starting a car that's been in storage

[sjsmith]

I am thinking about purchasing a Porsche 924 that's been in storage for about 4 years. It has not been started during storage. The car is in great shape inside and out and the price is right. The car is in the owners garage, so I cannot do much maintenance there. Question: what should I do before putting a new battery in it and trying to start it ?

[MagicRat]

This question has been answered before in the Engineering section, but never for cars that have been stored for this long.

A lot depends on where it was stored. Inside, in a dry, well vented garage is best. In this case, not too much work is required.

If it was stored outside, or in a damp building, your situation is much worse.

Also, it's worse if the car was not prepped for storage.
If the car was prepped, with oil - fogged cylinders, and a full gas tank full of fuel stabilizer, stored in a dry garage, probably a battery is all you need.

However, lets assume the worst. What you want to avoid is to turn over a rusty engine. Doing so may cause damage: break piston rings, bend rods and valves, etc.

IMO you should do the following.
-examine the engine compartment thoroughly. Look for animal damage, especially rodents chewing wires and hoses.(Also look for aged - cracked wires and hoses). Repair any deficiencies you find.

Nothing is better than finding a mouse has chewed the fuel line, so fuel will be sprayed all over the rodent - chewed bare wires, so the car instantly goes up in flames (and burning down the building its housed in)

-Look for mouse nests around the engine, in the air filter housing, on the exhaust system etc and clean them out. Also look for nests in the interior of the car, air vents, glove box, etc.

- Remove all the spark plugs and spray lots of WD-40 down the holes. Wait a couple of hours, spray again, then, using a socket wrench on the front of the crankshaft, slowly turn the engine over by hand. If the engine really will not budge, it's seized by rust, which requires professional attention.
If it moves, rotate it about 20-30 revolutions. Do not put the plugs back in.

-Change the engine oil and filter.

-Unless the gas tank was stored full of gas with a stabilizer added, consider removing the tank, draining and safely disposing of the old gas. Then remove the access panel on the tank and taking a good look inside for rust/debris/water etc. If rust is found, try having a professional clean out the tank, or get a new one. Then reinstall and add fresh gas.
Sometimes the draining and inspection can be done with the tank still on the car. (I am not sure about this model).

-change the fuel filter too, if the tank is getting worked on.

-Check all other fluid levels, coolant, transmission fluid, clutch master cyl fluid level, etc.

-Find the fuel pump relay or fuse and remove it, so the electric fuel pump will not work. Then install the battery and use the key to spin the engine over for about 20 seconds or so.
Remember the spark plugs are not installed in the engine yet. The engine should spin quickly. This allows the engine to circulate fresh oil to all the moving parts.

-Then install the plugs and fuel pump relay and see if it will start.

-remember, after it runs, it probably will be a good idea to eventually flush and fill the cooling system, and replace all belts and hoses if they are dry, hard, cracked, etc.

Good luck.