Stand by generator lube.

Messages
54
Location
Illinois, USA
We just installed a 20 KW standby gen system at our home. After 8 hrs. they require the break in oil be changed.They recommend 5/30 synthetic. The engine is a 36hp twin air cooled engine. My question is, on my previous smaller 16 hp 7.5 kw unit I have tried M1 5/30 and 20/50. The 5/30 needs to be added at a significantly more frequent rate than the 20/50. This new setup runs once a week, automatically, for 10 mins to test the system and lube the engine. Since we can have outages that last 5 days what oil coukd I use that will not run through the engine as fast as 5/30 but not be as viscous in the dead of winter as 20/50?
 
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Messages
1,676
Location
Waldorf, Maryland
Go with the specified 5W-30 oil. I use synthetic 5W-30 in my 11 HP riding lawn mower, rarely do I have to add oil. Most mower/tractor air cooled engines recommend 5W-30 synthetic oil. Even if you do have to add oil, so what, it is not that expensive. The specified oil will probably let the engine last longer. Did you use synthetic on your 16 hp unit right after the break in oil, or did you use regular oil for a while?
 
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Messages
14,843
Location
Illinois
A friend has a Generac repair business. He uses M1 5-30 in all of his PMs which includes engines like yours. His normall OC rate is once a year and has never mentioned oil use. I would not use a 20-50 oil in one of these units. Also this should have been posted in the small engine section.
 
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Messages
5,123
Location
Pittsburgh,PA U.S.A.
I use GC in my two portable gensets (Coleman Powermate with Tecumseh 10 HP HM-100, and Generac iX2000) and also use GC in our 2001 Impala 3.4L with 68,900 miles on it. I use to use M1 5W-30 in the Impala, until it started to consume oil at 1 Qt per 1000 miles. I switcht to GC and ran 5K miles without the oil falling below the full mark, and did not have to add any oil. I broke the Coleman in with Castrol straight 30 weight, and after I put GC in it, my brother said it was much easier to pull start on a cool day. GC is Castrol Edge 0W-30 in the black bottle and it will say European Formula on the front. Some of the reports show it to protect better than 5W-30 and 10W-30. It holds up in hot temperatures and it flows good in cold. You can find it at Pep-Boys.
 
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Messages
5,123
Location
Pittsburgh,PA U.S.A.
LILGUY, where in the US are you located, NORTH, SOUTH? I keep two bottles of M1 Vtwin 20W-50 for hot summer days for the Coleman genset with the Tecumseh HM-100, but would not try to use an oil that thick if the ambient were below 75F.
 

LILGUY

Thread starter
Messages
54
Location
Illinois, USA
I live NW of Chicago. I had a period this summer when the power was out Monday morning to Friday night.Used 5/30 but had to add oil often during 24 hour fuel cycle. Switched to Vtwin and 48 hours continuous no oil add.
 
Messages
555
Location
Tennessee
LILGUY, You have been given good advice. Before I sold my 15kw air cooled, Generac, I too, found that it would consume Mobil 1 5W30 faster than most oils. I don't care what the Generac book (or the service techs recommend). They miss the boat on this one. We had Michigan winter & summer outages of up to 50 hours. After 50 hours of continuous operating, my generator was almost out of oil. Other Generac owners will tell you, the unit will automatically shut off (to prevent damage), if the oil level drops further. This is usually after 2 days. I had much better oil consumption performance with the thicker Castrol 0W30. I am sure you could run Mobil 1 0W40 for over 5 days, year round, without any worries. Also straight 30 wt works great during the summer. It's cheap and it's easy to find.
 

LILGUY

Thread starter
Messages
54
Location
Illinois, USA
Thanks all. I'd prefer one weight year round.What about AMSOIL? I was really caught off guard by the rate the 16hp used M1 5/30. Got into the rhythm checking oil several times a 24 hr period. Tended to keep me sleeping light worrying about low oil at 3 AM. The Generac is 36 hp. and holds 1.9 qts.Thats less than the smaller gens hold so I'd like an oil that does not get used up fast. May be an experiment I'll have to run with different oils.
 
Messages
171
Location
VA
I have Amsoil ASE in my Generac 17KW. It has held up well and still clean, but has only run for weekly tests and thirty minutes each month under load. I had Amsoil AAF in the unit previously, which seemed to work well. If you can get a longer oil filter on the unit, you will gain some oil capacity as well. I know the units call for 5W-30, but I have been served well by the SAE 30 Amsoil in it now and the previous run of 0W-40 Amsoil.
 
Messages
1,841
Location
.
I used RTS 5W40 in my HF Chonda 13HP which ran for 200 hours straight two summers ago with zero consumption. The oil that was in there at the time sat for a year. I did a UOA on it and it came back better than average for a small engine. I have used this generator in sub zero weather with RTS 5W40 with easy starts. For my snowblower (which nobody asked about frown ) I use Amsoil 0W30.
 
Messages
4,942
Location
Billings, MT
I would use Red Line 5w-30. It contains no VII's so it isn't going to shear, it will flow well when cold, and contains a lot of moly that would help protect the engine until it gets up to temp.
 
Messages
14,843
Location
Illinois
Originally Posted By: Best F100
LILGUY, You have been given good advice. Before I sold my 15kw air cooled, Generac, I too, found that it would consume Mobil 1 5W30 faster than most oils. I don't care what the Generac book (or the service techs recommend). They miss the boat on this one. We had Michigan winter & summer outages of up to 50 hours. After 50 hours of continuous operating, my generator was almost out of oil. Other Generac owners will tell you, the unit will automatically shut off (to prevent damage), if the oil level drops further. This is usually after 2 days. I had much better oil consumption performance with the thicker Castrol 0W30. I am sure you could run Mobil 1 0W40 for over 5 days, year round, without any worries. Also straight 30 wt works great during the summer. It's cheap and it's easy to find.
You may have some sort of defect in your engine if it consumes 5-30 oil. My Generac friend has had to replace two engines recently for various problems. These generators have engine problems he sees all the time. Actually these engines are designed to shut down with most of the oil still in the engine. It doesn't take much oil loss for this to happen. Your two day comment doesn't make any sence unless that system failed as well.
 
Messages
300
Location
SE Michigan
Originally Posted By: Best F100
We had Michigan winter & summer outages of up to 50 hours.
Sounds familiar. All we need around here to have a power outage is a stiff breeze. When I first got my generator, I was worried about how long it would sit between uses and if there would be rust problems, in reality it has not been an issue... +1 on the Mobil 1 0W40. It has more Zinc/Phosphorus than most other oils and should be fine all year round for a Great Lakes climate, and it's easy to find.
 
Messages
777
Location
Herndon, VA
How about this for a recommendation: Amsoil Z-Rod 10W-30 (ZRT). It has extra Zinc for wear protection, added rust-inhibitors to prevent rust when the engine is not run for extended periods, and unlike Amsoil ASE, it has extensive friction modifiers which should improve fuel usage. It's a heavy 30 weight oil, which should help oil consumption, but still meets 30 weight specifications so you are still adhering pretty closely to manufacturer's specs. I will be starting to use this oil in all my small engines once the grass-cutting season is done, with the exception of snow removing equipment, which I run when temperatures can be in the teens and twenties, although ZRT would probably be fine then, too.
 
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