Viscosity and hours between oil changes in small air cooled engines.

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My B&S 2200 Genset is supposed to have an oil change every 50 hours. However, during the last terrible hurricane I had to rely on it for 14 hours a day for 3 weeks which = ~ 300 hours. The oil came out dark but, not black. I changed oil at ~ 300 Hr. and ran to flush out the remaining fuel. Again I changed the oil after ~ 4 hours and it looked clean. You think I was concerned about the 50-hour recommendation oil change-NO
 

z71bill

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My B&S 2200 Genset is supposed to have an oil change every 50 hours. However, during the last terrible hurricane I had to rely on it for 14 hours a day for 3 weeks which = ~ 300 hours. The oil came out dark but, not black. I changed oil at ~ 300 Hr. and ran to flush out the remaining fuel. Again I changed the oil after ~ 4 hours and it looked clean. You think I was concerned about the 50-hour recommendation oil change-NO

Well they say ignorance is bliss.

If you used some high end oil maybe you will be OK - Amsoil or whatever - or if you were running 15W50.


Did you just not have the foresight to have some oil on hand before a major storm - or was running it 300 hours your plan?

I am not saying you can't run way over the recommended OCI - but why would anyone want to?

When it starts smoking and using oil you will at least know why.
 
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Jan 29, 2022
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B&S states that the optimum oil is 5w30 full synthetic and that is what I use in my John Deere 20 HP B&S twin and 2200-watt B&S converter gen set. It' fun to try to outguess the manufactures but, in reality they have the long-term data, and we don't. JMO. Ed

Read it again. Optimum engine oil for a Briggs generator is synthetic 15W50.

15W50 Vanguard oil- Varying temperature range. For continuous-use, such as commercial lawn cutting or pressure washing.

A generator is certainly “continuous use.” A air cooled Briggs/Generac generator used in Texas or Florida should use 15W50, per the manual.

I owned a small engine shop in Florida and I read the engine manuals from every manufacturer every year . Going back to 2000 or so.

For years it was just “Use SAE 30 or 10W30”. Then something happened. Briggs and Kawasaki and Kohler and others began blowing up engines on commercial mowers in Florida. 30 weight is NOT sufficient for a commercial mower in Florida. And then… the engine manuals changed. They added 40 and 50 weight oils, when before they just recommended 30 weights. This is what we call a clue. They got tired of warranty repairs on blown up engines.

As someone that has done thousands of oil changes in south Florida on generators , mowers, and small engines, you see patterns. What works, what doesn’t. You see guys using 30 weight oil (their request) with low hours on their engines and the engines are starting to prematurely smoke.

If you live in arctic conditions , or have an oil cooler , or water cooled, then 30 weight is acceptable.

In Houston or Florida in a generator? You really can’t go wrong with a 40 weight to START.

If I owned a Honda 2800 watt generator in Houston , it would get SAE40, 15W40, 5W40, etc. changed every 50 hours.
 

z71bill

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Read it again. Optimum engine oil for a Briggs generator is synthetic 15W50.

15W50 Vanguard oil- Varying temperature range. For continuous-use, such as commercial lawn cutting or pressure washing.

A generator is certainly “continuous use.” A air cooled Briggs/Generac generator used in Texas or Florida should use 15W50, per the manual.

I owned a small engine shop in Florida and I read the engine manuals from every manufacturer every year . Going back to 2000 or so.

For years it was just “Use SAE 30 or 10W30”. Then something happened. Briggs and Kawasaki and Kohler and others began blowing up engines on commercial mowers in Florida. 30 weight is NOT sufficient for a commercial mower in Florida. And then… the engine manuals changed. They added 40 and 50 weight oils, when before they just recommended 30 weights. This is what we call a clue. They got tired of warranty repairs on blown up engines.

As someone that has done thousands of oil changes in south Florida on generators , mowers, and small engines, you see patterns. What works, what doesn’t. You see guys using 30 weight oil (their request) with low hours on their engines and the engines are starting to prematurely smoke.

If you live in arctic conditions , or have an oil cooler , or water cooled, then 30 weight is acceptable.

In Houston or Florida in a generator? You really can’t go wrong with a 40 weight to START.

If I owned a Honda 2800 watt generator in Houston , it would get SAE40, 15W40, 5W40, etc. changed every 50 hou
double post?
 
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z71bill

Thread starter
Joined
Sep 26, 2021
Messages
83
Read it again. Optimum engine oil for a Briggs generator is synthetic 15W50.

15W50 Vanguard oil- Varying temperature range. For continuous-use, such as commercial lawn cutting or pressure washing.

A generator is certainly “continuous use.” A air cooled Briggs/Generac generator used in Texas or Florida should use 15W50, per the manual.

I owned a small engine shop in Florida and I read the engine manuals from every manufacturer every year . Going back to 2000 or so.

For years it was just “Use SAE 30 or 10W30”. Then something happened. Briggs and Kawasaki and Kohler and others began blowing up engines on commercial mowers in Florida. 30 weight is NOT sufficient for a commercial mower in Florida. And then… the engine manuals changed. They added 40 and 50 weight oils, when before they just recommended 30 weights. This is what we call a clue. They got tired of warranty repairs on blown up engines.

As someone that has done thousands of oil changes in south Florida on generators , mowers, and small engines, you see patterns. What works, what doesn’t. You see guys using 30 weight oil (their request) with low hours on their engines and the engines are starting to prematurely smoke.

If you live in arctic conditions , or have an oil cooler , or water cooled, then 30 weight is acceptable.

In Houston or Florida in a generator? You really can’t go wrong with a 40 weight to START.

If I owned a Honda 2800 watt generator in Houston , it would get SAE40, 15W40, 5W40, etc. changed every 50 hours.

I have a few 15w40 and 5w40 oils in my stash - I will use them if the outside temp is really hot -

During the Texas deep freeze I was using 5w30 Mobil1 -

The owners manual of my EG2800i says change the oil every 25 hours - if running it hard. It takes ~16 ounces of oil so I see no reason to try and stretch it -

The reason for the thread was to explore "light" VS "heavy" with the base case being very frequent oil changes.

From my reading heavy oils don't automatically lubricate better than lighter oils - too heavy causes more friction - which creates more heat - too light breaks down faster losing its ability to lube and gets you catastrophic engine failure!

So if in doubt a little heavier may be better - but I don't see a 5w30 full synthetic breaking down in 24 hours -

Heck if I am running in 100+ degrees I will be using 15w40 and changing it every 24!

So what kills the generator engine faster -

Using something with a 30 instead of a 40 or not changing it on schedule?
 

4WD

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Running Redline 10W30 in my WGen9500 - note the HTHS and Noack - this is PAO/ester synthetic


10W30 is the OEM spec’d oil
 
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Aug 16, 2022
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down south
My B&S 2200 Genset is supposed to have an oil change every 50 hours. However, during the last terrible hurricane I had to rely on it for 14 hours a day for 3 weeks which = ~ 300 hours. The oil came out dark but, not black. I changed oil at ~ 300 Hr. and ran to flush out the remaining fuel. Again I changed the oil after ~ 4 hours and it looked clean. You think I was concerned about the 50-hour recommendation oil change-NO
i went through a 2 week power outage after Fiona and i was certainly concerned about my Honda generators. these things aren't cheap and as a bitoger i obsess about oil. since my gennies don't have an oil filter i will never push my oci over 100 hours. i was ocd during the two week run and changing 50hrs. did you not have any oil stashed away? will you keep the 300 hour oci?
 
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I'm not that concerned with the high temp oil where I live. I'm running 10W30 In my Predator 6.5K because it is a pull start. I keep 20W50 on hand with the thought that I could switch it during a re-fuel.
 
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Nov 1, 2015
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Long Island NY
I ran my B&S Genset on Mobil 1 5/30 for about 10 hrs a day for 2 weeks during Sandy here in the northeast that’s approx 140 hrs I changed the oil when the power came back on and it’s been fine all these years. I change it every 2-3 seasons if not used for an outage. If used for an outage I change it when it’s over & power is back on. I run it once a month so the gas in the carb doesn’t go bad. So far so good I have not had to clean out the carb yet…

BTW some of those generator cords that you can buy from Amazon have cheap plugs & receptacles that don’t make good contact. I had to return a few & wound up making my own cords with good quality 4 conductor cord & Leviton plugs & receptacles. Always good to have a spare one on hand. I also had to replace the 240v receptacle in the gen set for the same reason; Briggs used a cheap plastic one that loosened up & one leg was getting intermittent or no output. Did the same thing replaced it with a Leviton. No more problems…..
 
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z71bill

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Sep 26, 2021
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I ran my B&S Genset on Mobil 1 5/30 for about 10 hrs a day for 2 weeks during Sandy here in the northeast that’s approx 140 hrs I changed the oil when the power came back on and it’s been fine all these years. I change it every 2-3 seasons if not used for an outage. If used for an outage I change it when it’s over & power is back on. I run it once a month so the gas in the carb doesn’t go bad. So far so good I have not had to clean out the carb yet…

BTW some of those generator cords that you can buy from Amazon have cheap plugs & receptacles that don’t make good contact. I had to return a few & wound up making my own cords with good quality 4 conductor cord & Leviton plugs & receptacles. Always good to have a spare one on hand. I also had to replace the 240v receptacle in the gen set for the same reason; Briggs used a cheap plastic one that loosened up & one leg was getting intermittent or no output. Did the same thing replaced it with a Leviton. No more problems…..

What does your owners manual recommend for hours between oil changes for extended / heavy use?

Some recommend 100 hours but then have an * and it will say 25 hours when used continuously or heavy use.

I could never go two weeks without changing the oil in my generator - I bet I was more like every 20 hours during the Texas freeze - mine only uses 12 ounces of oil - it just seems like such a small cost I will never understand why so many think it is a good idea to run so many hours.
 
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