It usually starts with very small parts flaking off the slowly decaying seals. Sludge in the hydraulic system is formed by very tiny, oxidized particles. Lots of sludge in the system turns into an abrasive paste that will accelerate the formation of more sludge simply by grinding on the cylinder walls, and that changes the chemistry of the fluid a little. It is very rare that the abrasion on the cylinder walls is seriously threatening the longevity of the cylinders - the main problem lies in plugging the pump, wearing the pump pistons, and accelerated decay of the original seals in the hydraulic cylinders.

I have seen ten year old systems with perfectly clear fluid in them, and five year old systems that were a mess. The main factors are climate and amount of use. Hot environments accelerate chemical reactions. The original seals in the cylinders hydrolize and oxidize. Nothing can stop that. Top Hydraulics' seals are many times less sensitive to environmental factors, which makes me extrapolate our useful seal life to some 30-50 years in most cases.

In extreme cases with a lot of humidity in a hot climate, there will also be condensation inside the reservoir as the fluid level changes. Water in the fluid is bad news. There is a little room for water to accumulate on the bottom of the Crossfire pump reservoir, but not much. An important characteristic of the roadster top hydraulic fluid is that it does not suspend water in it. It makes water sink to the bottom of the reservoir. Having a mixture of steel and aluminum in the hydraulic system, water inside the cylinders can wreak havoc, if it ever makes it that far.

There is nothing wrong with using your top a lot. Just flush your fluid every three to five years in hot & humid climates to every ten years in mild climates. As I said, I will address a possible fluid flushing procedure in a separate post (as time permits).

Klaus

Top Hydraulics | Rebuilt and Upgraded Convertible Top Cylinders, Pumps, Hydraulic Lines - Top Hydraulics, Inc