General

Winterizing Procedures and Tips

<< ... What is the best way to winterize my vehicle? Any info would be
greatly appreciated! ... >>

I've used the following procedure for years without trouble. Note that some guys pull the plugs and drop some oil in the cylinders but I've never had any trouble not doing that on the 928 (now, motorcycles are different ...)

1) Add a fuel stabilizer - I believe the brand name "Sta-bil" is the standard. I've heard different recommendations on how full to keep the tank but try to keep at least a half-tank full of gas. Add appropriate amount of stabilizer.
2) Remove battery. Keep in warm place and charge periodically
3) Plug engine air intake and exhaust openings with steel wool - you don't want mice creating a nest in your air filter box
4) Good exterior washing - make sure good and dry before storing. If storing indoors then use a flannel car cover (it breathes). I'm not sure what to recommend for outdoor storing.
5) Relax doors, hatch, and wipers. This is to avoid compression of the seals. Shut doors to first stop position. Put a wood block under your wipers to keep off the glass.

That's basically what I do before storing. In the spring I get the oil and coolant changed as soon as I can. I also change brake fluid every other year.

Starting it the first time in the spring used to be a problem for me before I bought a good battery charger with a 50 amp starter in it. I charge the battery good before replacing it in the car and then I start the car with the charger hooked up. That is, I flip the switch on the charger for the "start" mode and start the car. It starts right up - and what a wonderful feeling that is too :-)

Mike McQuaid
94 928 GTS blue/tan auto


It is advisable to change your oil prior to storage to eliminate the acids which build up in the oil during use. If the oil is changed prior to storage, there is no need to change it in the spring. This is the recommended procedure by M/C service shops - and they know a lot about winterizing motors.

Steve -87S4/auto/GPW


One thing that has not been mentioned is putting a few extra pounds of
air into the tires. Check out:

http://www.porschenet.com/winter.html

-- David Chamberland
91 928GT (Amazonagrunmetallic: Green. NO! Blue! Ahhhhhhhhhhh!)


I've noticed the recent inquiries and responses to "winterization" questions
for the 928 and thought I'd offer an unsolicited comment. Within the past week
I have been made rudely aware of what *not* to do for engine care during the
winter. It may or may not apply to the 928. Just use it as additional
information to add to your knowledge base. I live near Portland. Oregon where
the winters are not particularly cold, but do tend to be damp, rainy, and
foggy at times.

Here is what happened. I also have an airplane which resides in my garage with
the cars. The garage/hanger is mostly unheated. I fly some during the winter,
but not a lot. I always fly enough to heat the oil when I do go out. A few
years ago, I began using Aeroshell 15W-50 semisynthetic aircraft engine oil.
Reasons were the usual ones for using synthetic based oils, and I noticed
immediate reduction in cylinder head temp, smoother operation, reduced fuel
consumption, etc. I have all digital engine gauges including fuel flow which
is accurate to 0.1 gph so these improvements were actual, not seat of the
pants feelings. I changed the oil at regular intervals - less than the
recommended time. The Shell semisynthetic is especially formulated to inhibit
corrosion. At least that is what the Shell specs say. Conforms to FAA specs.,
Mil-Spec., engine manufacturers approvals, etc., etc. Supposedly, the best
money can buy.

One cylinder was down on compression due to a leaking exhaust valve so I
removed it for repair. What I found was not pretty. Rust pits!! Rust on the
cam. Rust on the can followers. Rust on the piston pins. Rust on the inside of
the cylinders. I have not removed a rod cap to check the crank, but I fear the
worst. These rust pits are through the hardened surface so service life will
be short and the engine must be removed, torn down, and all rusted corroded
parts replaced. The basic engine overhaul cost is estimated at $14,900. That
is with me removing it, and re-installing it. No accessories like carb,
magnetos will be touched for that price. If the crank is bad, add another $6k
to $8k.

The engine shop said, "We see that all the time when people use synthetic oil
and don't use their machine regularly. The synthetic flows off the internal
parts and leaves them open for condensation moisture attack". They recommended
to only use synthetic oil if the engine will used continually. If it will not
be used much during the winter, use regular, non-synthetic, oil; something
that will stay on the surfaces. Here I thought I was doing all the right stuff
to take the best care of the thing and It was not right at all. Wish I had
known then what I know now. |:(

I guess it doesn't matter much, but wear on the parts, excluding corrosion,
was nil with about 800 hours on the engine. This may not apply to auto engines
or auto engine synthetic oil, but it seems like it shouldn't be too far off.
If you live where condensation is not a problem, ie. dry and usually below
freezing, then this probably wouldn't be a factor. Yes, both the 928s still
have Redline oil in them, but will be used regularly. As always, YMMV.

Back to the garage now to spend my Sunday afternoon removing cooling baffles,
exhaust pipes, and lots of other stuff.

Louis Ott
'86 S auto
'88 S4 stick