Portable Generators - 15W40 in freezing weather?

[SupremePossum]

With how cheap you can pick up good 0&5w synthetic oils these days, the only justification IMO for a 15w oil is if 1: it’s completely free, and 2: it’s going in something like a 1940s Farmall.

If this is the case, then you can't win around here! Everyone is an expert and tells you one thing, then tells you the exact opposite. For better or worse, I'm running 15W-40 for a while, because I have a lot of it now

Just doing some head math, if you leave the 50w heat pad plugged in 24/7, and your electric is just $0.10/kWh, you’re talking ~$4/mo

Zero reason to leave it plugged in all the time, so no problem there

Think about it- the very best ICEs are about 38% efficient, and generator engines are probably in the 25-30% range, meaning for every 5HP of output the engine is wasting about 12HP of heat, or ~9kW for about 3.7kW of output. 50W is likely going to be inconsequential especially if there is any moving air near the cylinder block.

I don't think you can use those stats on a block heater. I for sure will do some tests, I do have a FLIR

Now it needs to get cold...

 

[Sumboodie]

Block heaters are $15 for 2...

And powering with what?

$15 for 2 vs like $5 of oil....

 

[SupremePossum]

And powering with what?

$15 for 2 vs like $5 of oil....

Right but the $15 heater works forever (Or until it dies), plus, no mess

That $5 of oil is just $5 down the drain.

Powered via a power outlet in my garage, or wherever else you want to plug it in.

 

[jkingrph]

IIFC Briggs recommended syn 5/30 for all temperatures, that's what I use in my B&S 5,000 watt unit, I ran it on this oil at least 10 hrs a day for 2 weeks during Superstorm Sandy with basically no oil consumption.
PS (second pic)
make up something like this for a no-mess generator oil change....
View attachment 252403View attachment 252404

I have a large Honda 11Kw generator. I installed a Fumoto drain valve and an extension hose to drain oil. The way it is made if you do not do something and use the factory drain plug then you have oil all over the frame. It's now 19 years old and having always kept it covered looks as clean a new.

 

[oil pan 4]

Its getting colder, and I live in Texas. Assuming we have some kind of mega winter freeze like 2021 and I loan out my portable generators, is the Kirkland 15W-40 I have in them fine, or should I swap the oil for 5W-30?

If 15W-40 is not fine, would it be fine if I kept the engines warm before starting?

Your oil viscosity limit on a pull start is going to be around 1,000 to 2,000 cP. On a 15w oil at freezing book value is 1,300 cP. So by +20f you won't be able to pull start it and you only might be able to pull start it a freezing depending on how thicc you are.
Normally I say run a 40 or 50 weight oil in generators, but if you're running it below freezing, the oil in the engine will be about 50f cooler than summer time temps. A 0w-30 or 5w-30 will be fine. Just remember to change it if you're going to run it for extended time in the summer.
For the electric start a 15w should work but isn't ideal for cold starts in a splash only oiling system.

 

[SupremePossum]

Well the 50w block heater arrived, and actually pulls 80w which was somewhat expected based on reviews of the 150w unit

Wow, it gets HOT fast. Now to figure the best way to attach to to the engine, and where

 

[locomaster1969]

Mobil1 0w30 will work great in your genny. Easy to pull start in freezing weather, so easy that my 10 year old son can pull start the genny at temps well below freezing here in Kansas. Genny is kept in an unheated shed. Dino oil in a pull start genny at below freezing temps is tough to start even for me. I have been there and done that. Try the 0w30 and no more worries.

 

[Plumb Bob]

That $5 of oil is just $5 down the drain.

I agree. Keep it in and return the heaters. No need in Houston.

 

[SupremePossum]

Heaters are going on the generators as we speak

Dumping brand new oil is so dumb.

 

[oil pan 4]

Heaters are going on the generators as we speak

Dumping brand new oil is so dumb.

Get yourself a oil line that goes in place of the drain plug. It makes oil changes a breeze. It will make collecting oil for reuse easy. Altho if say you're running 20w-50 and you wait till Winter to swap it out it will need to be drained hot or it will come out of there like honey on a cold day.

 

[SupremePossum]

Alright well, the 50w stick on block heater works better than expected. Its not super cold out, but I think this is still a good test. When it gets cold, I will test again for sure. Outside temp was right around 52 the entire time per my weather station.

Some notes

* Stick well, may use some high temp glue/epoxy if I'm happy with the install just to make sure
* It cycles on and off, so it seems the thermal transfer is not super great. Of course the front of the pad gets hot too, so a bit of wasted heat. I think anything more than 50w would be overkill for this size engine.
* Do I trust it powered on in my garage? Unsure. I may put in a small 2a inline fuse


On my cheap WEN GN400iM which is pull start, there is a nice smooth area right near the dipstick, and it just happens to be a perfect size. I cleaned the area with soap and water, and then some alcohol, and slapped it on there, and it seemed to stick really really well.

Starting temp, 54.8. This generator lives in my garage, so I was surprised to see how close to ambient it was. I thought it would be warmer! It did get much lower at night, so possibly its still recovering. Note that after reading temp, I put the dipstick back in

Plugged into my Ecoflow River 2 Pro

As you can see, it draws more than 50w, its actually 77w

After 10 mins, the oil is reading 70.8 degrees. The dip stick was now warm to the touch, and the entire side and the bottom of the generator was warm.

Of course the reading is right near the heat pad, however I did move the engine around a bit and even pull the cord a little just to try and move the oil in the pan, and it stayed the same. This is a very small engine, so I think the oil is probably a fairly even temp. You can see its quite narrow

After another 10 mins, so 20 min total, its at 82!

Did some cable management

And fired it up (Started first pull) and charged the Ecoflow back up

I let the generator run for around 30 mins and it seemed to stay stuck on just fine

 

[SupremePossum]

Tested it a few times just to make sure it wasn't going to burst into flames or stop working, so I got some high temp RTV and stuck it on there good

A mosquito kept trying to get me while I was doing it, thats my excuse for the non perfect application!

 

[z71bill]

If it gets to the point you need it and you can't start it - drain the 15W40 and put in 5W30.

 

[dlundblad]

15w40 is fine in freezing temps.

 

[eljefino]

You could probably put half a dozen tea light candles on a plate and leave them underneath the frame for half an hour and get a similar if not better result.

 

[SupremePossum]

You could probably put half a dozen tea light candles on a plate and leave them underneath the frame for half an hour and get a similar if not better result.

If a burnt down garage is the goal, I suppose?

 

[SwampSurvivor]

I put Rotella T6 in my Predator generator for winter. It does have electric start (on a battery tender) but some winters it can get cold .

Hopefully that's "thin" enough.

 

[z71bill]

I put Rotella T6 in my Predator generator for winter. It does have electric start (on a battery tender) but some winters it can get cold .

Hopefully that's "thin" enough.

T6 comes in many different grades.

5W30, 5W40, 15W40 and 0W40 that I know of - could be others.

 

[SwampSurvivor]

T6 comes in many different grades.

5W30, 5W40, 15W40 and 0W40 that I know of - could be others.

It's the original brotella 5w-40.
I forgot it came in all sorts of grades. I bought it for $1 a quart years ago on clearance. 2017?

 

[Silverado12]

I think 15W-40 should work. FWIW I use NAPA brand 10W-30 full syn in my generator and sometimes in my Briggs 17.5 riding mower.