Kent-Moore Tool Company sells a dynamic timing meter for diesel engines that have dual pick-ups. One pick-up measures the pressure impulse in the injection pipe and the other pick-up measures luminosity. Luminosity is measured by screwing a probe into the glow plug hole.
The timing specifications for Buick produced diesel engines are based upon using the luminosity pick-ups that are available in such meters as Snap-On, Kent-Moore, Owatonna and Sun. Any other type of device that measures something other than luminosity will not correlate with the specifications and should not be used.
General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.