Cold Oil Change?

[copper]

Well, the car's been sitting for the winter and I want to change the oil before I take her out. Seeing as the oil has been sitting there all winter, I'd like to get it out and start fresh.

Do I have to warm the car up first, or can I drain it cold and just leave the pans under longer, like all night to make sure the stuff comes out? I realize it will not flow as smooth, but it should all be settled down below now anyhow after sitting so long.

Thoughts?

Jim

[MovOvr1]

I was thinking and was going to post the same thing. I have everything ready but a nice warm day to drive it to warm it up. Can you do it cold to get most of the old oil out?

Brian

[LakeCleElum]

I think if your car has been sitting all winter, you have mositure in the crankcase. If you drain it cold, change the oil and then run it, you're gonna have this mixing with the new oil until it burns off. If you just run it in your garage, it may not get warm enough.

I would take it on a good drive of at least 20 minutes and then drain the oil.

[Panzer909]

Exactly. The amount of moisture sitting in the engine is not enough to warrant a problem. Don't be afraid to take the car out for a "spirited" drive for 15-20 mins and then drain it. The hotter the better, IMHO. If you want to drain it cold, you'll have to wait a LONG time..........and still will not get all of it out.




Hey copper - are you an avid FM96 listener?

[bill3667]

I believe you want the oil warmed up to suspend the contaniments (sp?) in the oil. If the oil has sat for an extended period of time those contaniments are now resting on whatever surface they were above and will not flow out with the oil when you drain it, no matter how long you leave the drain plug out. If you drain it cold, you will get better oil in the engine when you're done but it won't get nearly all the "bad stuff" out you would have by draining it warm.

JMHO,
Bill W.

[Grady Clay]

I will vote for two oil changes. The first before you start it. So what if it takes a half day to drain the last few drops. You can speed the process with an electric or propane heater. Most oil is in the sump and at the bottom of the tank anyway – it has had many months to gravitate there. The important issue is that you start off with fresh oil.

The engine has to essentially “break-in” again within the first few hundred miles. At that point an oil change when hot is appropriate. For a while treat the engine as if it were a fresh rebuild. Actually, a fresh rebuild is easier on the machinery than improper storage and initial driving.

Here are some good links to study:
“Winter Storage Checklist”
Winter storage checklist?
“Rust vs. Humidity vs. Storage”
Rust vs humidity vs storage
“What do you do about winterization?”
What do you do for winterization?


I would like to hear from anyone who has any issue putting their 911 back in service after winter storage.

Best,
Grady
gradyclay@hotmail.com

[copper]

Grady, that was the thought behind my question exactly...

I have synthetic in the case now. Because of the propensity for leaks, I want to revert back to dino. I have changed the upper gaskets, such as the crankcase breather cover, the thermostat o-ring and the pressure sender crush washer.

Thought if I drained it now, I could change out the drain plug washers and the sump plate and strainer gaskets and then start fresh on these with dino. Then I planned to drive it a little with this and drain it again as I'll be dropping the engine within a few weeks to do the clutch and valves.

So, it looks like I'll drain it out and let it drain for a day and put new dino in, then start fresh with this. Unless anybody seriously objects...

Jim

[randywebb]

It won't hurt to do that. It's just a question of whether the time and effort make it worthwhile. Not for me. But go ahead, esp. if there is a fairly long period where you want to drive the car but don't want to change the oil hot for some reason. You can just change it again - say - half way to to when you would otherwise.

[LakeCleElum]

Grady - I had a winter storage issue once.....Come spring, the clutch was stuck (rusted) to the pressure plate and/or flywheel....I had to push it out of the garage, start it in gear and driive up the road with the clutch in....I broke free in about a block....I was worried I could have torn a chunk of disc material loose as I had a "chatter" for awhile after that....Now, I drive the car at least once per month, as we don't have salt on the roads where I live.....Cheers

[M.D. Holloway]

Always drain the oil hot - you can do a quick test to see if it is really bad off. Take a few drops from the dip stick and drip it on the back side of a business card. Wait about 5 minutes. If you see something that looks like a bullseye, the dark center is carbon and is the beginnings of sludge. If the oil smells the least bit acrid it is time to change it. The fact the oil sat for a few months idle is not really a reason to change it.

[fastpat]

I would agree, changing it as hot as you can stand is prefferable.

Pat

[copper]

Originally posted by fastpat
I would agree, changing it as hot as you can stand is prefferable.

'Prefferable' being the operative word.

I ran the car on a fresh oil change last summer, after 10 years of storage. Was hoping to get the engine dropped before winter, and do the oil change then, but it didn't work out that way. So I have a season's worth of oil, and any crud loosened with it from sitting for years, and I'd rather not recirculate it if I have the option. The car will still be sitting for several weeks while I finish doing some detailing and the topside work, before I get it into the garage for the drop, the clutch and valves.

So, although hot is prefferable, in this circumstance is there any reason not too do it cold as a precaution against the crap that's in there? The oil is fairly dirty, plus it's synthetic and I'd like to start the new upper seals with fresh dino oil instead of heating it up with synth again and letting it find a small route out.

Jim

[randywebb]

No. Do it.

[copper]

Can't get a more straight forward answer than that. Thanks Randy.

Jim

[fastpat]

Originally posted by copper
'Prefferable' being the operative word.

I ran the car on a fresh oil change last summer, after 10 years of storage. Was hoping to get the engine dropped before winter, and do the oil change then, but it didn't work out that way. So I have a season's worth of oil, and any crud loosened with it from sitting for years, and I'd rather not recirculate it if I have the option. The car will still be sitting for several weeks while I finish doing some detailing and the topside work, before I get it into the garage for the drop, the clutch and valves.

So, although hot is prefferable, in this circumstance is there any reason not too do it cold as a precaution against the crap that's in there? The oil is fairly dirty, plus it's synthetic and I'd like to start the new upper seals with fresh dino oil instead of heating it up with synth again and letting it find a small route out.

Jim

I see, it wasn't put away with clean oil, that's a whole different deal.

I'd recommend you change the oil before starting it, run it until it's hot and then change it again. Costly at first blush, but really cheap in reducing the risk factor down the road.

I'd also recommend, strongly, that an engine NEVER be stored with oil that's seen more than a couple of hours run time.

And last, I haven't used dino oil for more than a decade in any car i own, and don't recommend it to anyone unless you have a car with a major leak or other high consumption issue.

[copper]

Wasn't my intention to store it dirty. Just happened that way...

We've used synthetic for last 16 years, but consumption got to about 2 liters/500 km last summer. Just fixed some top side major leaks in the breather housing, pressure sender and thermostat.

Now onto the drain plug washers, sumpgaskets, new valve covers and gaskets, pressure relief valve washers, etc...

I'm gonna give dino a shot and see how things are after that. There seems to be a conflict of opinion regarding synthetic causing leaks, or increasing occurrences.

It's a 69T with a stock 2.0 so I don't figure it'll be a problem running dino.

[randywebb]

fastpat's ideas are generally good. but it won't kill anything to store it for a while with 'contaminated' oil or to run dino oil in it. consider that before synthetic was invented, these engines ran many many miles on dino oil. sometimes we get just a tad too anal. tho i know that anal and porsche owner don't really belong in the same sentence...

[fastpat]

Originally posted by copper
Wasn't my intention to store it dirty. Just happened that way...

We've used synthetic for last 16 years, but consumption got to about 2 liters/500 km last summer. Just fixed some top side major leaks in the breather housing, pressure sender and thermostat.

Now onto the drain plug washers, sumpgaskets, new valve covers and gaskets, pressure relief valve washers, etc...

I'm gonna give dino a shot and see how things are after that. There seems to be a conflict of opinion regarding synthetic causing leaks, or increasing occurrences.

It's a 69T with a stock 2.0 so I don't figure it'll be a problem running dino.

With that high level oil consumption I'd go with the most cost effrective quality oil until it's reduced, which appears to be your plan.

Keep in mind that many if not all detergents in mineral (aka dino) oils are synthetic base stocks used in the formulations of synthetic oils, so you're getting some of the benefits of synthetic with mineral oils.

Dusting off my old Porsche memories, isn't your engine one with a magnesium/aluminum alloy crankcase If so, that alloy is very susceptable to corrosion caused by acids formed in the lubricating oil from byproducts of the combustion process, so I'd say be extra careful.

Pat

[kach22i]

HOT - HOT - HOT

As I was told, there is a thermostat valve which opens up when the engine is hot. This allows the oil to go through the front Trombone cooler or front oil cooler depending on your year or set-up.

There is at least 2-Quarts of oil in the front lines and cooler - this estimate is based on my actual experiences.

Cheers - no pain no gain.

[M.D. Holloway]

If you replacing seals, the synthetics will do fine. The older seal technology tended to leak when in contact with the PAOs (synthetics), today, the seals are far better at their resistance to synthetic oils. Synthetics will provide more thermal stability and are more resistant to oxidation than the mineral based oils. I have a synthetic blend in mine and wouldn't use anything else.