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  4. Drainage Pipes

Drainage Pipes

Drainage pipes are plastic pipes which are usually found as part of a sunroof system, although they can also be found on some convertible hood drainage systems.

Replacement drainage pipes
A set of silicone replacement pipes next to a set of blue factory fitted pipes. Replacement pipes are often better quality than the stiffer ones fitted at the factory.

These drainage pipes are not very thick and so prone to blockage from leaf litter which may find its way into the sunroof cassette. 

Like many plastic parts, they are prone to shrink and harden over time. As they usually don't follow a straight line, the shrinkage may cause them to pull on places where they bend, causing them to be squeezed or pinched. Eventually, they may shrink so much that they pull off their connectors and become disconnected. The nylon connectors may also become brittle and shatter over time. These are not high-stress parts, so the hoses just press fit onto connectors and aren't particularly tight, so if they get a crack, they can easily fall off. One of the biggest problems we see with these pipes is that we find somebody has tried to repair them by glueing them back on. This just leads to a pipe which is stretched and constricted, and harder to remove.

Replacement drainage pipes are usually not too expensive, and we often find that the replacements are an improved design or better quality than the originals.

Sunroofs usually have two of these pipes at the front, although larger sunroofs may have an additional two at the back of the cassette. Some convertible cars also have pipes to drain the rear scuttle.

Written by . Last updated 27/10/2023 15:35