Valve Guide Servicing

Check valve stem-to-guide clearance, and if clearance exceeds service limits, replace valve guide with next oversize component. Guides are available in the following oversizes:

VALVE GUIDE OVERSIZES

Size Mark	Guide Size	Cyl. Head Bore
5	.002" (.05 mm)	.5138-.5145" (13.05-13.07 mm)
25	.010" (.25 mm)	.5216-.5224" (13.25-13.27 mm)
50	.020" (.51 mm)	.5315-.5323" (13.50-13.52 mm)

VALVE STEM-TO-GUIDE CLEARANCE

Valve	Standard Dimension	Service Limit
Intake	.0012-.0024" (.031-.061 mm)	.004" (.10 mm)
Exhaust	.002-.0035" (.051-.089 mm)	.006" (.152 mm)

Fig 1: Rocker Arm and Valve Assembly

Courtesy of CHRYSLER GROUP, LLC

Fig 2: Valve Guide Installation and Height

Courtesy of CHRYSLER GROUP, LLC

Heat cylinder head to approximately 480° F (250° C), and using a suitable valve guide tool, drive out each guide toward combustion chamber. Ream guide bore in cylinder head to specified size after head has cooled to room temperature.
To install new guides, reheat head to same temperature as for removal. Quickly drive guides into head. See Fig. 4. Guides should protrude 0.539 - 0.563" (13.7 - 14.3 mm) above head surface when properly installed. Check guide I.D. and ream as necessary.