Resting a generator

[Jerry1]

We had an ice storm last night which took out a lot of power in the area. They’re hoping to get everyone back online by Sunday. So a best case scenario is that the generator will need to run for four days, maybe more. I was reading about how long the generator should run continuously and there were some articles that said you should shut down the generator, let it cool off and check the oil every day.

I’m a bit nervous about shutting it down because of the potential that it might not restart. To me, it seems like letting it run would be better, but I don’t have a good sense of the oil usage. I change the oil and check it regularly but I’ve never ran it this length of time. I’m sure it has a low pressure sensor that should shut it down if it gets low, but that seems like it would damage the engine. FWIW, my generator is a natural gas powered 4 cylinder liquid cooled engine.

There’s also the option of just running it a few hours each day just to keep the house warm and the refrigerator cold, etc.

What would you do?

 

[Car-Guy]

Running low on oil will ruin your day (and your generator). Mine are gasoline powered so I need to shut them down when a refill is necessary and I can check the oil then. I probably run mine at least a week "overall" between oil changes (probably more). OTOH, I rarely need to add oil, so there is that to consider... YMMV

Also, I never bought into the idea of shutting them down "just" to let them cool off. They don't need a rest. PM yes, rest no.

 

[Lewis Clark]

What would you do?

I'd see what the manual recommends. If that fails, I'd call the manufacturer and ask for their recommendation.

 

[skyking1]

^ that.
If you have not made a 4 day run with it then you are correct in not knowing the oil usage.
The manufacturer will have the guidelines for you. They don't want to burn up engines either.
I would suggest that whatever you do, shut it down during the day so if there is the slightest hiccup you at least have some daylight to get it going again.

 

[Jerry1]

Thanks. I chatted online with them. There was nothing in the manual. However, they recommended shutting down and checking the oil every 24 hours.

 

[RobbieB]

I don't think there would be any problem with re-starting, especially with nat gas. No vapor locks, no over temp as liquid cooled. Yeah if they say shut it down and check oil every 24 then that is what I would do.

 

[njhowie]

Your owners manual will indicate how many hours of usage between oil changes. But, keep in mind, circumstances and usage vary. So you may well be able to go much longer than the recommended change interval without any negative effects. I'm also of the belief that those recommended intervals are fairly conservative.

During hurricane Sandy, we ran our industrial Cummins Onan generator for 7 or 8 days straight. I believe the change interval recommended is around 50 hours. No shutdowns, no oil checks, just kept running and running and topping off the gas tank every night before going to sleep. Afterwards, I gave it a good oil and filter change. We've had the generator for over 20 years and it still runs wonderfully.

 

[Jerry1]

Yeah, the manual says to change the oil after 30 hours. But, that’s in the maintenance section where it says to run it for a half hour every week. So, on that schedule 30 is about every year. I’m not going to change the oil basically every day. Though I will change the oil after this event once we have a somewhat warm day - say 40+ degrees.

 

[RobbieB]

Perhaps the 30 hours is the first "break-in" oil change? I can't see a 4 cylinder, water cooled, natural gas powered engine needing more than the usual once a year or 200 hours plan. Especially natural gas the cleanest (after hydrogen) fuel available.

 

[Walt34]

Does the engine have an oil filter? That makes a huge difference in oil change intervals, usually it doubles it over a non-filtered oil sump. Also if you haven't already, use full synthetic oil as that can go longer than regular oil.

The size of the oil capacity matters too.

As far as "resting" it goes, no. It's a machine. It doesn't care. In fact it's probably better to run continuously since that makes for fewer thermal cycles. When the engine first starts when cold and as it's warming up is when the majority of the engine wear takes place.

 

[d.davis]

I'd be surprised if the generator doesn't have a low oil shutdown. If it's a new generator it might use more oil for break-in but if you got more than 10 hours on it it's probably stable.
If you shut it down at 24 hours to measure the oil and there's no observable loss let it run the full four days.

Sent from my moto g power using Early Retirement Forum mobile app

 

[rk911]

we have an air-cooled, natural gas whole-house stand-by generator. a few years back we had a 80+ hour power outage (ice storm). our genny ran flawlessly the entire time. i did stop it once or twice to check the oil level. the PM schedule calls for an oil change every 100-hrs or 12-months. this is the best upgrade to the house we've ever done.

 

[street]

I personally wouldn't run it all the time while power is off. I would use it a few hours when needing it than shut it down. I would use it if it were needed not continuously. A good time to sit down with some great books and enjoy life without power.

When we are out of power, I enjoy not having all the high tech and luxury we are accustomed too.

 

[RobbieB]

Yeah, we've got the led lantern, 400 watt-hour UPS on the living room leds (uses 12 watts) and as long as you have a lantern to carry when you head to the head and a place to sit and read...

Life is good -

But when the food is in danger of spoiling or you need to cook some food, Crank it Up!

 

[Jerry1]

Um, that sounds great but not for me. I’m having withdrawals. No tv except for the antenna, which sucks, and no internet except through my phone. The internet is crap because the system is overloaded right now plus we’ve never got a great signal while at my house. At least I can play some of my games, but even they need to check into the mothership through the internet to operate correctly. Gonna have to get out and do something tomorrow. Problem is, the whole area got hammered.

One thing is for certain though, I’m very grateful that we have the generator which means we have heat and not having to deal with food going bad.

 

[street]

Um, that sounds great but not for me. I’m having withdrawals. No tv except for the antenna, which sucks, and no internet except through my phone. The internet is crap because the system is overloaded right now plus we’ve never got a great signal while at my house. At least I can play some of my games, but even they need to check into the mothership through the internet to operate correctly. Gonna have to get out and do something tomorrow. Problem is, the whole area got hammered.

One thing is for certain though, I’m very grateful that we have the generator which means we have heat and not having to deal with food going bad.

TV I would never have to have, or would I miss it, but my wife has stuff she likes to watch. The internet I do enjoy but when power is off, I find all sorts of things I can do and is good for me not be sitting there on the net. I really watch my time on the net, in morning if I have time and evenings a few hours if not the best of weather to be outside. There are days on end when I don't have TV on.

 

[Jerry1]

I’m way more active in the warm weather but in the winter, there’s a few shows I like to watch in the evening and I definitely spend more time on the internet throughout the day. Thankfully, my internet connection through my phone is working well enough to check in here and do some surfing. It just won’t handle any video streaming right now. I’m pretty sure that’s just because of the added traffic with so many people with power/internet out.

 

[CaptTom]

I have to side with Jerry on this one. When the power and internet are out, and the weather outside is unpleasant, camping out in your own house can get old quick. You can only read so many books.

On the other hand, staying warm and having all the light switches work because you were prepared feels good. Shutting everything down once or twice a day for generator checks is sort of rewarding and reassuring.

I had our primary generator fail during the last 26-hour outage. At 2 AM, of course. In the pouring rain and gale-force winds. Bad capacitor, no way to fix it without parts. The secondary backup wasn't running well, and I was a nervous wreck wondering when that one would fail. Had a plan for a tertiary backup to at least run the boiler and sump pumps, but that would have been a massive hassle.

 

[nhcycling]

Read the manufacturer instructions carefully. We used to have a Generac generator that we pulled out of the garage, during one particular nasty ice storm years ago we ran it continuously for 4-5 days. We just added gas every so often. There were no issues. We sold that and now have a stand by whole house with a propane tank that kicks on if there is a loss of power.

 

[ERD50]

I read on-line that a Generac generator is rated for ~ 3000 hour life. That's fine for the occasional black-out, but I knew someone who was considering one for an area where they could expect a couple week-long outages a year (and running a business, they need 24/7 power). But even at that, you might get 10 years out of it.

For use beyond that, it's time to consider an industrial grade unit. He looked into them, but they were like 5x the price. Better to replace it a couple times.

While I would want to limit the use as much as I can, that's what you got it for, and 3000 hours seems to give you a lot of buffer. Go for it I guess.

-ERD50

 

[Jerry1]

I’m not too worried about the 3000 hours. My generator is literally a small 4 cylinder car engine. If needed, it could be rebuilt. Also, I’m thankful that I could replace it if needed. I’ll do what I can to maintain it properly but at some point, you just have to say, that’s what it’s there for. My biggest concern is it crapping out when I need it. Not so much the repair.

I had an outage about a year ago and it ran for about 36 hours and then just stopped. Got a guy out to diagnose the problem and he traced it to the starter. Apparently with the starter shorted out, it would not run. Took a couple days to get a starter but by then, I had power back. That’s why, even though I have a whole house generator, I also have a small inverter generator. It will run a furnace and keep the food from spoiling if needed.

 

[Car-Guy]

Read the manufacturer instructions carefully. We used to have a Generac generator that we pulled out of the garage, during one particular nasty ice storm years ago we ran it continuously for 4-5 days. We just added gas every so often. There were no issues.

My primary generator is probably >15 years old now and I have no idea how many hours it's run over those years... (but a lot) Still I would not think twice about running it for several days straight, if needed. I'd check the oil at the first startup and then maybe in a couple of days, during fill ups. It just doesn't burn much (if any) oil... I do have a backup that I only crank up once or twice a year, just to run it. I do change the oil in them once a year and add sta-bil to the gas. Zero issues.

 

[Jerry1]

Update

Well, glad I got good advice. Shut down and checked the oil today after about 24 hours. Added about 3/4 of a quart. Yesterday when I checked, it was at about 3/4 in the operating range. Today it was right at the low point of the range. Topping it off took about 3/4 of a quart so it’s using about 1/2 quart or so in 24 hours. Good to know.

Went out and got a couple quarts of oil. Lot of places closed with no power. Couldn’t get the exact same oil that’s in it right now, but found one that’s close enough. I’ll change it all once this is over. Hopefully soon, but they’re saying probably Sunday (two more days).

 

[skyking1]

glad that went as planned. That is one backup that has earned it's keep in one go!

 

[1242Vintage]

Having a snowy and windy week on the west coast. Power is currently out and standby generator plugged in and purring next to the panel to keep us comfy and entertained.

Manual says it can go 48 hrs without shutting down to check oil level, so that’s what I do.

Kind of nice during long outages to have lights, internet, and a cold fridge and freezer full of cold food.