Occasional users: how often do you change oil?

[Motorboatin]

The problem with oil analysis is the cost. Blackstone charges $28 and it can be cheaper to just change the oil

 

[Herkypilot]

Well that is the answer for the OP. With oil analysis, he may discover there’s nothing wrong with going 3+ years on a low hour machine. My manual doesn’t even mention any change based on anything other then hours used so if an owner is going to change based on something else he is in uncharted territory without an analysis.

Regardless it’s your money, do what you want.

 

[Turbys_1700]

Yearly is the easy answer. You know it's done. I doubt very seriously that the oil is not up to specs with low hour usage. I think my T4.75 states 600 hour oil change intervals. I don't farm so 600 hours per year is not going to happen. I had it serviced at my dealership when I purchased it with 1K hours on it. I will do it myself at yearly intervals just to "feel good".

 

[Ortimber]

I change engine oil either by hours as recommended by the manufacturer or annually, whichever comes first.

It is my belief however that we all change oil more than we need to. Including me. Lab testing would probably save us all $ in the long run.

 

[ccsial]

I do about 70 hours/year. I change in the spring. I use synthetic Delvac one.

 

[CobyRupert]

What's up with yearly being a magic number? What makes oil "old" and needing change?

I'd have no problem changing my oil and refilling from a new jug that sat in my garage for a year or more, so what's the difference if it sits in the engine for a year? Metal container versus plastic?

Experts may chime in, but it seems old needs changing when it gets contaminated by a couple things: Little metal pieces that enter it from normal engine wear. This amount is mostly a function of engine revolution counts, as we measure/estimate by running hours/miles etc..).

Other thing that ages oil are contaminants that enter from fuel (blow-by, etc...) Again, this amount is mostly a function of engine revolution count. And perhaps operating temperature (for a particular engine). The amount that stays in the oil is probably a function of how long engine is operated at operating temps (versus short trips).

I'd argue that if your not putting enough hours so that oil gets changed once a year based on hours, then the real question is: Are these short hours because engine is only started and run for a short period of time? If so, then maybe yearly change is good. If engine regularly gets warm, I'd go by hours (or miles, etc..)

With synthetic oils, I let some low hour engines go 2-3 years between changes, others that have single digit/teen hours per year (wood splitters, garden tillers, push mowers, etc.. ) I let go 5-6 years and don't worry about it.
:2cents:

 

[EddieWalker]

My reasoning for changing my oil in the spring is because it sits outside all winter long, and there is a strong possibility that after sitting for months, moisture has built up inside the engine block. I believe that it's smart to go into the spring and summer with fresh grease, filters and oil. I never change my hydraulic oil, I just top it off when low, which is usually a result of blowing a hose.

 

[Gary Fowler]

My reasoning for changing my oil in the spring is because it sits outside all winter long, and there is a strong possibility that after sitting for months, moisture has built up inside the engine block. I believe that it's smart to go into the spring and summer with fresh grease, filters and oil. I never change my hydraulic oil, I just top it off when low, which is usually a result of blowing a hose.

I think you nailed it with storage issue. If engine is stored inside an enclosed structure, I dont have an issue with going more than a year when you have low hours and use a full synthetic oil. Outside storage where sun heats up and nights cool down could cause lots of moisture to accumulate in the crankcase. The other issue is short runs- do you run the engine long enough to boil off any moisture in the oil?

I change oil in my cars when the computer says 10% life left and dont even think about the age of the oil. All my vehicles go straight into a garage when I stop. My tractors are the same way so I change per hours of use. I write the date and hours on the filter when I change the oil. The other issue I watch for is low oil on the dipstick. If engine uses a bit of oil and it is low on oil, engine hours are short, I may still change it. If the engine holds two quarts and it is a quart low, it makes no sense to pour in half the amount of oil needed to change it. So far none of my tractors/cars/trucks/motorcycles or boat use any oil between changes. I do have to keep an eye on the small lawnmower engines for oil consumption but I change them yearly regardless of the hours.

Another issue to consider with small engines is if the engine has an oil filter. Ones with an oil filter can go longer than small engines that dont have a filter.

 

[CobyRupert]

My reasoning for changing my oil in the spring is because it sits outside all winter long, and there is a strong possibility that after sitting for months, moisture has built up inside the engine block. I believe that it's smart to go into the spring and summer with fresh grease, filters and oil. I never change my hydraulic oil, I just top it off when low, which is usually a result of blowing a hose.

As I understand (rightly or wrongly), most moisture and un-burnt fuel in the engine block gets evaporated and vented (or goes to intake) when engine comes up to operating temperature.

But you raise a good question about hydraulic oil (systems): Are they vented? How warm/hot would they typically get if you're just raising a bucket up and down occasionally or steering (and not running pto, and tractor isn't a hydro, etc..)? Warm enough to evaporate condensation?

 

[EddieWalker]

I understand that as an engine warms up, moisture in the crankcase evaporates. What I worry about is that over the course of several months of not running my tractors, that the amount of moisture that gets into the crank case will affect the ability of the oil to lubricate everything until it evaporates. How long is too long to run it, and how much moisture is too much? Since I have to no way of measuring this, I just change the oil. Since I'm changing the oil, I also replace the filters and grease everything.