4.5. Bent shaft and flywheel

Fig. 2.5. Details of the block of cylinders and krivoshipno-conrod mechanism of GA14DE and GA16DE engines: I \with the mechanical transmission; II \with the automatic transmission; 1 — the block of cylinders; 2 — the holder of a back cuff of a bent shaft; 3 — a drain stopper of cooling liquid of the block of cylinders; 4 — an arm; 5 — inserts of radical bearings of a bent shaft; 6 — persistent half rings of a bent shaft; 7 — a bent shaft; 8 — covers of radical bearings of a bent shaft; 9 — the plug of the drive of the oil pump; 10 — an asterisk of a bent shaft; 11 — segment splines; 12 — a cover of the lower head of a rod; 13 — connecting rods; 14 — a rod; 15 — lock rings; 16 — a piston finger; 17 — the piston; 18 — an oil scraper ring; 19 — the lower compression ring; 20 — the top compression ring; 21 — a back cuff of a bent shaft; 22 — a back cover; 23 — a flywheel; 24 — the lower cover; 25 — a back cover; 26 — the conducted disk

Bent shaft pig-iron, five-basic with four counterbalances (see fig. 2.5 and 2.6).

Fig. 2.6. Details of the block of cylinders and krivoshipno-conrod mechanism of the SR20DE engine: 1 — a gas distribution mechanism drive chain cover; 2 — an arm of fastening of the generator; 3 — the water pump; 4 — the block of cylinders; 5 — the holder of a back cuff of a bent shaft; 6 — persistent half rings; 7 — a flywheel; 8 — a back cover; 9 — a bent shaft; 10 — an insert of the radical bearing; 11 — a cover of the radical bearing; 12 — a bed of radical bearings of a bent shaft; 13, 14 — the maslootrazhatelny screen; 15 — an aluminum case; 16 — a maslouspokoitelny guard; 17 — a steel stamped case; 18 — a stopper of a drain opening; 19 — a cover; 20 — a rod and a cover of a rod; 21 — inserts of the lower head of a rod; 22 — lock rings; 23 — a piston finger; 24 — the plug of the top head of a rod; 25 — the piston; 26 — piston rings; 27 — an oil receiver with the filter of the oil pump; 28 — a sealing ring

On diameter of radical and conrod necks bent shafts are broken into three dimensional groups, except for a bent shaft of the SR20DE engine having four dimensional groups (tab. 2.3).

Engine model	Dimensional group
	1	2	3	4
Diameter of radical necks
GA14DE and GA16DE engines	49,956-49,964	49,948-49,956	49,940-49,948	-
SR20DE engine	54,974-54,980	54,968-54,974	54,962-54,968	54,956-54,962
Diameter of conrod necks
GA14DE and GA16DE engines	39,968-39,974	39,962-39,968	39,956-39,962	-
SR20DE engine	47,968-47,974	47,962-47,968	47,956-47,962	-
Gap between an insert and a radical neck
GA14DE and GA16DE engines	0,018-0,042 (nominal)
SR20DE engine	0,004-0,022 (nominal)
GA14DE and GA16DE engines	0,1 (maximum)
Gap between an insert and a conrod neck
GA14DE and GA16DE engines	0,010-0,035 (nominal)
SR20DE engine	0,020-0,045 (nominal)
GA14DE and GAS16DE engines	0,1 (maximum)
Axial gap of a bent shaft
GA14DE and GAS16DE engines	0,06-0,18 (nominal)
SR20DE engine	0,10-0,26 (nominal)
All engines	0,3 (maximum)
Axial gap of a rod
All engines	0,20-0,47 (nominal)
	0,52 (maximum)
Ovality of radical and conrod necks, no more
All engines	0,005
Conicity of radical and conrod necks, no more
All engines	0,002

Two persistent half rings are established in nests on both sides from the central support of a bent shaft. They provide adjustment of an axial gap of a bent shaft. Half rings are established by the party with flutes to a bent shaft.

The pig-iron flywheel is fixed by bolts on cranked to a shaft. Centering of a flywheel is provided with the adjusting plug. The maximum axial beating of a flywheel on diameter of 115 mm should not exceed 0,15 mm.

Fig. 2.8. Marking of dimensional groups of diameters of cylinders on the block of GF14DE and GA16DE engines: 1 — numbers of dimensional groups of diameters of cylinders; 2 — numbers of dimensional groups (categories of the sizes) of inserts of bearings of a bent shaft; 3 — number of dimensional group of diameter of the cylinder No. 1; 4 — number of dimensional group (category of the size) of inserts of the bearing No. 1

Fig. 2.11. Marking of dimensional groups of diameters of necks of a bent shaft: 1 — a code of dimensional groups of diameters of conrod necks of a bent shaft; 2 — a code of dimensional groups of diameters of radical necks of a bent shaft; 3 — a tag of dimensional group of diameter of a conrod neck No. 1; 4 — a tag of dimensional group of diameter of a radical neck No. 1

Fig. 2.12. Inserts of radical bearings of a bent shaft: 1 — the insert with a flute and an opening for lubricant, is established from the block of cylinders; 2 — the smooth insert, is established in a cover of the case of the radical bearing; 3 — marking by paint of dimensional group

The marking facilitating their complete set is applied on the block of cylinders and a bent shaft. Marking includes a five-digit code of category of the sizes of the established inserts and diameters of cylinders. In fig. 2.8 and 2.11 examples of interpretation of the specified parameters are given. Inserts of radical bearings thin-walled steel with a working surface from aluminum-tin alloy. The inserts installed in the block of cylinders have flutes and openings for lubricant. The inserts established in covers of bearings, smooth (fig. 2.12). On thickness all inserts are broken into dimensional groups which are marked by paint at an end face.

Inserts of conrod bearings also steel thin-walled with a working surface from aluminum-tin alloy. Inserts from a rod have an opening which at assembly is combined with an opening in a rod body. Connecting rods are broken into the groups on thickness marked by paint at an end face (tab. 2.4) too. Repair inserts also differ on dimensional groups.

Engine	Dimensional group and color
	0 black	1 brown	2 green	3 yellow	4 blue	5 pink	6 white
Radical inserts
GA14DE MGA16DE	1,827-1,831	1,831-1,835	1,835-1,839	1,839-1,843	1,843-1,847	-	-
SR20DE	1,977-1,980	1,980-1,983	1,983-1,986	1,986-1,989	1,989-1,992	1,992-1,995	1,995-1,998
Connecting rods
GA14DE MGA16DE	1,503-1,506 *	1,506-1,509	1,509-1,512	-	-	-	-
SR120DE	1,500-1,503 *	1,503-1,506 **	-	-	-	-	-

Thickness of inserts of GA14DE and GA16DE engines, mm:

radical:

       +0,25 1,960—1,964

       +0,50 2,085—2,089

conrod:

       +0,08 1,542—1,546

       +0,12 1,562—1,566

       +0,25 1,627—1,631

Thickness of inserts of the SR20DE engine:

radical:

       +0,05 2,109—2,117

conrod:

       +0,08 1,541—1,549

       +0,12 1,561—1,569

       +0,25 1,626—1,634