UOA - Recycled oil ran between 2 cars ~Experiment~

[bxd20]

Since nobody else has said anything, I'll bite.

When you drain the oil from the Civic, you are putting it into the Accord. You are doing this because you believe that there is some "life" left in the oil (however YOU define life, which doesn't matter to my point).

My question to you is, why don't you just use up the rest of the life of the oil in the Civic, then dump it?

Here at BITOG it is understood that oil does not degrade linearly. You get "x" miles of great protection, and then things go downhill fast. That is why changing your oil every 500 miles doesn't lead to less wear than changing your oil every 1,000 miles. That's why those who want to extend their OCI watch for trends and try to find that spot where wear accelerates.

So the only way I could see your experiment extending the usefulness of your oil overall, is, if you could demonstrate that the oil has reached "0" life in the Civic before you move it to the Accord, and then demonstrate that it is still a capable oil in the Accord.

Or, let me put it to you with an example. The numbers are made up but the point is what matters.

Say you can run your oil 3,000 miles in the Civic followed by 3,000 miles in the Accord.

Between the two cars and two oil changes, yields you 12,000 miles of total motoring.

BUT - because the Civic is 'harder' on oil than the Accord, if you put one oil change in the Civic and ran it to 0% of life, you might find you get 4,000 miles. And if you put fresh oil in the Accord, you would find it ran to 8,000 miles. Thus giving you 12,000 miles overall, once again. Except, by transferring it, you're doing twice the work and taking up twice the time.

So again, for this to be a meaningful experiment, you need to:

FIRST - run the oil to the end of its life in the Civic. The point at which wear begins to accelerate. Establish that mileage with a trend of UOA.

THEN - after the oil is considered useless in the Civic, transfer it to the Accord. Then run UOAs to find if it can protect that engine. If you decide to do so, I would sample every 1,000 miles. I think you will find that once the oil is done in the Civic, it's DONE.

 

[Artem]

You brought up some interesting points there and i'll try to explain everything to the best of my abilities...

First of all, i'm not doing twice the work by dumping used oil into the accord. I drain the oil into a clean pan and then pour it into a fresh oil container (as i would do anyway to later take the oil to a dump site)

When it comes time to change the oil in the Accord, i bump the whole 5q container into the engine and call it a day (no different then dumping fresh oil from the same 5q container)

Now, I'd be more then happy to run the oil longer then 3k in the Si however, i want to maintain the best possible engine protection/cleanliness, hence the short intervals. I don't give a rats behind about the 18 year old Accord with 215k on the clock. The owner is planning to trade it in, in a few years anyways because the rest of the car is falling apart.

I've been changing the oil every 3k in the Si since i got it new. For 4 years i've been throwing away oil which according to the UOA still has plenty of life left in it, showing a TBN of 7.0+ with a quart of top off.

Why throw away such good oil?

After being used in the Accord for another 3k, the UOA showed that there's still enough TBN left for a longer run next time, and since wear rates are still within average spec, i know the oil is still doing its job in the old grocery getter.

I'm reusing the oil into a 2003 Accord as well, running it for an additional 6k after its been used in the Si for 3k... the UOA from that car also shows plenty of TBN for a longer run next time and wear rates are within average as well.

Why would i run the oil down to pretty much 0% oil life AND THEN bump it into another engine???

that sounds like a recipe for disaster.

The whole point is to use up the remaining life in the oil before completely trashing the oil. No point in throwing away oil with a 7.0+ TBN after 3,000 miles.

BTW, i plan to extend the OCIs in the Si right up until wear begins to increase, slightly. I want to see if i can squeeze out another 1-2k outta the oil while not increasing wear but first i'm experimenting with different brands of oil to find an oil robust enough to last 3k worth of abuse in the Si without shearing into a 20 grade. I currently have Redline in the block which will be ready for sampling in roughly 500 miles (about 2 weeks or so)

 

[bxd20]

Originally Posted By: Artem
The whole point is to use up the remaining life in the oil before completely trashing the oil. No point in throwing away oil with a 7.0+ TBN after 3,000 miles.


EXACTLY.

What is the point in draining this oil from the Civic at 3,000 miles when it could clearly be run longer without any additional increase in wear? You're not preventing wear in the Civic. You're not saving money. And you are spending extra time, which may not matter to you.

 

[Artem]

You're still not getting the point... I'm draining the oil out of the Si after 3,000 miles regardless of how much life is left in it. I simply don't feel comfortable pushing the engine to its limits (well technically past its limits, since i'm revving to 8,600 RPM when the factory redline is 8k) Been doing it for years.

The fact that i'm reusing the oil for an additional X amount of miles in the ol' Accord instead of BUYING NEW OIL = ummmm, savings??? $$$

Lets not forget i'm also reusing the Amsoil Oil filter in the Accord as well.

I'm only interested in seeing how much longer the oil can keep going while still provide adequate protection in the Accord's engine which doesn't get spun past 3-4k if that (he tries to get max MPGs and drives slooooooow)

 

[bxd20]

"I'm draining the oil out of the Si after 3,000 miles regardless of how much life is left in it."

Because it makes you "feel comfortable".

Got it.

 

[Michael_P]

Dang! I thought this was going to be a NextGen UOA.

 

[Artem]

Originally Posted By: bxd20
"I'm draining the oil out of the Si after 3,000 miles regardless of how much life is left in it."

Because it makes you "feel comfortable".

Got it.


Exactly.

after 3k as per the UOA, the oil sheers into the 20 grade and i feel that's not a good thing @ 8,600 RPM. I'm trying to make this engine last me a while before having to rebuild.

 

[PZR2874]

I don't see anything wrong with changing the oil at the "preferred 3K" with syn.

Try this on a DI'd engine.... Report back ! )

 

[Artem]

I don't get what a DI engine has to do here...?

 

[PZR2874]

Fuel dilution.

 

[Artem]

Got cha!

 

[A_Harman]

I think you may be too conservative draining the oil at 3k miles, even if you are revving the engine to 8600 rpm. I'd bet if you added up all the time you have the engine above 7000 rpm, it would only be ~4% of the total operating time.

 

[Artem]

Although i agree with what you said, it doesn't apply to me because my driving style is not like your average "normal" Civic Si owner.

The Si is modified and is fully tuned on a dyno to extract Max Power! I drive it like a race car, constantly at WOT (wide open throttle) to pass slower moving vehicles. The engine spends a LOT of time in Vtec (the crossover happens @ 5,800 RPM in stock form) with each and every gear, daily!

Although i'm sure the oil could last longer but i choose to pull the oil out @ 3k because the oil sheers into a 20 grade. Once i find an oil capable of handing the abuse, i'll try running it a bit further. I want to maintain 100% operation efficiency. The car is in Race ready mode at any time of the day, after a warm up.

 

[cmf]

Originally Posted By: Artem
Although i agree with what you said, it doesn't apply to me because my driving style is not like your average "normal" Civic Si owner.

The Si is modified and is fully tuned on a dyno to extract Max Power! I drive it like a race car, constantly at WOT (wide open throttle) to pass slower moving vehicles. The engine spends a LOT of time in Vtec (the crossover happens @ 5,800 RPM in stock form) with each and every gear, daily!

Although i'm sure the oil could last longer but i choose to pull the oil out @ 3k because the oil sheers into a 20 grade. Once i find an oil capable of handing the abuse, i'll try running it a bit further. I want to maintain 100% operation efficiency. The car is in Race ready mode at any time of the day, after a warm up.


This is non-productive but I found it funny you said "WOT to pass slower moving vehicles" and you live in Florida. Most people here are either old or mentally handicapped and drive so slow it's obnoxious. It's refreshing to see someone performance oriented driving an recent Civic and the Si model WITH mods and tuning! There just seem to be countless 90s Civics with axleback mufflers being floored around and.. still going slow because it's a stock 90s Civic. I really hate driving in this state.

Your recycling the oil plan sounds good and kudos to driving a sports compact the way it should be driven, with reckless abandon. The wear in the Si looks great, wouldn't even know it was being driven hard. That Accord definitely needs some TLC though.

 

[Artem]

The Si does have some get up and go. Its making 40HP more then stock at this point and is a blast to drive thanks to the short gear rations on the 6 speed tranny, hence why i'm constantly zooming around in traffic. It gets me from point A to B in a hurry.

 

[cmf]

Oops thought the first one was the Civic instead of both the Accord. I searched your posts and found one of your Civic so my statement still stands about the wear looking great on it

.

 

[Artem]

Since the Civic EX gets driven normally and sees a lot of highway use, its a perfect candidate for extended OCIs. I plan to keep raising my OCIs until i reach a nice number. The less oil changes, the better.