Oil & Fuel Add 20 year old oil to motor?

[CobyRupert]

Made the trip to mom’s house to mow her lawn with her little Honda Harmony riding mower. Forgot to bring a quart of motor oil to top off the dipstick.

The oil level was “just” below the mark on the stick. That motor only takes ~1.5qt of oil, so there’s not much to loose (if a leak suddenly got worse), and I’m occasionally mowing on some hills.

There was a case of unopened Castro 10w-30 oil in her garage. My late dad bought it 20+ years ago. I shook a bottle up, opened it, and it looked like…oil.

To use or not? I added about about 1/2 to 3/4 cup.

Was it better than nothing? Or worse than (adding) nothing?

 

[LS Tractor Owner]

I don't think there would be any issues at all. I'm not a specialist chemical engineer, but if it was sealed.... it's good.

 

[ROUSTABOUT]

I don't think there would be any issues at all. I'm not a specialist chemical engineer, but if it was sealed.... it's good.

I never worried about old stuff until I got old. Then I realized I was too old to worry about it.

 

[ruffdog]

Agree with the above posts....use it.

 

[ruffdog]

The only problem would be if a person uses old oil in a modern auto. Some of the heavy metals may raise havoc with the emissions.

 

[gstrom99]

Yes. Use it w/o worry.

 

[Captain Dirty]

For further reassurance: On the Castrol bottle will be a printed, "API donut". The center contains the viscosity, and the top part of the donut shows the API service rating "API Service S_" where the blank is likely to be an "H" (the latest and highest rating from 1993 to 1996), a "J" ('96 to 2001), or an "L" ('01 to '04). (Current ratings are SN, SP.) The ratings are said to be backward compatible.
The Honda Harmony was a machine of the '90s. If your late father kept the owner's manual, it would likely specify the rating SH or SJ. Even if you cannot find the manual, do not lose sleep over using 20 YO oil in a 30 YO motor.

 

[Have tractor did travel]

Using old oil was better than nothing. However, I take a divergent view than the others.
Oil additives begin to lose their effectiveness in five years. OK to use in a low value motor, especially mixed with a greater quantity of new oil. But do not use by itself, and I'd not use it in an expensive motor. Good that you shook the container - any additives that separated, were remixed, and fully poured from the container.

 

[ruffdog]

Good that you shook the container - any additives that separated, were remixed, and fully poured from the container.

 

[TractorTYMe]

It's a riding mower, not a Lamborghini. Open a bottle of oil and top it off

 

[RalphVa]

Agree with LS tractor owner. Also a chemical engineer who worked in lube oil industry for 31 years.

 

[stevem5215]

I had a sample sent in for analysis from a drum of oil I purchased at an auction. It was labeled Pennzoil Multi duty. Turned out to be just old standard machine 30w oil. I used it for years in my Ford 1900 Diesel without any issues. Sold the tractor and still have some of that oil in the drum. I would only use it on equipment that could use that 30w and in my case it's a couple of small engines I still have laying around. I will eventually use it all up but probably will be 90 by then. The analysis of the oil came back that it was fine as the drum was sealed for years and all of my years too. Oil won't go bad but like mentioned this one has no additives in it basically. Simple machine oil.

 

[dodge man]

They have made a lot of improvements in oil since that was made, it’s probably gotten hot and cold several time, and I’d still go ahead and use it in a small engine and not worry.

 

[California]

... I’d still go ahead and use it in a small engine and not worry.

Yeah.

Listen to Ralph above (Post #11). If 20 years ago spec 10-30 oil could cause damage in a simple application - in 30 years as a lube oil engineer, Ralph would have heard about it.

Not a problem.

 

[jigs_n_fixtures]

Using old oil was better than nothing. However, I take a divergent view than the others.
Oil additives begin to lose their effectiveness in five years. OK to use in a low value motor, especially mixed with a greater quantity of new oil. But do not use by itself, and I'd not use it in an expensive motor. Good that you shook the container - any additives that separated, were remixed, and fully poured from the container.

I’m under the impression that the oil breakdown occurs due to heat, and absorption of moisture from the air. That a sealed can of oil, should last almost indefinitely.

If I’m wrong educated me.

 

[ultrarunner]

I was using metal cans of oil for the outboard from the 1950's

Had one of my old car friends with me one time and he said what are you doing???

I sure got a scolding but not for what you thought.

He said he could sell all I had at $25 a quart full or $10 a can empty to collectors... this is 10 years ago...

 

[scaredychicken]

Oil, is better than No Oil

shouldn't be a problem, still a fresh can

 

[California]

Has anyone here seen harm from bad oil? (Assuming a recognized brand, not contaminated, or incompatible with modern emissions).

 

[TimberFarm]

I was using metal cans of oil for the outboard from the 1950's

Had one of my old car friends with me one time and he said what are you doing???

I sure got a scolding but not for what you thought.

He said he could sell all I had at $25 a quart full or $10 a can empty to collectors... this is 10 years ago...

That's good to hear.
I have two quarts of Castrol GTX in the old qt cardboard sided cans with metal top and bottom that were in a box I bought at an auction 20 years ago.
I have saved them all these years thinking exactly what your friend's thinking.

 

[JCoastie]

70yr old oil test, pretty entertaining.