How to Perform a cylinder leak test efficiently

When performing cylinder leakage tests, the following tips might be helpful:

• Remove all spark plugs to allow easier rotation of the engine. (If this test is done
after a compression test, the plugs should already be out).

• Perform the leakage test on all cylinders, not just the problem cylinder. This would
indicate any other problems which can be rectified. This eliminates any repeat
repairs and wasted diagnostic time.

• Perform the leakage test in cylinder firing order starting with cylinder #1. It takes two
revolutions of the engine to complete the leakage test. Start at cylinder #1 and
rotate the engine to the next cylinder in the firing order. Divide the number of cylinders
into 720, the result is the number of degrees that each cylinder fires.

For example,
if you divide a 6 cylinder into 720, this equals 120 degrees. If you start at cylinder
1 and rotate the engine 120 degrees in the direction of rotation, you can check
the next cylinder in the firing order. This process eliminates the need to rotate the
engine an excessive amount.

The graphic depicts an engine with a firing order of: 1-5-3-6-2-4

If leakage is found monitoring area of loss will indicate failed component.

For example, excessive leakage on gauge and:
heard from exhaust would indicate a failed exhaust valve.
heard from intake manifold would indicate failed intake valve.
found in cooling system would indicate failed head gasket or cracked cylinder head.
heard in dipstick tube would indicate faulty piston rings.

 

Porsche History – Part 4

In the 1950s the bodies for the Porsche 356 were built and fully painted at the Reutter factory and then delivered with windows and interior equipment. Porsche subsequently undertook fitting of the engine and running gear. In 1964, Porsche purchased the Reutter carbody factory. This meant that for the first time Porsche was in possession of an independent automobile factory.

In 1969, vehicle assembly moved into the newly built multistory building on Schwieberdinger Straße. At that time, vehicle interior equipment was fitted on the third floor. Installing the engine and bolting together the running gear followed on the second floor.

In 1979, a second production line was introduced for the production of the Porsche 928.

This was the first time that a hanger system was used in running gear installation, which was adopted for the Porsche 911 a short time later. At the beginning of the 1980s, Porsche converted to movement on skids on the third floor. The assembly process was still executed on a static vehicle. However, at the end of the cycle assemblies were forwarded automatically within the respective production section. In the meantime, production technology at Porsche has been developed further so that the Boxster and 911 are now both assembled using the mixed-model system on a continuous line.

Since 1987, bodies welded previously in the main plant have been transported from a newly erected body shell production site over a bridge to the paint shop and then fed to the assembly hall.