Ford — Spark Plug Thread Service (Taperset Installation)
Repair & overhaul · Cylinder head
From a Ford service manual — check it applies to your exact model before use.
Browse Ford generators & specs →
Before you start
- The cylinder head must be removed from the engine before installing a taperset; performing while on the engine will cause metal chips to fall into the cylinder.
Procedure
- Thoroughly clean spark plug counter bore, seat and threads of all dirt or foreign material.
- Start tap into spark plug hole keeping it properly aligned; apply oil as the tap begins cutting threads until stop ring bottoms against spark plug seat.
- Remove tap and remove all metal chips using compressed air.
- Coat threads of mandrel with cutting oil; thread taperset onto mandrel until one thread of mandrel extends beyond taperset.
- Thread taperset into tapped spark plug hole using a torque wrench until it indicates 61 N·m (45 lb-ft).
- To loosen mandrel, hold mandrel stationary and turn mandrel body approximately one-half turn; remove mandrel.
Tools required
- Rotunda Taperset Installation Kit 107-R0901 Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Taperset installation torque 61 N·m (45 lb-ft)
Source: Ford service manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.