generator oil recommendations

Status
Not open for further replies.
Joined
Nov 29, 2009
Messages
7,216
so I have a gx390 engine on my Honda generator and they recommend 10w30 oil in it all the way up to 100 degrees. I hear on here how people burn up there generators using 30 weight oils when it's hot out and under heavy load. I'm not sure what some of you guys mean by that. As in the oil failed and got too thin or it just ran out of oil. I think most people go out and buy a cheap Chinese generator which holds little oil and then neglect to check the oil level frequently when it's brand new and then it throws a rod.
 
I'd put in Rotella 10w-30.
thumbsup2.gif
 
Amsoil ASE 30/10w30 and be running VPracing small engine fuel particularly for shutdown and storage.
 
I have used 10w30 in these Florida nights camping and watched my muffler glow a orange on a Briggs Stratton. I switched to 30wt after that. I would also 2and 15w40, it is a excellent oil that heat will not kill.
 
Originally Posted By: edwardh1
keep in mind if you need to run it on a winter day during an ice storm. 30 w may be bad starting then


How many ice storms does he have in Houston?

OP, 5W40 is the bees knees in generators in the summer. 15W40 if you prefer a conventional.

image9.jpg
 
In addition to the oil viscosity how many burnt up generatore were run without ever having the oil checked or changed?
 
Cool story, bro.

Originally Posted By: motor_oil_madman
so I have a gx390 engine on my Honda generator and they recommend 10w30 oil in it all the way up to 100 degrees. I hear on here how people burn up there generators using 30 weight oils when it's hot out and under heavy load. I'm not sure what some of you guys mean by that. As in the oil failed and got too thin or it just ran out of oil. I think most people go out and buy a cheap Chinese generator which holds little oil and then neglect to check the oil level frequently when it's brand new and then it throws a rod.
 
Also, don't count on the low oil shutdown.

My son was given a 32 HP V/2 welder/generator because it had an oil leak and the welder friend that gave it to him did not want to fool with it. Son started it to show me how well it ran and then after he shut it off I checked the oil level. One CUP of oil was all it had in it and it still stared even with a low oil shutdown feature.
 
All of our gas Onan 5.5 and 7kw run 15-40 all year long. In one of the routinely colder spots in the US. Saranac Lake NY. Not ideal but I use what the company gives me.
 
I have a Generac 16kw whole house generator with the GT-990 engine. It's 9 years old and I've used both 5w-30 (OM recommendation) and 10w-30. With Amsoil 10w-30, it uses measurably less oil than it did with PP and QSUD 5w-30. Of course, it's different than an RV generator. I'd say go by your OM and your climate.
 
Originally Posted By: motor_oil_madman
so I have a gx390 engine on my Honda generator and they recommend 10w30 oil in it all the way up to 100 degrees.

If Honda recommends that, then why not run with it? On the other hand, if you are concerned about prolonged running above 100 degrees F, a synthetic 5w40 or 10w40 might be in order. It seems from the manuals available online that Honda doesn't really advise what to do above 104 degrees F. If it were me and the possibility of running flat out for hours on end above even 90 degrees F were in the cards, then there would be Xw40 in the motor.
 
The reason for so many generator failures here in Florida (post hurricanes) was not that the outside temperature was over 100, it was hot AND humid though. Nor was it that the oil level ran low. It was the fact that people place the generator next to the house, in stagnant air, and used the generator to power the water heater and air conditioners. Hours and hours of full load gets the oil temperature up to absurd numbers. (this is quite unlike lawnmower or pressure washer duty, where the engine load is not 100% for hours on end)

5W-30 conventional oil is not an ideal choice when oil temps are near 300 degrees F. The result is predictable, and nearly always the same. The connecting rod is starved for oil film, metal to metal contact occurs and eventually, the connecting rod seizes to the crankshaft and the rod breaks.

I had 2 Honda engine failures (water pumps, used to de-water my property) due to this. I used the recommended 5W-30 oil. My third water pump gets Mobil 1 TDT oil.

If your generator is not used to heat water, or power a 4 ton air conditioner and it's operated under modest loads, the standard oil will be just fine.

If you choose to abuse your equipment, I suggest a more robust oil.
 
Originally Posted By: Cujet
The reason for so many generator failures here in Florida (post hurricanes) was not that the outside temperature was over 100, it was hot AND humid though. Nor was it that the oil level ran low. It was the fact that people place the generator next to the house, in stagnant air, and used the generator to power the water heater and air conditioners. Hours and hours of full load gets the oil temperature up to absurd numbers. (this is quite unlike lawnmower or pressure washer duty, where the engine load is not 100% for hours on end)

5W-30 conventional oil is not an ideal choice when oil temps are near 300 degrees F. The result is predictable, and nearly always the same. The connecting rod is starved for oil film, metal to metal contact occurs and eventually, the connecting rod seizes to the crankshaft and the rod breaks.

I had 2 Honda engine failures (water pumps, used to de-water my property) due to this. I used the recommended 5W-30 oil. My third water pump gets Mobil 1 TDT oil.

If your generator is not used to heat water, or power a 4 ton air conditioner and it's operated under modest loads, the standard oil will be just fine.

If you choose to abuse your equipment, I suggest a more robust oil.


I could run delo 400 15w40, but what about when it's not 100 degrees outside? My concern was it being a splash lubricated engine. Like for example right now it's only 75 degrees outside. Will the delo be ok on a 50 degree day?
 
I run a Yamaha EF2000is portable as an auxiliary power supply on my semi truck when the truck is stopped and shut off for several hours. I use it year round, but more frequently in the winter. I use the Amsoil 10w30/30w in it year round. And the generator runs inside a specially designed aluminum box on the side rail of the truck. The box has removable openings on the side and rear. I have run it in that box at temp spreads of -25F to 105F. All on the Amsoil 10w30/30w stuff. Bought it about 10 months ago and now have 325 hours on it and is just like the day I bought it.

The Amsoil stuff is a straight weight 30, but satisfies a 10w30 flow rating with no VI. All I know, is that my JD Zero turn mower that has to mow 2 acres of yard, and my little Yamaha EF2000 really do well on this stuff.
 
For 5500W portable, homeowner generators, Generac is specing synthetic 5W-30 for all temperatures, and Champion is specifying 10W30 for all temps above 0 degF. Champion only allows 5W30 at temps below 30 degF. Both are splash lubricated.
 
Last edited:
I use M1 10-30 in all my OPE, including my 5KW gen. Also a friend is a Gernerac tech, and he uses M1 5-30 in all his PM checks, per Generac schooling. He has never had a problem.
 
Status
Not open for further replies.
Back
Top