yanmer 3JH2 Series Reassembly of fuel injection pump
Preparation：
After inspection, put all parts in order and clean.
See Inspection of Fuei Pump for inspection procedure.
(1) Put in the plunger barrel from the top of pump.
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NOTE: Make sure the barrel key groove is fitted properly to the barrel stop pin.
(2) Place the delivery valve assembly, packing, spring and stopper from the top of the pump, in that order.
NOTE: Replace the delivery valve packing and O-ring.
(3) Place the control rack, and tighten the control rack stop bolt.
NOTE: 1. Do not forget the rack aux. spring.
2. Make sure the rack moves smoothly through a full cycle.
(4) Piace the rack set screw (using the special tool) in the rack stop bolt screw hole to fix the rack.
(5) Looking from the bottom of pump, align the match marks on the rack and pinion.
Control ck Pincti
(6) While holding the pinion with one hand and keeping it aligned with the match mark, fit in the sleeve, and light-
ly tighten the small pinion screw.
NOTE: Fitting of sleeve; Face towards small pinion screws and align with match mark.
Pinion/sleeve match mark Match mark
(7) Mount the plunger spring upper rest.
NOTE: 1. Be sure to mount the upper rest with the hollow side facing down.
2. Recheck to make sure that the rack moves easily.
(8) Mount the plunger spring.
(9) Mount the lower rest on the head of the plunger, and fit the plunger in the lower part of pump while align-
ing the match marks on the plunger flange and the sleeve.
(10) Insert the plunger spring support plate between the plunger spring seat B (lower) and fuel pump, by put-
ting the handle of a hammer in the lower part of pump and pushing the roller guide up.
NOTE: 1. Face the roller guide stop groove upwards, and align it with the stop screw hole on the pump.
2. Check the movement of the rack. The plunger spring may be out of place if the movement is heavy -insert a screwdriver and bring it to the correct position.
3. When replacing the roller guide assembly, tit shims and lightly tighten: Standard shim thickness
1.2 mm (0.0472 in.)
Part code number
129155-51600
(11) Make sure that the roller guide stop groove is in the correct position, and tighten the roller guide stop bolt.
(12) Fit the bearings to both ends of the camshaft, and in sert from the drive side by tapping lightly.
NOTE: Turn the pump upside down, and tap in the cam-
shaft while moving the roller guide to the plunger spring side.
(13) Fit the oil seal on the inside of the bearing retainer and mount the bearing retainer.
NOTE: Coat the camshaft and oil seal with oil to prevent the oil seal from being scratched.
(14) Fix the pump, lightly tap both ends of the cam shaft with a wooden hammer, and adjust the cam shaft side clearance with the adjustment shims while checking with a side clearance gauge.
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(15) Mount the fuel pump side cover.
(16) Tap in the camshaft wood ruff key.
(17) Turn the camshaft, and pull out the plunger spring support plate.
NOTE: Fit double nuts to turn the camshaft.
(18) Tighten the delivery valve retainer.
NOTE: 1. Tighten the retainer as far as possible by hand-
if the bolt gets hard to turn part way, the packing or delivery vaive are out of place. Remove, cor-
rect, and start tightening again.
2. Overtightening can result in malfunctioning of the rack.
(19) Fit the delivery retainer stop and tighten the stop bolt.
(20) Mount the fuel feed pump
NOTE: Refer to the instructions for reassembly of the fuel feed pump.
