Usage:
Early production governor housings (4N570, 6N1744 and 6N7524) did not have a bushing (1) in the outer bore for the governor control shaft. Later production governor housings do have a bushing (1) in the outer bore, as shown, but neither the early production or the later production governor housings have a bushing in inner bore (A) that is also for the governor control shaft. The procedures given in this instruction are for the use of the FT1525 Alignment Pin, FT1526 Salvage Fixture and the FT1698 Bearing Installation Tool. These tools are needed to install a bushing in the inner and/or outer bore for the governor control shaft in either the early production or later production 3208 governor housings. Use the procedure given in this instruction that is needed for the specific governor housing to be reconditioned.
1 - FT1698 Bearing Installation Tool, 2 - FT1525 Alignment Pin. Parts of the FT1526 Salvage Fixture are as follows: 3 and 4 - Machined Plates; 5 - Liner; 6 - Lock Screw; 7 - Drill Bushing and Reamer Bushing; 8 - S1591 Bolts with 4B5271 Washers; 9 - Reamer, 18.808Ø + 0.000, -0.005 (.7405"Ø, + .0000", -0.0002") High Speed Steel, 12.7Ø (0.5"Ø) Straight Shank, 143.0 (5.62") Minimum Flute Length; 10 - Core Drill, 18.26Ø (.719"Ø), High Speed Steel, 12.7Ø (0.5"Ø) Straight Shank, 143.0 (5.62") Minimum Flute Length.
It is necessary to purchase reamer (9) and core drill (10) from Mohawk Tools. The Mohawk Tools part numbers for these tools are as follows: Core Drill, CT 23/32; Reamer RT 3/4. Order the tools from the address that follows:
MOHAWK TOOLS Attn: Standard Tool Section Sales914 East Main Street
Montpelier, Ohio 43543
U.S.A.
Telephone (419) 485-3171
(1) For the CT 23/32 Core Drill, it is necessary to turn down (machine) the drill shank so it can be used in a 1/2" electric drill.
(2) For the RT 3/4 Reamer it is necessary to grind the cutting edge of the reamer to 18.808Ø, +.000, -.005 (.7405"Ø, +.0000", -.0002"). It is also necessary to turn down the shank of the reamer, so it can be used in a 1/2" electric drill.
Installation Of An Outer And Inner Bearing For Governor Control Shaft (Early Production Governor Housings That Need The Control Shaft Bore Machined)
(1) Remove seal (1) from housing (2). Remove gasket (3) and carefully file or sand the gasket face of housing (2) to remove any nicks or burrs. The gasket surface must be completely smooth and clean.
(2) Put FT1526 Fixture (4) in a vise as shown, and put governor housing (2) on fixture (4). Use four of the governor housing bolts to fasten governor housing (2) to fixture (4), but tighten the bolts with the fingers only.
(3) Loosen the two bolts (5) and install FT1525 Alignment Pin (6) through liner (7), and into both bores for the governor control shaft, in governor housing (2).
NOTE: The small diameter of alignment pin (6) fits in the inside bore for the control shaft, while the large diameter fits in the seal bore.
(4) When alignment pin (6) is all the way in liner (7) and fully engaged with both bores in governor housing (2), tighten bolts (5) and then tighten the four bolts that fasten governor housing (2) to the base of fixture (4). After all bolts are tight, be sure the alignment pin turns freely, then remove the alignment pin.
(5) Install drill bushing (8). Use a 1/2" electric drill with core drill (9) to make outer bore (A) to a larger size of 18.26Ø (.719"Ø).
(6) After outer bore (A) has been made to the larger size of 18.26Ø (.719"Ø), move the drill inward (forward) until the cutting end of core drill (9) comes into contact with the inner bore for the governor control shaft. Measure 12.7 (.50") from face (B) and put a mark at that specific location on the core drill. [In the illustration above, tape (C) has been put around the core drill to mark the 12.7 (.50") location.]
(7) Drill the inner bore for the governor control shaft to the depth of tape (C) [12.7 (.50") mark] that was put on core drill (9), in step 6 above. Remove core drill (9) and drill bushing (8).
(8) Install reamer bushing (10). Use reamer (11) with the electric drill to ream both the outer bore, and the inner bore for the governor control shaft to 18.82Ø ± .013 (.741"Ø ± .0005"). Use a mixture of one-half kerosene and one-half clean 30W motor oil for lubrication of reamer (11). Feed (push in) the reamer slowly and smoothly through outer bore (A) and then into the inner bore. The feed, speed and lubrication used during the reaming procedure will all have an effect on the finish size of the bore.
(9) After both the outer bore and the inner bore have been reamed to the correct size, remove governor housing (2) from the fixture; clean all metal chips from both bores, and especially clean fuel bypass drain hole (D) and its passage.
(10) See INSTALLATION OF 8N3945 BUSHING at the rear of this instruction for installation procedure.
Installation Of An Inner Bearing For The Governor Control Shaft (Governor Housings That Have An Outer Bearing)
The information that follows is for those early model governor housings that have been reconditioned once, and have a bearing installed in the outer bore for the governor control shaft, or, for later governor housings that are equipped new with a bearing in the outer bore for the governor control shaft.
(1) Remove seal (1) from housing (2). Remove gasket (3) and carefully file or sand the gasket face of housing (2) to remove any nicks or burrs. The gasket surface must be completely smooth and clean.
(2) Put FT1526 Fixture (4) in a vise as shown, and put governor housing (2) on fixture (4). Use four of the governor housing bolts to fasten governor housing (2) to fixture (4), but tighten the bolts with the fingers only.
(3) Loosen the two bolts (5) and install FT1525 Alignment Pin (6) through liner (7), and into both bores for the governor control shaft, in governor housing (2).
NOTE: The small diameter of alignment pin (6) fits in the inside bore for the control shaft, while the large diameter fits in the seal bore.
(4) When alignment pin (6) is all the way in liner (7) and fully engaged with both bores in governor housing (2), tighten bolts (5) and then tighten the four bolts that fasten governor housing (2) to the base of fixture (4). After all bolts are tight, be sure the alignment pin turns freely, then remove the alignment pin.
(5) Use an FT1698 Bearing Installation Tool to remove the bushing from outer bore (A).
(6) Install drill bushing (8). Put core drill (9) in a 1/2" electric drill. Move the drill inward (forward) until the cutting end of core drill (9) comes into contact with the inner bore for the governor control shaft. Measure 12.7 (.50") from face (B) and put a mark at that specific location on the core drill. [In the illustration above, tape (C) has been put around the core drill to mark the 12.7 (.50") location.]
(7) Drill the inner bore for the governor control shaft to 18.26Ø (.719"Ø), and to the depth of tape (C) [12.7 (.50") mark ] that was put on core drill (9) in step 6 above. Remove core drill (9) and drill bushing (8).
(8) Install reamer bushing (10). Use reamer (11) with the electric drill to ream the inner bore for the control shaft to 18.82Ø ± .013 (.741"Ø ± .0005"). Use a mixture of one-half kerosene and one-half clean 30W motor oil for lubrication of reamer (11). Feed (push in) the reamer slowly and smoothly into the inner bore. The feed, speed and lubrication used during the reaming procedure will all have an effect on the finish size of the bore.
(9) After the inner bore has been reamed to the correct size, remove governor housing (2) from the fixture and clean any metal chips from the bore, and especially clean fuel bypass drain hole (D) and its passage.
(10) See INSTALLATION OF 8N3945 BUSHING in this instruction.
Installation Of 8N3945 Bushing
(1) Put FT1698 Bearing Installation Tool (1) through outer bore (A) in the governor housing. Install an 8N3945 Bushing (2) on FT1698 Bearing Installation Tool (1). The chamfer on the outer diameter of the bushing (see inset on the illustration above) must be toward the inside of the inner bore as shown.
(2) Put a small amount of 9S3265 Retaining Compound on the outer diameter of the bushing, then install the bushing into the inner bore just far enough so face (E) of the bushing even with face (F) of the bore. This will give the maximum amount of contact on the end of the governor control shaft.
(3) Put 8N3945 Bushing (3) on FT1525 Alignment Pin (4) so the chamfer on the outside of the bushing (see inset on illustration above) is toward the inside of the governor housing. Put a small amount of 9S3265 Retaining Compound on the outer diameter of bushing (3).
(4) Install bushing (3) far enough in outer bore (A) so outer edge (G) is even with inside edge (H) of the seal counterbore as shown. If necessary, use the FT1698 Bearing Installation Tool to install the bushing to its correct depth. The bushing must be installed to the correct depth so it does not cause a restriction to the fuel bypass drain hole.
(5) Install the governor control shaft in the bore of the bushings as shown. Check to see if the control shaft turns smoothly in the bushing bores. If the shaft does not turn smoothly, but feels tight, there is a possibility that a bushing is installed slightly off-center (not straight). With this condition, make repairs as necessary to get correct operation of the governor control shaft, then assemble the governor.
(6) A 3208 governor housing, when originally assembled, has a thrust washer (5) and (6), at each end of governor control shaft (7). On some earlier model 3208 governor housings, the seal counterbore was machined deeper than it is on later model governor housings. When an 8N3945 Bushing is installed to the correct depth on the seal end of the control shaft on one of these earlier governor housings, the bushing will extend too far into the inside of the governor housing, and will not permit the installation of thrust washer (6) during assembly. If this condition exists, it is permissible to assemble the governor housing without a thrust washer (6).