Green + Red + Blue PLASTIGAGE - Assorted Pack of 3  SPR-1 + SPG-1 + SPB-1

This listing is for a pack of 3, brand new, green, red, & blue PLASTIGAGE clearance indicator threads for use in measurement of clearance in automotive engine bearings.  A measurement scale is printed on the included Plastigage package.  The thread is composed of a compliant plastic material, and is approximately 12 inches long.

Note on Clearance Sizes:  Green PLASTIGAGE is suitable for clearance requirements in the range of .001-.003 inches (.025 to .076mm), Red PLASTIGAGE covers a range of .002-.006" (.051 to .152mm), and Blue PLASTIGAGE covers .004-.009" (.102-.229mm).  This listing includes (1) each of green, red, and blue Plastigage. 

Reference on Clearance Ranges of different Plastigage Colors:

Green: .001 to .003 inches (.025 to .076mm)

Red: .002 to .006 inches (.051 to .152mm)

Blue: .004 to .009 inches (.102 to .229mm)

Yellow: .009 to .020 inches (.23 to 0.51mm) - (NOT included in this assortment)

Tech Tips on Use:  Remove the engine oil pan to reveal the big-end and its retaining set-screws. Remove excess oil and release the big-end shells by unscrewing the set-screws. Apply a smear of grease to the journal and small quantity of silicone release agent to the shell.

Trim a length of PLASTIGAGE to fit across the journal using the grease to hold it in place. Replace the shell and tighten the set-screws to the recommended torque setting, without rotating the journal.  Now remove the shell to reveal the PLASTIGAGE which will have been spread across the bearing surface as a stripe or band. Match the width of the stripe against the calibrated gauge on the package, and read the clearance.

The PLASTIGAGE stripe ideally should be removed with a clean oily cloth or degreasing solvent.  However, any remaining PLASTIGAGE residue left behind will simply dissolve in motor oil and will not harm the engine in any way.