Instructions for using YN27C gasoline rock drill machine Shandike

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Detailed instructions on the technical specifications, operating methods, maintenance, troubleshooting, and other aspects of YN 27 and YN 27C internal combustion rock drills. The document first introduces the basic structure and working principle of the rock drill, and then elaborates in detail on the preparation work before operation, start-up, rock drilling, tool replacement, parking, impact operation, and operating precautions. In addition, specific steps and troubleshooting methods for maintenance, inspection, and adjustment work are provided.

1.Weight of main machine:	27kg
2.0verall   dimensions:	746×315×229mm
3.Type   ofengine:	single  cylinder,air  cooled  two  strokes
4.Cylinder  Diameter  X  stroke  ofpiston:	58×70mm
5.Rotating  speed  of engine:	≥2450r/min
6.Displacement  of  engine  piston:	185cm³
7.Type  of carburetor:	hand  needle  valve,no  floating  type
8.Ignition   system:	ontrollable    silicon,contactless    system
9.Drlling   speed:(mean  value  offive  holes)	≥250mm/min
(After  holing,drill  φ34,with  drill  rod  of  600mm in  length,is  drilled  vertically  downward  into  medium  hard granite(f=8-12)to  make  five  holes  in  succession.The  mean  value  of  the  five  holes  are  counted  as  the  speed.)
10.Max  drilling  depth:	6m
11.Fuel   consumption:	≤0.12L/m
12.Tank   capacity:	≥1.14L
13.Mixture ratio of gasoline and lubricating oil(in volumes):	12:1
14.End of dill rod dimensions:	22×108mm
15.Rotating  speed of drill rod:	≥200r/min
16.Clearance  of spark plug:	0.5-0.7mm

Fig.No.	Qty	Description
1	1	Hammer piston
2	1	Piston ring set
2A	1	Piston ring
2B	1	Piston ring
3	1	Piston ring
4	1	O-ring
5	1	Hammer piston guide
6	1	Ratchet housing
7	1	Ratchet wheel assy
8	6	Spring
9	6	Roller
10	1	Spacer
11	1	Lock ring
12	1	Rotating sleeve
13		Collet assy
14	1	Gasket
15	1	Drill chuck assy
16	1	Operating shaft
17	1	Locking nut
18	1	Screw
19	1	Lever
20	1	Pin
21	1	O-ring
22	1	0-ring
23	1	Spring housing
24	1	O-ring
25	1	Spring
26	1	Plunger
27	1	Yoke spring
28	1	Lock pin
29	1	Yoke bolt assy
30	1	Spring
31	2	O-ring
32	1	Drill yoke
33	1	Drill yoke nut

Fig.No.	Qty	Description
1	1	Hammer piston
2	1	Piston ring set
2A	1	Piston ring
2B	1	Piston ring
3	1	Piston ring
4	1	O-ring
5	1	Hammer piston guide
6	1	Drill chuckassy
7	1	Yoke spring
8	1	Lock pin
9	1	Rotating sleeve
10	1	Drill yoke
11	1	Yoke bolt assy
12	1	Spring
13	2	O-ring
14	1	Drill yoke nut
15	1	Lock ring

Fig.No.	Qty	Description
1	1	Cylinder
2	2	Stud bolt
3	1	Gasket
4	1	Exhaust pipe
5	6	Nut
6	1	Washer
7	1	Clip
8	10	Screw
9	1	Blow valve seat
10	1	Gasket
11	2	Spring
12	2	Valve washer
13	1	Tube
14	1	Rubber hose
15	2	Lock ring
16	1	Intake valve seat
17	2	Bushing
18	1	Suction duct
19	2	Screw
20	1	Spark plug
21	1	Cleaning needle
22		Inlet valve
23	1	Shield
24	1	Handle assy
25	1	Side handle
26	2	Bolt
27	1	Bushing
28	1	Label
29	1	Gasket

Fig.No.	Qty	Description
1	1	Crank case assy
2	3	Stud
3	4	Stud
4	1	Stud
5	4	Stud
6	4	Stud
7	1	Retainer ring
8	3	Rubber cushior
9	1	Spacer
10	1	Needle bearing
11	7	Nut
12	19	Nut
13	10	Stud bolt
14	2	Draw bolt
15	2	Spring washer
16	2	Nut
17	1	Cap nut
18	1	Flywheel and Magneto classis parts
19	1	Gasket
20	1	Crankcase cover
21	1	Pin
22	1	Bushing
23	1	Needle bearing
24	1	Spacer
25	1	Retainer ring
26	1	Crank shaft assy
27	1	Needle bearing
28	1	Key
29	1	Engine piston set
30	1	Gudgeon pin
31	2	L ock ring
32	2	Piston ring
33	1	Piston ring
35	1	Plate
36	1	Wearing plate

Fig.No.	Qty	Description
1	1	Magneto chassis
2	1	Gasket
3	1	Electronic unit
4	1	Induction coil set
5	1	Bushing
6	4	Bolt
7	1	Cable terminal
8	1	Spark plug
9	1	Flywheel assy
10	1	Lock ring
11	1	Nut
12	1	Ignition cable

Fig.No.	Qty	Description
1	1	Clutch body
2	4	Ball
3	1	Snap ring
4	1	Stop screw
5	1	Rubber plug
6	1	Starter pulley
7	1	Needle bearing
8	1	Starter rope set
9	1	Starter handle
10	1	Rope bracket
11	1	Starter covei
12	1	Gasket
13	1	Starter spring
14	1	Fuel tank assy
15		Fuel tube
16	1	Fuel filter
17	1	Tank cap
20	1	O-ring
21	1	Fuel tank cover
22	1	Guide rope piles
23	15	Stud
24	2	Pin
25	1	Stud bolt
26	6	Nut

Fig.No.	Qty	Description
1	1	Control
2	1	Pin
3	4	Screw
4	1	Nut
5	1	Wing nut
6	1	Spring
7	1	Retainer cup
8	1	0-ring
9	1	Fuel needle assy
10	1	Fuel valve seat
11	1	O-ring
12	1	Nozzle,lower
13	1	Adjusting screw
14	1	Nut
15	1	Throttle set
16	1	Nut
17	1	Spring washer
18	1	Throttle control
19	1	Spring
20	1	Spring seat
21	1	Retaining ring
22	1	Throttle seat
23	2	O-ring
25	2	Leaf valve
26	2	Support
27	4	Spring washer
28	1	Stud
29	1	Lock clip
30	2	Valve sheet
31	2	Handle sleeve
32	1	Handle assy
33	1	Filter housing
34	2	O-ring
35b	1	Filter element
36	1	Gasket

YN27C rock drill machine CONSTRUCTION

1.Engine:The engine is a hand operated single cylinder and two stroke petrol engine with air cooling,reflux air conversion,no contact ignition,and no floating-type carburetor.It is composed of control parts,starter parts,oil tank parts,flywheel parts,crankshaft,connecting rod,crankshaft case parts,shield parts,magneto parts,piston parts and cylinder parts.
2.Air compressor:The engine piston and hammer piston are mounted separately in the upper and lower place of the cylinder.These two pistons move up and down synchronously.The hammer piston and the bigger bore of the cylinder form a compression chamber,Which together with air inlet and outlet valves and ventilator valves,form the air compressor.It is composed of hammer piston parts and cylinder parts.
3.Rock drill:It is composed of hammer piston parts,rotation mechanism parts and drill chuck parts.

Lubrication and Cooling Action 

Fuel used by the drill is 12:1,that is ,a mixed oil in the proportion 12 parts of gasoline to 1 part of lubricating oil.In operation,mixed oil enters into the crankshaft in fog to lubricate all parts of the crankshaft and the cylinder.During burning,gasoline burns,most of lubricating oil flow into all touching parts through the cylinder space to make them get complete lubrication.
The cylinder of engine is cooled by wind from the flywheel through the surface of emitting heat plates.

YN27·YN27C Operation

(1)Preparation  before  starting:

Preparing  with   mixed   oil,drill   rod,bit,funnel   with  filter   net,some   service   tools   and spark plug,etc.The ratio of mixed oil is  12:1.When the temperature is high or the quality of the lubricating oil is different,it can be adjusted to 6:1 to 10:1 as appropriate.

1.Gasoline:Use gasoline of 93#or 95#.

2.Lubricating   oil:Use   two-stroke   gasoline engine    lubricating oil or automotive lubricant,or  low-condensation  lubricant  at  lower  temperature.

3.Length  of  dill   rods  and  diameter  of  the  carbide   percussive  drillbit:When  drilling,a group  of  drill  rod  length  with  different  size  should  be  prepared  in  order  to  operate

conveniently and safely.They are 0.6m,1.1m,1.6m,2.0m,2.6m,3.0m,selecting them according to the depth of hole.In operating,o.6 is used to drill at first,then  1.1m  instead of smaller one(Fig.1),then they are easy to choose and can work normally.

1、Erect the  machine to  support the  handle  of the  control  body  ,and  fill  fuel  into the gasoline    tank.(Fig.2)

2.Close the air filter.(Fig.3)
3.Rotate the wing nut of fuel valve in counter clockwise one cycle or two to open it.(Fig.4)

4.Pull the starter wire rope slowly for several times to let the mixed oil into the cylinder.When combustible gas in the cylinder burns,stop pulling.(Fig.5)

5.0pen the air filter.(Fig.6)
6.Pull the starter wire rope rapidly and powerfully to start.(Fig.7)After that the machine runs idly for several minutes in order to heat it,then turn the wing nut of fuel valve clockwise ,its rotating speed rises gradually.If abnormal sound with fog in the exhaust pipe,that means fuel supply is not enough.Right now,please turn the wing nut of the fuel valve in a counter clockwise direction and increase the amount of fuel supply.

7.Attention   points   for   starting:

Mixed oil entering into the cylinder being too much or insufficient will be adverse to the starting of the engine.The operator is asked to make a correct judgement for the amount of the mixed oil in the cylinder.The method is to observe the state if a jet of fuel emerges from the exhaust pipe.If poor,please make the wing nut of fuel valve rotate in counter clockwise direction,open fuel valve full.Pull wire rope until combustible gas enter the cylinder burns and the engine be started.If a jet offuel emerges from the exhaust pipe,that means the fuel supply is too much,please make the wing nut of fuel valve rotate in clockwise direction and pull the starter wirerope for several times until it is operating then adjust the wing nut of the fuel valve in a appropriate position.(Fig.8)

(3)Drilling

1.Fitting rod:Press the throttle valve with thumb to make the machine operate with lower speed ,then insert the shortest drills rod into the rotating sleeve.Snap down the yoke so that  bit will  notjump  out.(Fig.9)

2.Start to drilling:Select an appropriate position.Slow down the rotating speed of the machine,use a foot to guide bit for facilitating the make hole.

3.Drilling hole:Release the throttle valve ,let the machine run at full speed.During operation,add appropriate pressure so that no jumping occurs to the machine.If the rotating speed of the machine is too low,adjust the fuel valve to raise its speed.

(4)Changing of rod

(4)Changing of rod Changing of rod ,press the throttle valve to reduce its rotating speed Snap up the yoke by foot,take out the bit and replace another one.Snap down the yoke and then accelerate the machine to full speed.

(5)Stopping:

Stop to work for short time,only press the throttle valve ,or close the air filter.Stop to work a long time,the fuel valve should be closed.(Fig.10)to avoid the too much oil enters into the cylinder.

(6)Hammering:

If digging,breaking,splitting or ramming:

1.To  YN27 dismantle the rotating  sleeve  and  mount  the  notch  of the hammer sleeve alingning with the round  pin  in the  drill  chuck  cover,and  dismante  the  vetilating  pipe  between  the  cylinder  and  the  drill chuck cover assy,then all hammering operations are able to be carried out.

2.To YN-27C you can operate  in(Fig  .12a)manner.

(7)Attention points for operation:

1.Fuel  filling:only  after  the  machine  is  stopped.

2.If  the  machine misfires,make  an  inspection.Don’t  pull  the  starter  wire  rope  vigorously  to  avoid damage to the Parts.

3.During  operation  ,don’t  press  the  machine  by  human  body  to  avoid  to  valid  accidents  when  a  bit breaks

4.When a  bit  is  blocked  ,don’t  move  it  directly  with  the  machine.

5.At  the  initial use  of  a   new  machine  ,the  throttle  valve   is  not  to   be  regulated   high.Only  after  the machine is well mastered  ,its speed can be regulated higher.

6.Working   in   terribly   hot   area,be   cautious   that   the   operation   period   is   not   too   long.When   the temperature of the  machine  is too  high,a  short stop  is  necessary till  it  gets cool.

7.To  avoid  corrosion,the  machine  should  be  stored  at  dry  places.

Maintenance,Inspection and Adjustment

(1)To  observe  strictly  the  maintenance  of  the  machine  tool  can  not  only  ensure  reliable  running  of machine,but  also  prolong  its  service  life.

1.Before  filling  into  oil  tank,mixed  oil  must  be  filtered.

2.After  starting,the   machine  tool  should   beatitude  without  any   loads  for  2-3   minutes  to   lubricate  all sides in order to reduce trouble and prolong its life.

3.Everyday,operating  4  hour,take  out  the  filter  and  wash  itin  gasoline.

4.Every week,outer of the machine and entitling heat plate of cylinder should be cleaned to send out heat.

Diagram of Air filter

5.When  the   machine  is  running,the  deposited  carbon  is  easily  formed in  the   gas  duet  and  on  the   other  parts.Especially  the   bevel  gas  duct  in cylinder  must  be  assured of its free flow.When  cleaning the  bevel  gas duct, switch  down  the  inlet  valve,take  out  cleaning  needle  and  wipe  out  the deposited carbon in the bevel gas duct by the needle.(Fig.12)The inlet valve should also be kept lean.Several holes in the valves should be ensured free

 passage to allow free motion of the steel ball.

6.When  running  of  the machine  is  abnormal  make  an  overall  inspection of  engine  or  make  carbon  cleaning  ,to  wipe  out  carbon  accumulated  piston  ring  ,engine piston  and  impact piston  ,exhaust  hole  in  cylinder  wall  and  spark  gap.Dirt  on  the  flywheel  and  magneto  should  also  be  taken away.

(2)Attention points for Inspection:

1.Be  sure  that  clearance   between  spark  gap  electrodes  should   be  0.5-0.7mm  and  constantly  clean  off carbon and dirties to avoid circuit break and reduction of ignition.(Fig.11)

2.Be sure that the clearance between the steel ball of inlet valve and round pin. 3.Be sure that seal of the check valve plate at the bottom of control body.

4.Be  careful  whether  the  angle  of  ignition  is  changed.The  arrow  of  flywheel  should  be  aligned  with  the sign  on  the  crankshaft.

Disassembling and assembling 

The    machine    must    be    assembled    correctly,strictly    sealed    and perfect    cleanness.After    a period  of  service,the   machine   needs   cleaning   and   repairing,so   disassembling   and   assembling   are of  a  common  occurrence.The  following  cautions  should  be  followed  in  disassembling  and  assume bluing:

1.Disassembling and assembling should be done according to procedure.The parts,especially the piston tings,are to be mounted on their original positions.No errors and missing are allowed.

2.All  the   parts  need  to   be  washed   in   kerosene  or  gasoline   and  applied  a  layer  of   lubrication oil.In   assembling,drive   tight   all   the   screws    nuts    and    spark    plug.Before    trial    running,pull   the starter  wire   rope  slightly  for  several  times,to   see   if  it  is  rotating  freely,then   start  the   machine.

3.If   the   machine    need   an   overall    disassemble   it   according   to   the   following    procedure.For assembling,do    it    reversibly:

In  partial  repair,do  not  disassemble  the  parts,which  need  no  repairing.Try  by  every  means  to disassemble  only  the   parts  wanting  to   be  repaired.

4.In   disassembling    starter    parts,take   off    the    starter   spring,Starter    wire    pulley   and    starter cover  together,be  careful  that  spring   breaks.The   connection   between   clutch   and   crankshaft   is   left threaded,disassemble  it  in  clockwise.And  the  starter  wire  rope  should  be  mount  in  the  wire  pulley slot  according  to  the  arrow  on  starter  cover.

5.In assembling  the  torque  mechanism  parts,be  sure  that  the  straight  and  drift  slots  on  the impact  piston  lever  are  correctly  in  mesh  with   impact piston  lever  are  correctly  in  mesh  with   inner keys  of  upper  rachet  and   rotating  sleeve.

6.Be very careful in disassembling piston ring to avoid  breaking.

7.In  disassembling the engine piston,a notch on the  piston should be faced to the hole of spark plug.

8.Connecting crankshaft case.Cylinder and drill chuck cover.Two long screw levers should be driven tight in interchangeably to ensure the uniform pulling force,but not too tight.

Trouble shooting

Fault	Cause	Remedy
1.The engine is  difficult to star	1.Fuel system:(1).Clogging or poor sealing of fuel passages(2).Clogging of gasoline filter.(3).Use  of  a  wrong  brand  of gasoline,over flow fuel or water in the fuel.(4).Poor sealing of the check valve plate on the control body.(5).Overflow mixed fuel in cylinder  2 Flectric system(1).Irregular gap between the spark plug electrodes,and oil conation,accumulated carbon on its surfaceorloose fitting of the plug core.(2).Shifting of the flywheel from its normal position(Wrong angle forignition)   3.Pneumatic system:(1).Low ratio of compression:a.Carbon deposition in or wear the cylinder.Engine positon ring.b.Clogging of the bevel gas duct in cylinderc.Irregular clearance of the steel ball in the inlet valve.(2).Air in sufficient supply:Carbon deposition in the outlet on  cylinder and the connection pipe of the Silencer.	Take out of needle valve,blow thefuel hole of oil tank and block it witha hand,then shave it to make astream of oil sprays from the hole. Disassemble it,inspect and clean it  Choose or blend the fuel by theregulations.Disassemble it and adjust it.Close fuels door,disassemble inletValve,pull starter wire rope for several times,take away overflow  fuel.  Adjust the gap by the regulationclear away carbon or oil or replace the plug with a new oneAlign the arrow on flywheel with the sign on the crankshaft.       Clean or replace it.Clean away carbon in time. Adjust the steel ball clearance between 0.5-0.7mm Clean itin time.

Fault	Cause	Remedy
2.The engine worksinefficiently.	1.Unfitting fuel door or clogging of fuel passage.2.Carbon deposition in the bevel  gas duct,inlet valve,outlet valve and piston ring. 1.Clogging in the center hole of	Adjust it. Clean it in time.   Clean it
3.Poor removal of cuttings	drillrod.2.Damage of hexagonal seal ring. 3.Damage or clogging of inlet and outlet valve.4.1rregular size and shape of tool shank.	Replace itReplace them. Replace it.
4 Poor rotation of tool shank.	1.Damage of upper ratchet or olive ring.2.Excessive wears of keys of impact piston rod,Upper ratchet,Rotatingsleeve and other relevant parts.3.Running inefficient of engine.	Replace Replace See the	it. them.  above.
	1.Seizer of the impact piston and	Eliminating the case and make
5.The engine races.	drill rod.2.Changing of the flywheel sing.	rotation sleeve run freely. Adjust it and align it with the sign of crankshaft.
6.Abrupt stop of the machine	1.Clogging of the hole in oil tankcap.2.Wrong with electric of fuel system3.Carbon deposition in the machine or excessive temperature	Clean it. See the above.Give it a complete overhaul.