105400-4121 ZEXEL 9 420 612 485 BOSCH GOVERNOR 9420612485 1054004121 8944501070

FEED ENGAGED
21. Slot. 22. Pin. 23. Knob. To set the feed mechanism into feed on later units, turn lever (A) up (the direction of arrow).
LATER FEED MECHANISM
A. Lever.Place adapter (24) into boring bar and tighten setscrew (25).
ADAPTER INSTALLED
24. 1P2364 Adapter. 25. Setscrew.Apply layout bluing to the bearing cap and bearing bore. Oil the centering rings. Do not use lubricant on the cutter. Use a one-half inch electric drill with universal joint (26) to feed tool through the bore. Service main bearings with .010 in. (0.25 mm) oversize outside diameter are available to permit the bore to be bored oversize. Bore the bore to 3.7175 .0005 in. (94.425 0.013 mm).
BORING BEARING BORE
26. 1P2363 Universal. If you use the later feed mechanism, the tool can be driven from either the boring bar or the feed mechanism.
DRIVING THROUGH FEED MECHANISM (Typical Example)
26. 1P2363 Universal.The bluing applied to the bearing bore indicates the condition of the bore at the correct bore size. If bluing shows an out of round condition, check the largest diameter (indicated by remaining bluing) in relation to the smallest diameter (indicated by lack of bluing). The difference of the two must not exceed .0010 in. (0.025 mm).If bluing indicates a step in the joint face, measure the diameter at the step in relation to the smallest diameter. A step of .0005 in. (0.013 mm) on one or both sides is permissible. A maximum of .0010 in. (0.025 mm) over the nominal finish bore diameter is permissible if within the described limits.To check the bore diameter, set the 1P3535 Dial Bore Gauge to 3.7175 in. (94.425 mm).
CHECKING BORE (Typical Example)Line Boring Main Bearing Bores
Line bore all main bearing bores if bearing caps or saddles are distorted.Clean bearing caps and saddles. Remove all nicks from pan rail. Plug oil holes in block with grease to prevent chips from entering oil passages.Place 1P2344 Centering Rings (1), with oiler (2) up, at each end of block. If an end bore is distorted, use the next good bore. There must be two good bores for locating centering rings.
CENTERING RINGS IN BLOCK
1. 1P2344 Centering Rings. 2. Oiler.Place original bearing caps (4) over the centering rings (1). Tighten bolts (3) hand tight.
CENTERING RINGS INSTALLED
1. 1P2344 Centering Rings. 3. Bolts (four). 4. Bearing caps.
BORING BAR INSTALLED
1. 1P2344 Centering Rings. 3. Bolts (four). 5. 1P2352 Boring Bar.Oil boring bar (5) and insert it through centering rings (1). Tighten bolts (3) to a minimum of 20 lb. ft. (25 N m) and a maximum of 50 lb. ft. (70 N m) while spinning boring bar (5) to check for binding. Centering rings (1) must be seated in bearing saddles after tightening.Slide boring bar (5) out of one end of block and install bearing assemblies (6) on boring bar (5). Slide boring bar (5) back through centering ring. Adjust bearing by tightening bolt (7) until bar begins to bind, then back off until boring bar (5) spins easily.
INSTALLING BEARING ASSEMBLIES
5. 1P2352 Boring Bar. 6. 1P2373 Bearing assembly