Oil for Generator on Propane???

[BigJohn]

About 7 years ago, I purchased a tri-fuel carburetor for my Honda powered, 6,000 watt generator, and plumbed it to run off the natural gas valve which feeds my BBQ grill on the back of my house. In my research, I read somewhere that if you run a combustion gas engine on either natural gas or propane, you should feed the engine sump, straight grade 30wt. .... something about 5w30's breaking down way too fast.

Anyway, I just upgraded to a 12,500 watt genset, designed from the factory to run on Propane and I wonder if there is still guidance to use straight grade 30wt? (The genset is ordered and won't arrive until next Friday.) My concern is the elevation and temps where I now live, 8,000 ft and easily zero degree temps in the Winter. Seems I would be much better off with a 5w30 or even a 0w30. This new genset is powered by a commercial Honda built, 14hp engine.

Interesting side note.... I did some searching and the Generac website for whole house units that run on Propane 20, 30... 50kw units..... They recommend 0w20 for their engines. WOW!

Predictably, you guys might guess that I would like to use Rotella T5 10w30.

........

 

[fantastic]

About 7 years ago, I purchased a tri-fuel carburetor for my Honda powered, 6,000 watt generator, and plumbed it to run off the natural gas valve which feeds my BBQ grill on the back of my house. In my research, I read somewhere that if you run a combustion gas engine on either natural gas or propane, you should feed the engine sump, straight grade 30wt. .... something about 5w30's breaking down way too fast.

That sounds odd about a grade.

Anyway, I just upgraded to a 12,500 watt genset, designed from the factory to run on Propane and I wonder if there is still guidance to use straight grade 30wt? (The genset is ordered and won't arrive until next Friday.) My concern is the elevation and temps where I now live, 8,000 ft and easily zero degree temps in the Winter. Seems I would be much better off with a 5w30 or even a 0w30. This new genset is powered by a commercial Honda built, 14hp engine.

Propane fuel can make oil more acidic. That's when oil sampling you'll want to use TAN. But certainly no reason not to use a multi-grade oil. Just like you suggested, I & many others here would recommend a 0w or 5w oil. I always use a low winter number in any Generator I have.

Interesting side note.... I did some searching and the Generac website for whole house units that run on Propane 20, 30... 50kw units..... They recommend 0w20 for their engines. WOW!

Predictably, you guys might guess that I would like to use Rotella T5 10w30.

There are many options for you & that T5 should work great.

 

[thastinger]

About 7 years ago, I purchased a tri-fuel carburetor for my Honda powered, 6,000 watt generator, and plumbed it to run off the natural gas valve which feeds my BBQ grill on the back of my house. In my research, I read somewhere that if you run a combustion gas engine on either natural gas or propane, you should feed the engine sump, straight grade 30wt. .... something about 5w30's breaking down way too fast.

Anyway, I just upgraded to a 12,500 watt genset, designed from the factory to run on Propane and I wonder if there is still guidance to use straight grade 30wt? (The genset is ordered and won't arrive until next Friday.) My concern is the elevation and temps where I now live, 8,000 ft and easily zero degree temps in the Winter. Seems I would be much better off with a 5w30 or even a 0w30. This new genset is powered by a commercial Honda built, 14hp engine.

Interesting side note.... I did some searching and the Generac website for whole house units that run on Propane 20, 30... 50kw units..... They recommend 0w20 for their engines. WOW!

Predictably, you guys might guess that I would like to use Rotella T5 10w30.

........

Kohler 10w-30. Good oil that they recommend for their propane and NG gensets. You can find some VOA of it on here.

 

[Wireman1987]

Just follow the owners manual recommendation for climate and oil viscosity use. No reason to overthink this anything from Walmart or local auto parts store will work. I would suggest a 5W30 full synthetic year round.

 

[Chris142]

I delivered propane about 23 years ago. I drove a Ford F800 with a 429 Ford industrial engine in it. They also had gm trucks with 454's in them. They all got Chevron 10w-40.

 

[BigJohn]

Found a PDF of the owners manual online for my exact model and there is no differentiation whether running with gas or Propane. They say to follow this chart.

 

[Wireman1987]

Found a PDF of the owners manual online for my exact model and there is no differentiation whether running with gas or Propane. They say to follow this chart.

View attachment 304345

you can run the snot out of a 5W30 synthetic

 

[MurkyAsparagus]

These generator engines are picky at all. Oil viscosity would be dependent upon your environment/climate. In general, I would pick any 5w30 or 5w40 Euro or HDEO oil. You cannot go wrong with M1 Delvac ESP 5w40 or really any full synthetic HDEO.

 

[repairman54]

5-30w full synth. will be fine. I easily see -10f winter temps., summer record high here is only 93f. On my 2nd Generac in a new house. Old house no issues. 11k units.
Both units have a cold weather kit on them. Generac kit is a heater sleeve on the oil filter and a battery warming pad.
Only way I would use a 0 oil would be above the arctic circle with super low negative temps. As said a good 5-30w synth. will give good protection over a wide range of temperatures.

 

[Sam_Julier]

Our 17kw Generac 2 cylinder air cooled engine ran 7 hours yesterday on Mobil 1 5W-30 EP. No oil consumption.

It’s my go to oil for this unit.

 

[Japanese]

Found a PDF of the owners manual online for my exact model and there is no differentiation whether running with gas or Propane.

I would run synthetic 10W-30 and possibly non resource conserving.
Also keep in mind that although propane has lower BTU than gasoline, the first one burns slower and that makes the engine runs hotter - when exhaust valves open the propane is still burning. That also make the EGT higher too. Some people have issues with burned valves running on propane.

It's interesting on the oil chart why the 5W-30 non synthetic is cut 20°F?

 

[Tom NJ]

I just had a Generac standby 26kW whole house propane generator installed last week. The owner's manual sets no requirements for the oil! It just says that "All Generac oil kits meet minimum API Service Class SJ, SL or better" and "It is recommended to use Generac's proprietary 5W-20 gaseous engine oil for continuous use".

Their website, however, recommends "Generac 5W-20 full synthetic oil for all home standby generators, no matter the temperature", but also allows a straight 30, a 10W-30, and a synthetic 5W-30 for specific temperature ranges. All recommendations, no requirements.

Generac Oil Recommendations

Apparently the engine is not very sensitive to viscosity or API Service Class. Mine will get Mobil 1 5W-30 API SQ after the 25 hour break-in.

 

[JavierH19]

Normally i'd say you'd be best off running cheap supertech and dumping that out earlier than what the manual says but that's a bit cold. That engine is air cooled and always blowing cold air on itself and probably doesn't get hot so a 20 grade could work in the winter. In the summer with much higher ambient temps i'd rather use 30 grade unless power outages are extremley rare so keeping a 20 grade for occasional test runs is fine.

Since it's splash lubricated an oil with a lower kv40 would be better in such low temps. A low viscosity 30 grade with a 0w would be what i'd use for year round use. M1 afe 0w-30 would be thinner and easier to sling in the winter cold starts than esp 0w-30 or ST 5w-30.