Broke in my pressure washer with this. (first 50 hours) Now I have conventional castrol gtx 10w30 in it, mainly because that's what I had laying around.
Straight 30 or 15W40 for hard use air cooled small engine?
- Thread starter z71bill
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Mobil 1 0W-40 hot or cold, it just works!
What does every one think about doing a franken mix in a pressure washer? I am considering Amsoil 5 w 30 with Mobil Delo 15 w 40 full syn? I am also considering topping off my Generac standby Generator with the 15 w 40 . It has 5w 20 in it from the dealer. I live in SC and it gets pretty hot here. I just don't trust 5w 20 in the 90+degree heat. (Or the 5w 30 either for the pressure washer.) Or am I overthinking?
I wouldn't want 5w20 in a generator in 90 degree heat. Everything else you mentioned would work perfect.
It’s what I use in my generator, and other OPE.
I did. My 4gpm gx390 pressure washer runs at 4,000rpm, runs wide open throttle and hits 260f on fairly mild 80f days.
On a typical 100f day I figure the oil could hit 280f.
I run 20w-50 because the oil gets hot and I don't plan to run it below freezing.
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When I purchased my Generac 2200w generator , I asked the dealer what to use . He handed me a bottle 30w oil .
SAE 30 is probably fine as long as it doesn't get real cold where you are.
Check out this link.
A generator in very cold temps somewhere between -17f and 0f had 10w-40 dino oil in it and felt the the engine was locked up.
Other generator with synthetic 5w-30 the oil was so thicc at -17f that the engine would turn over but refuse to fire due to lack or cranking speed (by hand).
20wt for low load on small inverter generator at or below 0f?
Getting ready for the colder weather next week. Expecting to see around 0f or a few degrees lower than that. I have a 2000w (1700w running) Champion Inverter generator. For my use, it’ll probably average between 200-300 watts continuous. -100w for my fireplace insert fan -100w for fridge...
bobistheoilguy.com
SAE30 oil would be even thicker in cold temperatures.
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We don't get that cold here .
I feel like this is the most widely covering oil for all my applications. I'd have a harder time finding an application it wasn't suitable for than one it was suitable for.
I've been running 15w50 in my Briggs & Stratton mower since it's second oil change in 2005. I let the break-in oil run its course, then switched it to SAE 30, and it seem to have an appetite for it, so I went heavier and now it does fine. Running Castrol 10W30 in the Westinghouse 9500 generator, it'll probably be okay for power outages in the winter, but I'll probably kick it up to a 10W-40 or 15w40 if I have to run it in the summer.
An sae30 oil at freezing is going to be almost as thick as a 5w-xx oil at 0f.
Going off that post it looks like several hundred cSt is too thick to pull start a generator. The oil has to be thinner than that to get a pull start.
At freezing sae30 oil will be 1,000 to 2,000 cSt depending on the chart, definitely too thick to pull start. 36 to 40f seems the few hundred cSt limit for sae30.
That's just incorrect or I have been lucky. I am in Louisiana, so my running schedule is similar to Florida. I run 5w30 synthetic in all my ope. 7 years and 243 hours on John Deere D110, 60 hours on John Deere X350, Honda power pressure washer ran 10 hours in hot sun at one time, Generac 7500 running 2 houses after hurricane or after power failure and tiller working garden. Not one oil related failure due to 5w30 synthetic. I also have several push mowers used. Been running ope with 5w30 for as long as I can remember and other things take out equipment out of service.
I change the oil everyday when running the generator (almost) non stop during a power outage.
I have it nailed down - like a NASCAR pit crew.
I have the oil drain pan, the measured amount of oil I need, the funnel and gas can and some paper towels.
I unplug the power cord - shut the engine off - place drain pan under drain hole - pull the fill plug and oil drain plug.
I usually let the engine cool off a little before I refuel - but refill the gas tank while the last few drops of oil are drained.
Install drain plug, dump the oil in - put on fill plug and start it back up - plug power cord back in and GO GO GO.
I have done it is less than 5 minutes - and for such a small amount of oil - I can't imagine going days between changes.
If the temps are above 80 degrees - like they surely will be in Houston after a hurricane - straight 40 weight would be splashable enough.
15W40 pours and flows great at summer temps.
IMHO ---
I think the problem is running 5W30 synthetic for days straight between changes. You have people that look at the owners manual - and it says every 100 or 200 hours between oil changes. But there is many times an * and down below in the fine print it says -
* Change oil every 25 or 50 hours under severe conditions like in hot temps or under continuous hard use.
After two or three days straight use the 5W30 has broken down and no longer provides adequate protection - and then bad things happen.
You also need to recognize - some people think a 5,000 watt generator can run everything at the same time because the load is only 4,750 watts -
Combine both of these together and it can cause catastrophic failure.
I change the oil everyday and rarely run over 50% load at anytime except maybe starting up something like an AC unit or HVAC blower motor. It takes such minor effort to turn something like the HVAC blower off while I make coffee or run the microwave. I think it not only saves a lot of gas but also wear and tear on my generator.
YMMV
I've been using 5w30 mostly Royal Purple HPS in our Craftsman 17 hp lawn tractor for years now with no issues
Oil is drained before storage and filled up and ready to go in the Spring.
I think the dynamics of running a mower for a couple hours a week cutting the grass - and running a pressure washer or generator for hours straight in hot temps are not really the same.
I have used a mix of stuff in my push mowers - whatever I had on hand -
10w30, 5w30, 10w40, straight 30, 15w40 I doubt it matters.
If you want to play check this out.
Sorry, but couldn't you go 50 to 100 hours on a change, especially if running a quality synthetic?
Probably not without an oil filter.
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