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Bulletin # 04 of 2011

Interior Title: 
Bulletin # 4 of 2011
Title Type: 
Caution Bulletin
Bulletin Date: 
Bulletin # 4 of 2011. June 8, 2011
Bulletin Type: 
Caution Bulletin
Bulletin Subject: 
Diaphragm Part Number 510-553
Products Affected: 
(Possibly) Regulator Diaphragms p/n's 510-553, 500-010, 500-011, 500-040, 500-041, 500-050, 500- 051, 500-100, 500-101, 500-025, 500-026, 500-028, 500-029, 500-599, 500-600, 505-069, 505-069NS, 505-027, 505-026, 525-309, 525-317, 525-319, 525-322, 525-323, 525-325, 525-327, 525-333, 525-341, 525-345, 525-347, 525-349, 525-360, 525-363, 525-365, 525-358, 525-381, 525-382, 525-388, 525-327, 305-175, 325-325 (Shipped January 23rd, 2009 through December 2010).

A questionable fit with several regulator diaphragms, (p/n 510-553), was reported when being replaced during routine
For inspection reference, these diaphragms can be visually identified by the smooth shiny appearance of the rubber.
Earlier production batches of this part showed more of a satin, dull finish and have not exhibited any fit issues and do
not require this measurement inspection.
It is recommended that all spare parts be inspected for this condition This includes spare regulator diaphragms, the
505-069, 505-027 and 305-175 regulator assemblies as well any helmets and masks that use the SuperFlow Regulators.
Only diaphragms with a shiny finish need inspection.

A simple, quick inspection can be performed using a #53 (0.0595" (1.52mm)size drill bit  as an inspection gauge. Make
certain the diaphragm is in a settled condition on the sealing shelf (flange) of the regulator body. There should be no
clearance between the outer edge of the diaphragm and the flange of the regulator body with the gauge in place. The
best method to check the O.D is to use an accurate measuring device such as vernier calipers or a micrometer. The O.D
should measure no less than 2.905" (73.79mm). Any parts showing less than this dimension, or a larger gap when using
the gauge, should be replaced.

Diaphragms not passing inspection can be returned at no charge through an authorized KMDSI dealer.

Caution Bulletin 4 of 2011

Note: With the gauge in place, there should be no additional gap between any of the parts.

For further information, contact your authorized Kirby Morgan® dealer or [email protected]