What is the required reservoir pressure for measuring stroke with the engine off?

The required reservoir pressure for measuring stroke with the engine off is indeed 90 to 100 p.s.i. This pressure range ensures that the system has adequate hydraulic pressure for precise measurements without the influence of engine vibrations or other operational factors. This range enables the tools and measurement devices used to accurately assess the stroke while ensuring that the hydraulic components function within their optimal pressure ratings.

Using a pressure that is too low may lead to inaccurate measurements due to insufficient force to engage the measuring devices fully. Conversely, exceeding the recommended pressure could risk damaging the measuring instruments or create hydraulic system stress. Hence, the 90 to 100 p.s.i. range is ideal for accurate and safe readings.