Have 5000 watt Honda generator about 30 years old. What should I use for oil? I think it calls for 30 weight non-detergent. I was thinking reg 10-30 or Mobil 1. This is setup to run and shut off Automatically on power loss/restore. This might be the 2nd oil change in it's life! Gary
10w-30 will do . 30wt is still available but in limited varieties and I've not seen a synthetic 30wt widely available. I recommend synthetic over Dino in just about every case, if this unit will be called upon to start automatically in freezing temps, then 10w30 synthetic is a great choice.
Get alittle seafoam engine treatment and run some in the crankcase just before you change the oil. Seafoam cleans up any sludge laying in the bottom of the motor. If you put some in the fuel, it cleans up the carb as well. Great stuff.
You guys are the only ones I've heard talk highly of seafoam. Likely that the folks I talked to were trying to fix a hole in a piston or some other thing. It seems some people think you can repair catastrophic damage with a bottle of goo.
I'll give it a try if it ever comes up, which I'm sure it will. I trust you yahoos on this subject more than my real life yahoos.