honda gx390 generator oil

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The motor guy

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Honda recommends 10w30, but I've heard from a couple members on here that running a 30 weight oil is a bad idea on a heavily loaded generator in the summer. Not sure if this is just another cover all the bases type of oil weight? Any reason why a 15w40 couldn't be used in it?
 
Think for a moment about the stress this engine is under when heavily loaded on a hot summer day...

Now, realize the only thing keeping it alive is one quart of oil.
 
Originally Posted By: Ramblejam
Think for a moment about the stress this engine is under when heavily loaded on a hot summer day...

Now, realize the only thing keeping it alive is one quart of oil.


Why do they recommend such thin oil then?
 
"Thin" is relative, and highly subjective.

If you do the proper maintenance, and keep it running in good condition, then I'd be fine with 10w-30.

The issue here is that people never bother to do an initial oil change at 20 hours, never change again at prescribed intervals, never do any other maintenance, and run the cheapest oil they can grab.
 
I have been using Power RS Racing 4T Motor Oil for quite awhile on all my generators and 4wheeler and it has worked great actually stopped some smoking on my 4 wheeler a real good product. I even use it in my snow blower all with great results.
 
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My 16kw Generac specs 5w-30 synthetic. It's 9 years old and I find that it consumes less oil when I use Amsoil 10w-30 small engine oil. And I've got no skin in the Amsoil game. It just seems to work well in my generator.
 
I bought some semi synthetic diesel oil 10w30 for my GX390 and GX160. Anything multigrade 10w30 or 15w40 is good
 
"Honda recommends 10w30, but I've heard from a couple members on here that running a 30 weight oil is a bad idea"

I guess Bob's members are much more intelligent than Honda's engineers.
 
I'm sure Honda's recomendation is a little more reliable than what some members recomend on here
 
Originally Posted By: Ramblejam
"Thin" is relative, and highly subjective.

If you do the proper maintenance, and keep it running in good condition, then I'd be fine with 10w-30.

The issue here is that people never bother to do an initial oil change at 20 hours, never change again at prescribed intervals, never do any other maintenance, and run the cheapest oil they can grab.


This is probably over 90% of the problem. Get any xw30 full synthetic you have something better than the cheap 10w30.
 
To be specific about Honda's GX390 oil recommendations, they claim 10W-30 for general use. Straight 30 for temps over 10C (50f) And for LPG GX390's they specifically prohibit multi grade oils and simply require straight 30.

As I continue to say, post hurricane generator operation here in South Florida really "taxed" many generators. And while few of the failures were Honda engines, there were some. I had 2 Honda water pump (for de-watering my 2 acre lot) engines fail on Penzoil Multigrade oil. Honda was good enough to warranty them. The second one, they really complained about.

I now use Mobil 1, 5W-40 in everything. It's a robust oil, with a fantastic additive package, and it's performance under very high temperature conditions is superb. (HTHS 3.8)

Note: My Kawasaki powered Snapper mower regularly had oil temperatures North of 260 degrees F ! And, that's normal.

Many of the generator failures (local to me) were caused by people heating water (4500W) for 3 to 4 hours. This was often at the absolute limit of the typical homeowner generator. Parked next to the garage, the stagnant air would simply recirculate, the oil temp would climb, and the connecting rod large end would seize on the cranshaft. Leading to catastrophic failure. Honda engines are not immune to abuse, as I found out.
 
Originally Posted By: 901Memphis
10w30 is fine, especially if it's Mobil 1 High Mileage 10W30


or Mobil 1 EP 10w30.

Add an ounce of LM Ceratec to it on every oil change
 
I've gone with a 5W-40 oil for my Chicago Electric (HF) generator. The manual specs 10W30 SH/SJ, and I suppose it's OK for intermittent use. For prolonged use, say a full tank's worth of fuel; I can't get over the need for far more robust oil. I live in a 4 season climate, and need the ability to get a 1-2 pull start in temps from -10F to 100F. Since you're in Houston, I'd suggest that you look at 10W30 or 15W40 HDEO because you don't have winter. If you're not comfortable with that, then 5W40 is a fine choice.

A shout out to my Brothers and Sisters of the 3d Cavalry Regiment-BRAVE RIFLES!!!!!!!!!!
 
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Originally Posted By: Cujet
To be specific about Honda's GX390 oil recommendations, they claim 10W-30 for general use. Straight 30 for temps over 10C (50f) And for LPG GX390's they specifically prohibit multi grade oils and simply require straight 30.

As I continue to say, post hurricane generator operation here in South Florida really "taxed" many generators. And while few of the failures were Honda engines, there were some. I had 2 Honda water pump (for de-watering my 2 acre lot) engines fail on Penzoil Multigrade oil. Honda was good enough to warranty them. The second one, they really complained about.

I'm going to go ahead and use delo 400 15w40 in everything. Rarely does it get below 40 degrees, so I'm assuming the oil will be fine. If you can run a 30 weight then you can run a 15w40 I'm assuming.

I now use Mobil 1, 5W-40 in everything. It's a robust oil, with a fantastic additive package, and it's performance under very high temperature conditions is superb. (HTHS 3.8)

Note: My Kawasaki powered Snapper mower regularly had oil temperatures North of 260 degrees F ! And, that's normal.

Many of the generator failures (local to me) were caused by people heating water (4500W) for 3 to 4 hours. This was often at the absolute limit of the typical homeowner generator. Parked next to the garage, the stagnant air would simply recirculate, the oil temp would climb, and the connecting rod large end would seize on the cranshaft. Leading to catastrophic failure. Honda engines are not immune to abuse, as I found out.
 
Originally Posted By: Cujet
To be specific about Honda's GX390 oil recommendations, they claim 10W-30 for general use. Straight 30 for temps over 10C (50f) And for LPG GX390's they specifically prohibit multi grade oils and simply require straight 30.

As I continue to say, post hurricane generator operation here in South Florida really "taxed" many generators. And while few of the failures were Honda engines, there were some. I had 2 Honda water pump (for de-watering my 2 acre lot) engines fail on Penzoil Multigrade oil. Honda was good enough to warranty them. The second one, they really complained about.

I now use Mobil 1, 5W-40 in everything. It's a robust oil, with a fantastic additive package, and it's performance under very high temperature conditions is superb. (HTHS 3.8)

Note: My Kawasaki powered Snapper mower regularly had oil temperatures North of 260 degrees F ! And, that's normal.

Many of the generator failures (local to me) were caused by people heating water (4500W) for 3 to 4 hours. This was often at the absolute limit of the typical homeowner generator. Parked next to the garage, the stagnant air would simply recirculate, the oil temp would climb, and the connecting rod large end would seize on the cranshaft. Leading to catastrophic failure. Honda engines are not immune to abuse, as I found out.
I would also wonder if they ever changed the original oil or checked the level after several hours of operation.
 
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