Geely JL481Q, Manual

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For example, cylinder block No.“2” + crankshaft No. “1” = total number “3”, i.e., use No. 3 bearing shell.
For standard bearing shell sizes, see Table 1.
(3) Detaching crankshaft
Take out crankshaft with lifting action: remove the main bearing shell and upper thrust washer from the cylinder block.
(4) Checking the radial run out of crankshaft
Place the crankshaft on the V-type block. Use micrometer to measure the radial jumping (Fig. 55) in the middle of journal.
Max. radial run out: 0.03mm.
If the radial run out is larger than the maximum value, replace the crankshaft.
(5) Checking main bearing journal and connecting rod bearing journal.
a. Measure the diameters of each main bearing journal and connecting rod bearing journal (Fig. 56);
If the diameters are not up to the standard, check the oil clearance. When necessary, grind or
replace the crankshaft.
b. Check the taper and degree of roundness of each main journal and connecting rod bearing journal;
Max. taper and degree of roundness: 0.02mm.
If the taper and degree of roundness is larger than the maximum value, replace the crankshaft.
II. Assembly
1. Installing Crankshaft
(1) Install the main bearing
a. Align the protrude portion of main bearing (upper harf) with the recess on the cylinder block
bearing seat while pushing 5 upper bearing shell through (Fig. 57, 58);
b. Align the protrude portion of lower bearing shell with the recess on the main bearing cap
while having 5 lower bearing shell pushed through (Fig. 59).
(2) Install thrust washer (Fig. 60)
Place two crankshaft thrust washers under the No. 3 journal of air cylinder block with oil groove facing outside.
(3) Put the crankshaft onto the cylinder block.
(4) Install Main bearing cap and thrust washer
a. Place 2 crankshaft thrust washers onto No. 3 main bearing cap to make the oil groove face
outside (Fig. 61);
b. Place 5 main bearing caps on the proper position (Pay attention to the front mark), (Fig.62);
c. Apply a thin layer of engine oil under the head of the main bearing bolts and at the thread;
tighten evenly 10 bolts diagonally from the middle to both ends.Torque:
(MR479Q,MR479QA)60N.m.(MR481QA)70Nm.(JL481Q)80Nm.
Finally, check the crankshaft radial clearance.
Table 7
1 2 3
1
4
2
5
0
3
2
4
1
3
0
2
2
3
1
2
0
1
Dimension Grouping
Cylinder
block
Crank-
shaft
Bore Diameter of
bearing seat
Diameter of Main
bearing journal
Bearing shell required
Grouping of Crankshaft Joumal & Bearing Shell Dimensions
81