typically* use a significantly higher quality base stock and VII than a narrower spread 15w-40.

I guess what I’m saying is, if you like your 15w-40, go ahead and use it. Not sure why you’re putting so much effort into trying to change everyone’s mind on it.
 
A generator that will run 10+ hours straight - I don't want 0w anything.

What % of OPE had oil related issues because the start up oil was "too thick"? Yes you need to be able to start it.
VS
What % of OPE had oil related issues because oil was "too thin" and lost protective film, oil degraded or oil level got low and engine cratered?

Too thick at start up VS too thin at extended use - 1 in 1,000 - 1 in 10,000?
Dude, you don't even know what you're talking about. The 0W-40 oil I use with Porsche A40 approval is not "too thin at extended use" nor is it degraded.
 
Dude, you don't even know what you're talking about. The 0W-40 oil I use with Porsche A40 approval is not "too thin at extended use" nor is it degraded.
I’ll be putting HPL Supercar 5w-40 in mine (lol) simply because it’s what I’ve standardized in my vehicles and it simplifies the various oils I used to keep on the shelf. Probably WAYYY overkill, but most of my OPE uses less than a quart in their sumps.
 
Natural gas engines have slightly different "optimal" oils because they run so clean. So you don't need the huge soot management of a diesel rated oil, for example.

Large industrial engines running on natural gas will use an SAE 40 Mobil Pegasus 1005 or Shell Mysella XL.

Personally, if I owned a natural-gas powered generator, I would be using Valvoline Premium Blue One Solution because it at least has some natural-gas specific testing and verification.
 
Off topic: My 2017 RECSA Natural Gas Kohler Standby Generator was designed with an " abbnynornal brain". It would overcharge the battery at a constant 13.9 volts. I had read about this on 2016 models, not on any 2017 models. So, being the " Capt. Klusoe" that I am, doing my own maintenance , I would pop the caps on the FLA 51R battery 3X a year. Acid all over the place. Re-fill the battery with distilled water. Lock it up for another 3 months. Did this for a year, then got tired of doing it. Called Corporate Kohler, explained my situation. They wouldn't believe me. Said design flaw was fixed in 2016.......... Then I showed them pics of all the splattered battery acid. and the LED readout out 13.9 volts. Well, that changed everything. All of a sudden, the red carpet came out ! I thought a I was a Hollywood Star !!!! :) Nice feeling :) They set up an appointment to replace the ENTIRE brain of the machine with an upgraded version, install a new battery, clean the brushes on the generator, do an oil change, change the air filter, re-set the brain to my transfer swich, re-set the maintenance minder. All on a Saturday at my specified time. The technician said the brain must have slipped in during manufacturing ( Yeah, OK buddy ) The whole thing was so hush hush. Did some research, their 2016 models were blowing up battries all over the country !!!. I wonder how many other 2017 models slipped thru with th bad brains ????? Now it float charges at 13.3 volts. Just an FYI for anyone who has a 2017 Kohler RESCA naural gas generator in their yard. Check the battery flost volts. 13.3 IS the number.
 
Big difference ! The year I blew the whistle on them , this happened. It was due for maintenance, so I gathered all my stuff and stuck it in a Home Depot bucket. The machine is fairly far from the house, because I don't wanna hear it. Noisy , Loud S.O.B. Opened it up. Dead. Took off the covers, battery is split in half vertically. Mop up the mess. Do the OC and filter, remove battery carcass. Put in a spare 51R. Fired her up. Then I started workin the phone with Kohler. 4 years later, same old P.O.S. battery they installed is working. Never added a drop of distilled water to it. Still reading 13.3 floating volts.
 
Is that Porsche approved 0-40w approved for their air cooled engines or only for liquid cooled versions.
This is a thread from ‘04, but the data still likely applies since we are discussing air cooled Porsche engines.

Looks like oils meeting ACEA A3 spec are Porsche’s approved choice for their air cooled engines.

Edit: Meant to add that SuperCar meets and exceeds that spec.

 
Dude, you don't even know what you're talking about. The 0W-40 oil I use with Porsche A40 approval is not "too thin at extended use" nor is it degraded.

I don’t know anything about your vehicle - and don’t care what oil you use.

I would most likely use a 5W40 because it would be better. Maybe the 5w50 if I was running it hard.
 
Not to be dismissive or pedantic here, but what exactly is your motivation for wanting to change people’s oil preference in their OPE? Going over the hundreds of UOAs of various 0/5w-30/40 here in engines ranging from the Great White North down to the Southernmost tips of TX and FL aren’t showing any issues with running those. It’s been discussed by folks more knowledgeable on this subject than I that a 0/5W-40 will *typically* use a significantly higher quality base stock and VII than a narrower spread 15w-40.

I guess what I’m saying is, if you like your 15w-40, go ahead and use it. Not sure why you’re putting so much effort into trying to change everyone’s mind on it.
I have done a fair amount of research on ope engines - most engine failures are people using weak oil and not changing it.

This is an oil forum - expressing different opinions and exchanging information about oil related things is what people do here. If you don’t agree that is ok with me -

If I have hurt your feelings somehow I didn’t mean to-
 
I have done a fair amount of research on ope engines - most engine failures are people using weak oil and not changing it.

This is an oil forum - expressing different opinions and exchanging information about oil related things is what people do here. If you don’t agree that is ok with me -

If I have hurt your feelings somehow I didn’t mean to-
Your opinion was almost entirely “15w-40 or bust” in several posts. I was simply trying to figure out why you were telling others that running a 0/5W-30/40 was a horrible idea due to the lower W viscosities. It has zero to do with feelings. If you live in southern TX or southern FL, then sure, a 15W would likely suit you fine. Telling that to @repairman54 would get you laughed at. His equipment could be picked up clear off the ground by the recoil start cord and barely rotate the internals on a 15W oil.
 
We run 5w30 in ours, no problems. Engine will likely outlast the rest if the unit.
 
Your opinion was almost entirely “15w-40 or bust” in several posts. I was simply trying to figure out why you were telling others that running a 0/5W-30/40 was a horrible idea due to the lower W viscosities. It has zero to do with feelings. If you live in southern TX or southern FL, then sure, a 15W would likely suit you fine. Telling that to @repairman54 would get you laughed at. His equipment could be picked up clear off the ground by the recoil start cord and barely rotate the internals on a 15W oil.
Please don't try and twist my words

This is a cut and paste from my prior post in this thread. I bolded the parts that indicate when I support 15W40.

Where do you live?

Does it get below zero in the winter?

Over 100 in the summer?

I am in Texas so I would run 15W40 in the summer 5w30 in the winter.

15w40 > 5w30, 0w40, 10w30and 10w40 when it is burning hot outside.

I have no use for 0w anything unless it is freezing cold
.

I would not run a 0w or 5w anything when it is over 90 degrees.

You just spent $14k saving $15 on oil so you can use the same stuff all year does not seem like a good idea.


I talking about using 15W40 in a generator (not a car) in hot summer temps -

Just what value does a 0W anything bring to the table when it is >90 degrees outside, your power is out, no word about when it will come back on so you may have to run for 48 - 96 + hours straight?

I don't know who repairman is - he does have a snow mobile in his avatar so I will assume he is someplace cold - I grew up in South Dakota - lived in Iowa and Minnesota - I know all about winter. I have even ridden a snowmobile when it was -20.


I have never said running 0w or 5W whatever is bad when it is cold outside.

I even store my generator with 5W something - so if I need it and it is cold outside I am GTG - but if I need it when it is 100 degrees outside I would pick a time when I could swap it out for something more suited to the outside temp - like oh I don't know 15W40!
 
We run 5w30 in ours, no problems. Engine will likely outlast the rest if the unit.

Where do you live?

I think many generator failures are caused by a combo of dumb things - not just using "too light" of an oil.

I read a bunch of stuff from people in Florida running after a hurricane, high outside temps - and generators were failing.

1. They run near capacity of the unit
2. They don't change the oil.
3. They let the oil level get low.
4. They use a plain Jane 5W30 / whatever was available at Walmart.

You can do better by not over loading , change & check the oil no matter what oil you pick.

But - assuming you are running extended hours in hot summer temps why not move up and get some oil that will handle things better in this high stress environment?
 
Please don't try and twist my words

This is a cut and paste from my prior post in this thread. I bolded the parts that indicate when I support 15W40.

Where do you live?

Does it get below zero in the winter?

Over 100 in the summer?

I am in Texas so I would run 15W40 in the summer 5w30 in the winter.

15w40 > 5w30, 0w40, 10w30and 10w40 when it is burning hot outside.

I have no use for 0w anything unless it is freezing cold
.

I would not run a 0w or 5w anything when it is over 90 degrees.

You just spent $14k saving $15 on oil so you can use the same stuff all year does not seem like a good idea.


I talking about using 15W40 in a generator (not a car) in hot summer temps -

Just what value does a 0W anything bring to the table when it is >90 degrees outside, your power is out, no word about when it will come back on so you may have to run for 48 - 96 + hours straight?

I don't know who repairman is - he does have a snow mobile in his avatar so I will assume he is someplace cold - I grew up in South Dakota - lived in Iowa and Minnesota - I know all about winter. I have even ridden a snowmobile when it was -20.


I have never said running 0w or 5W whatever is bad when it is cold outside.

I even store my generator with 5W something - so if I need it and it is cold outside I am GTG - but if I need it when it is 100 degrees outside I would pick a time when I could swap it out for something more suited to the outside temp - like oh I don't know 15W40!
Yeah I’m not reading that mess.
 
I read that " mess" Panda. The manual on my gas Kohler 20 RESCA calls for synthetic 5W20 & an OE filter. Made up my mind to use the last of the 5W20, in about 6 weeks, when my back heals a bit from L3/4 disc replacement.( Last 5W20 OC , been using 5W20 since new in 2017)....... Next OC going with synthetic 5W30 & OE filter. I'm in NY. Avg temps range from 25-90. Machine exercises 20min a week. Fortunately, not too many power outages. Maybe 1 a year. Utility Comp did a good job trimming back trees, and my service line is underground for 1,000 ft. I have JUGS of synthetic 5W30 in stock. I have 2 old Toyota's that use that weight oil. I like you're " mess". Very helpful :)
 
Mobil 0W40 is robust and will stay a 40 weight (or possibly shear to a thick 30 weight) for the entire 50-100 hour interval. And you can use it year round and not have to worry about changing it before winter in colder northern states.

I’m a big fan of 15W40 as I live in Florida and have been without power for literally months of my life due to hurricanes. An SAE40, 10W40, 15W40, or 0W40, or 25W40 marine oil is ideal for generators that are ran for days on end at max load, 3600 rpm constant, in 90+ degree temps.

The manual in most of these engine manuals are written by a person that doesn’t really know oil. They won’t know what an ILSAC GF6-A 5W30 engine oil is (the majority of regular passenger car oils on the shelf) and why it’s not really ideal for a Florida/Texas summer in a generator.

I’m not here to really argue for or against 15W40. I will say, in my experience, ANY 40 weight, to include 0W40, offers a bit more margin for error over the ILSAC GF6-A 5W30 oils that almost everyone else is running in a generator.

Florida people use generators when it’s 90-95 degrees outside. Northern folks use generators during winter snow storms usually.

The power grid in Florida is very reliable and probably the most robust power grid in the entire country since the power companies have spent billions of dollars hardening it and replacing sections of it year after year after every incremental storm. Right outside my neighborhood, FPL has preemptively replaced every power pole with a much larger wooden power pole and every 4th pole or so is a now a concrete pole. The power to my neighborhood was buried to protect the lines. During Ian, a Cat4/5 storm, I lost power for only 2-3 hours I believe. Which is freaking impressive. As I was pulling my generator out of the garage, I suddenly saw the lights turn on in my garage. Had the generator handle in my hand as the power came back on. I did an about face and put the generator back in its storage location in the back of my garage. LOL.

Back to oil, southern folks should pick a Euro oil, and ACEA A3/B4 spec oil, or any 40 weight and call it good.
 
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