924Board.org

[Gatornapper]

As we all know the Series 1 Turbos (mine) had problems due to the oil-only cooling of the turbo-charger, well described by Stuttcars.com thusly: "A turbocharger cooled only by engine oil led to short component life and turbo-related seal and seat problems. "

My turbo seems to be running well with no problems. 60+ k miles on car. I'm running VR-1 Synthetic and always cool the engine down with a minute or so of idling before shutting it of. Additional good news is the drive from the paved road to my house in the woods is 1/2 mile long which is traveled in 2nd gear at idle speeds - so the turbo is always cooled down some before I get home. And with new water pump, t'stat and coolant, my engine is happily running cool even on hot days.

What PM should I be doing to my turbo? What "turbo-related" seals and seats do I need to be concerned with?

One thing I fail to do. The owner's manual says that on every single drive, floor the engine in first gear to 5500 rpm the keep the waste gate from rusting shut. I rarely remember to do that. Will doing it in 2nd gear work?

As always, I have too many questions.

TIA,

GN
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'87 944 S, looks & runs like new - sold my sweet 931; '76 914 2.0 mostly restored; 2011 Porsche Cayman S in Meteor Grey, 3.4L, Softronics ECU tune 355+hp , PDK w/Sport Chrono. Got this thing for Porsche's.......

[Carrera RSR]

[Gatornapper]

THANK YOU THANK YOU THANK YOU!

This is REALLY good news and makes total sense. I am a stickler for Synthetics (using in all vehicles since 1977), regular maintenance and warming up and cooling down. Oil cooler is clean & cooling system new as I said.

My seasoned prof. mechanic son drove my 931 last nite for first time and after .7 mile at 15mph, stepped on the turbo....."NO, NO, NO!" shouted Dad....."Get it warmed up first!" - even tho temp gauge was about 1/3 of the way up.

Problem is I don't know what P.O. did who owned it from '85 to '21.....with the last 17 years of that in good storage.

Another question: With VR-1 Synthetic 20W50, how often would you change the oil? I don't get on the turbo that much, only once-in-a-while.

GN

[Fasteddie313]

Anytime you hit full boost the wastegate will open and close..
What it says about first gear is it just wants you to exercise the WG once in a while..

Just hit full boost once in a while.. Same same..
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80 Turbo - Slightly Modified

[peterld]

Oil changes?

Road car : every 5000 kilometres

Race car: every meeting.
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80/81 932/8 ROW

[Gatornapper]

Do that!

Thanks Eddie.

GN

[Gatornapper]

Peter -

3k miles is normal for conventional oils.

Can't I stretch that safely to 5k miles with full synthetic? How about with a new oil filter every 2,500 miles?

GN

[kondzi]

I always wonder where's the magic as modern cars have scheduled oil change i.e. every 15 000 - 20 000 km. My father is buying a new Ford Kuga - first oil change according to service after 20 000 km... or a year. I will change it after 1000 km and then after 5000 and then I don't know.

With the older cars as we are all interested in, I do the break-in using mineral oil and change it after c.a. 100km. Then again same story after additional 500km. Then I switch to synthetic and keep to 5000km / 2 years (I drive little with these cars, so usually 2 years is c.a. 5000 km). But maybe I'm so wrong?
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Konrad
'89 951 US
'88 Mustang 5.0 LX Convertible (factory specs)
'84 911 Carrera 3.2 RoW (factory specs)
'81 931 RoW (TBD)
'81 Ford Capri 2.8i (factory specs)
'79 Ford Capri 2.9 (heavily modded)

[peterld]

Oil and filters, no matter how expensive, are still cheap in the great scheme of things.
All my vehicles get synthetic, no matter the age of the vehicle.
Fresh oil is cheap insurance, and besides I must dissect the filter......that's the proof of the pudding.
Certainly new car oil changes are ridiculous, but sooner oil changes are the owner's choice.
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80/81 932/8 ROW

[Beartooth]

Well, you're never going to hurt anything by changing the oil too often. Mostly it's just a question of whether spending more money on oil changes extends engine life enough to give a return on that investment. New cars are generally easier on oils because of roller valvetrains and better piston ring sealing (apparently direct injection has reversed that though).

I've taken to changing oil twice a year on the two vehicles I mainly drive. That usually works out to 3-5000 miles. I could probably go farther. I do mostly highway driving, and live in a dry climate, so I'm not worried about moisture build up, but I have enough cold starts and occasional hard driving that I think it makes sense not to try and push it.

I like synthetics, but I don't think the value is automatically there. I typically run synthetic in my truck in the winter because it helps it start and probably makes a difference in wear while the oil is cold, but I switch to conventional or semi-synthetic in the summer. That takes 14 quarts though, so we're taking about $50 more for synthetic. I'm thinking about adding an oil heater and just running conventional year round. Now, for a car that's driven hard, one that you're looking to squeeze every last drop of performance out of, synthetic is a natural choice. On the other hand, cars that are only occasionally driven and don't see severe use will probably benefit more from conventional oil and more frequent changes. For those just looking to get the most miles per dollar spent, you can use engine oil analysis (I use Blackstone from time to time, more to monitor engine condition) and extend oil change intervals based on their recommendations. Of course, that takes some up-front investment that'll take a while to pay off in extended oil changes.

I'm new to the 931, but my plan is to run the best oil I can find without getting exotic. The oil-cooled turbocharger, especially with the feed line exposed to the exhaust manifold, is a recipe to break down lessor oils. I wonder if a lightly-driven 931 would be hard on oil too, but maybe "lightly-driven 931" is an oxymoron. One of the most important thing is that, like the Mercs I'm used to, they use solid tappets/cam followers, which live longer with more zinc and phosphorus. I tend to gravitate toward Mobil because they're easy to find and they list their zinc/phosphorus content; there are other good oils, obviously. M1 15W-50 has the most, and is what I run in the Mercs in the summer. For winter, I use 5q 0W-40 and make up the other 3q I need with 15W-50 to bring it up a bit (0W is probably a little light for an older engine with 200+k miles; FSM only references down to 5W).

So anyway, since it's easy to find here, would M1 0W-40 FS make a good choice? It's Porsche A40 and ACEA A3/B4 rated... I guess my thought is to see how it works, but go heavier if I find too much oil consumption. Not sure how much oil weight the engine really needs, but there's also the issue of what's ideal for a new motor vs. one with worn rings and bearings.
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1980 931 diamond in the rough

[jacobroufa]

I've run nothing but LiquiMoly 20W-50 in all my vintage cars and have been very happy with annual changes. I linked that to RockAuto's page for that oil, as they've got an excellent price on it (as well as pretty much all wearables)...

1963 VW Beetle sedan, 1980 931, 1981 924, 1981 VW Vanagon are all quite content with this oil in my experience.. Maybe I should give Blackstone a whirl and see how they actually fare? That's a neat thought.

Here is the MSDS for the oil I use as well, to compare to M1 if you want.
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1980 Porsche 931
1981 Porsche 924 Weissach

[Beartooth]

I've never used it myself, but that sounds like a pretty good oil. I lean towards synthetic, partly because I live in a climate where it can get pretty cold. I think synthetic is worth the price in damage prevented from frequent cold-cold starts (like well below freezing). I don't have the garage space to keep my drivers inside for the time being, so that's part of the equation. I couldn't find any cold pour point or cold viscosity information; it'd be interesting to see how that compares to something like M1 15W-50.

You can go pretty far down the oil analysis rabbit hole. I try to send a sample in occasionally, but don't think it's worth the cost to do one every time. Other than when I get a new-to-me car though, it usually ends up being a couple years between samples. The guys who use it most are truck drivers and industrial operators, where the cost of a sample is nothing compared to an oil change (when the oil quantity is measured in gallons). Even one sample can give you some useful information though. Depending on the engine, they can give you some idea of where you're at by comparing to what they see from similar engines. Some people put too much stock in it, and you may need a few tests to get an accurate picture, but it's definitely a cool tool to look at how your engine is wearing, and how your oil is holding up.
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1980 931 diamond in the rough