Porsche 911 Long-Hood „Ölklappe“ Buyer's Guide

Function: The flap on the right-hand B-pillar served to fill the dry-sump oil tank, which was placed in the right rear wing for better weight distribution.

The problem: It resembled the fuel filler flap. Careless attendants put petrol into the oil tank, and the result was a destroyed engine. That is why the solution was dropped again in 1973.

Authenticity check:

• Is the flap original? Retrofits can be recognised by untidy welds or by the texture of the paint
• Compare the chassis number (VIN) with the production records. There are forgeries built on other model years.

The body corresponds to the long-wheelbase long-hood 911, but the oil flap gives it a unique selling point. Corrosion is the main enemy.

• The area of the oil flap: check the metal around the flap and the oil tank behind it for corrosion. The mechanism must be intact (original parts are scarce)
• Battery boxes: two batteries were often fitted at the front; check for acid damage
• Sills and floor panels: corrosion spreading from the inside out. Lift the carpets.
• Wings and headlight bowls: the classic weak points
• Targa: check the seals and the roll bar

Some of the 2.4-litre engines (2,341 cc) used die-cast magnesium for the crankcase. Lighter, but more prone to corrosion and distortion.

• Magnesium case: cracks or pulled cylinder head studs are serious, expensive damage (case repair: €3,000-€8,000)
• Oil leaks: Seals, oil return tubes (resealing: €500-€3,000)
• Chain tensioner: Conversion to the hydraulic Carrera tensioners is recommended (cost: €800-€1,500)
• MFI (E and S): the Bosch injection system is complex. Worn pumps or throttle bodies cause poor running (pump overhaul: €1,500-€3,500)
• Heat exchangers: often rusted through (a smell of exhaust). Stainless steel is recommended

With model year 1972, the type 915 gearbox was introduced. It replaced the 901.

• H-pattern: first gear forward and to the left (instead of the dog-leg of the 901)
• More robust: laid out for the higher torque of the 2.4-litre engines
• Shift quality: a little notchy when cold (normal). A crunch on the shift points to worn synchromesh rings (second and third). Overhaul: €2,500-€5,000
• Shift linkage: the bushes develop play and the shift becomes imprecise

Agile handling, but maintenance is essential for safety.

• Rubber bushes: they age and make the car feel vague. Replacing them is involved (a set: €300-€800 plus expensive fitting)
• Dampers: a wear part (Bilstein/Koni)
• Hydropneumatic suspension (911 E): optional. The system is complex and expensive, and is often converted to conventional springs
• Brakes: seized callipers after standing, corroded lines
• Wheels: original Fuchs wheels (check their condition)

Electrics:

• The wiring looms become brittle
• Long-wheelbase specific: two batteries at the front; check the body for acid damage
• Instruments and alternator: failures due to age

Interior:

• The dashboard often cracks in the sun (repair: €500-€2,000)
• Seats: sagged or worn. Original coverings (houndstooth or corduroy) are valuable
• Door trims: they warp with damp (check the moisture barriers)