Re-using engine oil
 

I serviced my SC a week ago and obviously filled with new engine oil. I may have to drop the oil again shortly to fix a leaking cam cover. Is it OK to collect this oil and re-use?

I would... while making sure it doesn't get contaminated along the way.

Yes.

In theory yes, but I would never do it.

Can you be 100% sure there is no grit or dirt at all in your oil collection system?

I know 10 or 11 quarts of oil is expensive but I just can't see taking the risk. But that is just me and my engine.

Be a good excuse to have two of those little valve things instead of drain plugs. Then you could control the discharge and put it in 1 or 4 quart clean containers. $50 to $100 worth of oil savings would buy 2 for sure.

I see nothing wrong with your plan, provided you capture the used oil in a very clean container. No big deal. Folks do it all the time.

According to diagrams I've seen, oil from the tank is pulled directly into the engine. It's filtered only on the way back into the tank after making the circuit.

It's very tempting to re-use all that oil, but I can't shake the image of those tiny orifices in the piston squirters. I'd go to some pretty extreme lengths to insure that the oil I was putting back was perfectly clean.

Good luck,
GK

Filtration.........
 

I would suggest using a ladies nylon stocking to filter the used oil. If the oil has only a hundred miles or less and uncontaminated, there is no reason to dispose it. The oil has several thousand miles recommended usage before any change oil. The decision is all yours, there is no right or wrong.

Tony

How about not drain the oil in the first place? When you say cam cover I'm assuming you're talking about a lower valve cover. Lots of folks here have confirmed completing valve adjustment without draining the oil. Lift car only on one side and what oil is in the sump will flow to other side. You may have lose a little oil but not enough to complain about. Just top up once valve cover resealed. -J

coffee filter

I re-use oil all the time (have for 25-30 years) - I catch it in a clean pan and then transfer it to clean bottles using a paint strainer in a funnel - never had a problem.

I sure would - best $1.99 you will ever save - until the engine blows that is :eek:

We reuse ours...in a waste oil shop furnace.

When you use the lady's nylon stockings is she wearing them?

reusing 1 week old engine oil will hardly "blow the engine"

you do want to make sure no grit is introduced and a coffee filter will filter out smaller particles than stockings or paint filters

I have never done it, but I would as long as the container you are using to catch the oil is absolutely clean and that you don't knock any dirt into it in the process of getting the oil out.

This is the correct answer to the OP's question. No need to drain a drop to pull a lower valve cover - just elevate that side!

Ditto. Been there, done that.

Wow! You better not reuse that oil! Your 35 year old car may not make it to 300,000 miles. Maybe only 250,000!!!! OMG!

I've tried using a coffee filter recently when I was out of paint strainers and I couldn't get the oil to go through it (would have taken all night for one quart to pass) - must have been using the wrong filters? :D

I don't see a problem re-installing the same oil that came out of your oil tank. If the drain and storage process is as clean or cleaner than the inside of your current tank, should be fine.

It's not as though one were transfusing human plasma while risking the development of acute immune hemolytic reaction. Relax.

However, if there's little trust in a funnel and a collection of sanitized storage containers, one can always gift the FLAPS half a C-note (or more) for a case of virgin 20-50.

Ditto for gear lube.

Sherwood

Agreed. The lengths I would go to are having the oil refined/recycled and repackaged. In other words, go buy fresh oil and recycle the old.

Coffee filter sounds a good bet.
When I said leaking cam cover I meant timing chain covers.
Does the oil need to be drained to remove these?

Not the complete sump volume. To know exactly, position a large drain pan under one chain box, then remove it's cover. The rear end of the car is probably higher than the front, thus only some of the oil will drain out. I suspect about a quart will drip out.

Sherwood

Thanks Sherwood,
I'll try removing one side without draining oil. Probably jack the back end up and put it on axle stands first so the oil will drain away from the chain boxes.

Reusing oil.......
 

I have done this, but before putting the oil back in the engine, I run it thru a very fine screen filter. When I say very fine, it is border line micro. It is built into a funnel w/cutoff valve and hose that I bought from an auto parts store. I also needed to drain the new oil from my engine to do some bottom work and did not want to lose 9-10 qts of new 20-50 oil. So, I ran it thru the filter, cleaning the filter after each 5 qts. All that I found in the oil were some "crumbs" of the block sealer that had "squished" out when the block was assembled. Ran a magnet over it but nothing was attracted to the magnet and nothing looked anything like aluminum. After cleaning the screen, I used the same funnel/filter combo to put the oil back in the engine. That way it had been double filtered.

Just a thought, but I'm sure it would be quite easy to make a small jig to filter the oil through a car oil filter before returning it to the oil tank. A pressure braker bleeder could be used to store and pump the oil under pressure with an 'in line' car filter downstream of the pump.

That way the oil is pre-filtered to the same standard as the oil circulating system before it enters the oil tank.

Cam covers don't require draining oil IMO. Very little stays in the housings.

I used a paint filter but it took a LONG time IIRC. I see no reason to throw out good oil before its led a useful life. As some have pointed out, the better option may be to avoid draining it in the first place.

We used to reuse our racing oil after two weekends in the tow vehicle. Filter it and use it in something less sensitive if you are concerned about cleanliness; otherwise just pour it back into the oil tank of the 911.

Maybe I'm missing the need for this OCD behavior. Other than debris picked up at your exit point or from compromised storage containers, where is this contamination coming from that one has to replicate or improve upon the filtering system provided by the engine's lube system before pouring it back in the engine?

But if you must, here's one method mentioned in several sites:
http://www.endtimesreport.com/cleaning_engine_oil.html

S

Unless the OP's undercarriage is spotlessly clean (and I know many Pelicans have undersides that fit this description) my concern would be any dirt that falls from around the oil-tank, tins, fender-wells, etc. My car isn't terribly dirty underneath, but it does get driven, and some dirt/dust/dead-bugs fall into the drain pail just about every time I change the oil.

There are some good ideas here to avoid wasting the drained oil, but the "don't drain" solutions seem to be the wisest.

If I had to do it, I'd be tempted to carefully pinch the S-hose, then drain the engine case to avoid the tank draining itself down into the case and out the bottom. I'd replace whatever came out of the case with fresh oil. I'm a little too close to a fresh top-end rebuild to want to risk saving a few quarts of oil that badly. That's just my opinion though.

GK

Another reason to use a Fumoto ball drain valve (Tank only. No worries about frozen drain plugs). Source the version with a hose fitting as shown. With the desired length of hose attached, you can extract as many ounces, pints or quarts with minimal odds of introducing rat droppings, industrial fallout, etc. into a narrow-neck oil receptacle.

http://forums.pelicanparts.com/uploa...1373994624.jpg

This is one of those times that the downside far outweighs the upside. Less than $35 for 3 gallons of DELO at Walmart. I inherited some Great Depression era recycle and re-use habits but these aren't lawn mower engines that take abuse and cost little to revive. Absolutely would not recommend re-using oil in these. Then first time you scrub a bearing from a missed particle is when the $35 for fresh oil will seem cheap. What's the downside of new oil? You're out $35 but you gain piece of mind and a cleaner engine internal. Seems cheap security to me.

The oil is only a week old! It has thousands of miles left on it. If you do a clean job saving it then what is the problem? After it is reinstalled, it will still be in better shape than the oil in most of our cars!

Just an FYI but I'd wager this is SOP in almost every auto service shop in the world.

Go ahead and include coolant, trans fluid etc......

I never have and never will reuse a fluid drained. It is stupid to take any risk. I don't even take that risk with the old Volkswagens I've owned. I can't believe a Porsche owner would be so cheap as to attempt it... unless they have no cash left after paying insurance premiums and engine rebuilds at $12g a pop. I would rather eat ramen for a month first!

We have two threads here:

A) Poster is removing timing chian covers and has concerns about dumped oil. Tippy and others answered that. Raise the rear to high heaven and catch the half pint you may loose if any. Change your tensioner and be done with it.

B) Is it advisable to drain low milage oil and possibly re-use. The answer is yes, provided you can maintain cleanliness. Research the topic on engineering forums. This is an old and ongoing topic for Spaceflight concerning water, refrigeration, lubrication and other systems that we here typically just replenish and throw away.. With proper cleanliness you may re-use lube oil.

This "re use drained oil" subject reminds me of the "change oil at 3K miles debate". For some, it seems to offend their sensibilities to go more than 3K on oil, but I find 3K oil change intervals to be grossly wasteful to the point of arrogance. :p

Ditto that. For me this question is more about whether you can keep the oil clean enough to put back in. I love that Fumoto drain - seems like an ideal way to make for a clean dump - it would allow you to drain directly into jugs for drop-off, or for re-use. Nice!