Remove the EGR valve spindle guide

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Remove the EGR valve spindle zjautoparts.net guide—when engine equipped with press fitted guides, old guide can be pressed out and new replacement pressed in. Worn guide can be removed with driver and ball peen hammer or press like arbor press. Whether use hammer or press, should use special drive tool to remove old guide. These available from engine manufacturer. As substitute for driver, piece round metal almost same diameter as valve guide can be used. Don’t want to use driver exactly same diameter as guide because driver can be pressed into engine as drive out guide. When driving out old guide, be sure engine supported so won’t move. Few small blocks wood under engine will provide support. Even though press or driver can be used on most engines, should check service manual for recommendations.

Inspect the bore—after removed old guide, use solvent to clean bore in engine where guide located. Visually inspect guide bore for deep scratches or signs physical damage. If such conditions present, new guide may not fit tightly enough. If bore damaged, replacement guide will need to be slightly oversized (if its outside diameter will need to be larger than outside diameter old guide). If have replacement guide large enough, be able to correct damaged bore by reaming to fit oversized guide. Remember that oversized guides not available for all engines, and some engines won’t have enough metal around guide bore to allow for enlargement. Only choice then to replace block or cylinder head (whichever part contains guides).

Insert the new guide—once guide bore in good condition, ready to install new guide. New guide must fit very tightly in guide bore. To make inserting tightly fitted guide easier, leave in freezer for hour or so. Cold will cause guide to shrink. Once shrunk, remove from freezer and insert in engine.

Driver with ball peen hammer or arbor press can be used to install new guide. Because cold guide shrunk, should slide into guide bore easily. When insert guide, be sure is placed in proper position as described in service manual.

Need to ream out newly inserted guides to meet specifications. New insert will have smaller inside diameter than necessary. Inside diameter must be enlarged to match valve stem. Enlarged using reamer, a long round cutting tool with cutting edges along length. Tool operates like drill bit, however doesn’t cut with end or point. Cutting surfaces along sides.

Can’t use drill bit for enlarging guides diameter for two reasons. Reamer can enlarge with more precision than bit. Few thousandths of inch will make big difference to operation engine. Also, drill bits not available in exact sizes guide holes. Reamers designed for inside diameters valve guides can be purchased from engine manufacturers. Some reamers adjustable to accommodate almost any size hole.

To use, reamer inserted into hole, turned clockwise until penetrates length of guide. Reamer can be operated by hand or electric drill. Should always be turned in clockwise direction. Turning in opposite direction will dull edges. Even when backing reamer out of hole, continue turning clockwise.

Appropriate inside diameter valve guide depends on size valve stem. Service manual for engine usually specifies diameter. Generally hole should be reamed to size between 0.002 and 0.004 inches larger than diameter stem.

Some Valve seat zjautoparts.net don’t have material around guide to permit reaming. Consult service manual to check procedures for any engine. Once guide reamed, metal particles should be removed with compressed air and area washed with solvent.