Originally Posted By: rectifier
A bit puzzled as to what to do with my new inverter generator.
I'm a farmer, and go through the expected "plenty" of oil. I have standardized on two oils at the farm:
- Walmart Tune-it (Super tech) 5W-30 for gas
- Rotella 15W-40 for diesel
I also run 0W-40 synth in my winter feeding/snowplow tractor, but it's special.
The genset is a little 3500W 150cc model with an air-cooled Chinese motor. Manual wants straight 30W or 10W-30 but motor is stamped 15W-30.
The 15W is throwing me for a loop as I only ever see it on diesel oils.
It's a backup which may have to run in temps anywhere from -30C - +30C. However, it's stored indoors for easy starting in winter.
I threw 5W-30 in to get going as it's still cold out but am wondering if the 15W-40 is better. Definitely better oil. But is it too thick to splash well? And will it be a bear if my wife has to start it?
As an inverter most hours will be spent at idle or near it with occasional bursts of full throttle to start a motor. Plan to do weekly test runs as well as sometimes use it with my pancake compressor for nailing.
You have two general concerns:
1) getting it started
2) running temps
No. 1 is already taken care of; it will start easily when stored indoors. That also means that a syn is not needed as you don't have to fight really cold sump temps to pull it over.
No. 2 is a bigger issue. You're going to have to decide if you want one year-round lube or OCI winter/summer. I think you'll find that multi OCIs are a big PITB. The real problem is the RUNNING temp of the sump. If you are going to operate outdoors in winter, an air-cooled engine will struggle to come up to temp, especially in the sump. A 15w-40 will work, but it's not optimum. A 30 grade would be much better. I would recommend 10w-30 year round.
First-hand experience:
I had my two gen's running last year in temps from a high of zero F to a low of -17 F for almost four straight days! We lost power in the blizzard and I had to rely on the two gens to power my home. Both are air cooled; one is a "modern" OHV 8hp Subaru, the other an "ol skool" flathead Tecumseh 10HP. I run 5w-30 syn in both, because they sit in unheated storage when not in use. They were a little tough to start, but not terrible; it took about 3 pulls for the OHV and 5 for the f.h. The smaller one ran non-stop for 4 days. The larger one only powered our well-pump as needed (about once a day for an hour for showers, dishwasher, fill toilet tanks, etc). The one that ran non-stop never really got up to full temp. After each 24 hour period, I did a shutdown to check oil level. While the level was fine, the oil was not hot by any means; it was "tepid" and could easily be touched by bare skin. The larger 10hp engine was the same way, even after running the 1hp well pump under near full load for an hour! Because of the cold, the sumps never came to full temp; not even close. I would estimate that they were below 80F, because I could put my finger in the sump hole and hold it there indefinitely; they were "warm" but nowhere near what would be considered "normal" for an engine sump.
My point is this; I don't think 15w-40 is a good choice unless you intend to OCI seasonally. And that is a very big pain-in-the-posterior to do; you'll find it tedious after a few times. Better to pick a lube that would work well year round. Because of your inside storage, 10w-30 would do well for every season. And don't worry; a 10w-30 is PLENTY able to handle the opposite summer season heat. You won't "need" a 40 grade for summer.
Although you didn't ask, I'm also going to add this ...
Always excercise your gens under electrical load at least 3 or 4 times a year. Most any manual states to do it monthly, but I think that is overkill. About once a season is fine. Here's why:
the magnetic field in the gen head can, over extremely long periods of non-use, actually loose it's field-effect and won't excite; hence - no power. I've actually had to help a buddy out with his "dead" gen head. The motor was stored well with a proper carb drain; it ran fine, but electrical head was DOA and would not produce AC. There is a trick one can do to "jump start" the field, but it takes a 12V battery and some abilility to know what you're doing. And who wants to mess with that when you're probably in the middle of an emergency already, anyway? Just do yourself a favor and start the genny up at least 3 times a year, AND RUN IT UNDER A LOAD TO EXCITE THE STATOR/ROTOR FIELD EFFECT! You MUST run it under a load to keep the field magnets active.
Is this a Boily by any chance? Doesn't really matter to my answer; was just curious.
