Elbow Seal Terminal  sleeve  assembly Protector cap 5mm ferrule 7mm sleeve 5mm ignition cable 5mm ferrule 5mm ignition cable For distributor blocks with 5mm wells For distributor blocks with 7mm wells Figure 4-47.  Replacement procedure for ignition lead terminals.  2.  Loosen the piercing screw in the distributor block for  the lead to be replaced, and remove the lead from the  distributor block. 3.  Remove approximately 1 inch of insulation from  the distributor block end of the defective lead and  approximately 1 inch of insulation from the end of  the replacement cable. Splice this end to the end of  the lead to be replaced and solder the splice. 4.  Remove the elbow adapter from the spark plug end  of the defective lead, then pull the old lead out and  put the new lead into the harness. While pulling the  eads through the harness, have someone push the  replacement lead into the ignition manifold at the  distributor end to reduce the force required to pull the  lead through the ignition manifold. 5.  When the replacement lead has been pulled completely  through the manifold, force the ignition lead up into  the manifold from the distributor block end to provide  extra length for future repairs, which may be necessary  because of chafing at the spark plug elbow. 6.  Remove approximately  3 ⁄ 8  inch of insulation from  the distributor block end. Bend the ends of the wire  back and prepare the ends of the cable for installation  into the distributor block well. Insert the lead in the  distributor and tighten the piercing screw. 7.  Remove approximately ¼ inch of insulation from  the spark plug end of the lead and install the elbow,  integral seal, and cigarette.  [Figure 4-47] 8.  Install a marker on the distributor end of the cable to  identify its cylinder number. If a new marker is not  available, use the marker removed from the defective  cable. Replacement of Ignition Harness Replace a complete ignition harness only when the  shielding of the manifold is damaged or when the number  of defective leads makes it more practical to replace the  harness than to replace the individual leads. Replace a cast- filled harness only when leakage in the cast-filled portion  is indicated. Before replacing any harness to correct engine  malfunctioning, make extensive ignition harness tests.  Typical procedures for installing an ignition harness are  detailed in the following paragraphs. Install the ignition harness on the engine. Tighten and safety  the hold down nuts and bolts and install and tighten the  individual lead brackets according to instructions. The ignition  harness is then ready for connection of the individual leads  to the distributor block. A band is attached to each lead at the  distributor end of the harness to identify the cylinder for the  lead. However, each lead should be checked individually with  a continuity or timing light prior to connecting it. 4-29