Corvair Pressure Plate clearance measurements.

page 32.

. To be sure your pressure plate will give good service when installed, check to see that the clearances are up to specs. This is a measurement you can make with just a straight edge and feeler gages. . Measure as shown in photo below from the straight edge down to clutch disc contact surface; measure in six places to see if measurements are consistent (they should be).

Type of pressure plate: ................... measurement and variation: .1960-1963 (non-turbo)..................... 0.190" (+/- 0.010") .1962-1963 turbo (Spyder).................0.185" (+/- 0.015") .1964-1969 non Corsa........................ 0.084" (+/- 0.007") .1964-1969 Corsa (140 & 180hp)......0.095" (+/- 0.007")

. These measurements are based on a survey of a large group (25) of used (unaltered) and nos factory original pressure plates. . When rebuilders decide to remove material from the iron face, they should insert a one piece stamped shim behind the new diaphram spring before they re-rivet it in place (see photo below). The shim should be the same thickness as the material the rebuilder removes from the clutch contact surface.

Shim that should be provided if iron has been machined off face.

. One final thought about clearances has to do with clutch disc thickness. In a Corsa Communique article, Mark Domzalski notes that " A correct rebuild for Corvair is 0.290" to 0.335", with 0.330" ideal." This is the thickness with the disc lightly clamped together (there is a wavy spring inside that should be compressed before this measurement). . If the pressure plate, clutch disc, and flywheel dimensions all check out, you will probably have a successful clutch job.

Diaphram spring.