Quincy QR-25 Series User manual

Information contained in this manual is presented as typical to all
QR-25 Series compressors. Photos, graphics and verbiage may or
may not be model specific. This manual contains important safety
information and should be carefully read and understood by all
personnel who service this product.
Manual No. 50255-101
September 2008 Edition
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Instruction Manual

QR-25 Teardown & Rebuild Quincy Compressor
50255-101, September 2008 1 3501 Wismann Lane, Quincy IL - 62305-3116
Contents
SECTION 1SECTION 1
SECTION 1SECTION 1
SECTION 1 SAFETYSAFETY
SAFETYSAFETY
SAFETY
Safety First ................................................................................................................................................... 2
SECTION 2SECTION 2
SECTION 2SECTION 2
SECTION 2 TEARDOWNTEARDOWN
TEARDOWNTEARDOWN
TEARDOWN
Preparation ................................................................................................................................................... 4
Removal of Basic Compressor ...................................................................................................................... 4
Removal of Unloaders and Heads ................................................................................................................ 5
Removal of Pistons, Rods and Rod Bearings ............................................................................................... 5
Removal of Oil Pump, Bearing Carrier and Crankshaft ............................................................................ 6
Removal of Rings, Bearings, Gaskets and O-rings ..................................................................................... 6
SECTION 3SECTION 3
SECTION 3SECTION 3
SECTION 3 CLEANING AND INSPECTIONCLEANING AND INSPECTION
CLEANING AND INSPECTIONCLEANING AND INSPECTION
CLEANING AND INSPECTION
Cleaning and Inspection ............................................................................................................................... 7
SECTION 4SECTION 4
SECTION 4SECTION 4
SECTION 4 REBUILDREBUILD
REBUILDREBUILD
REBUILD
Preparation ................................................................................................................................................... 8
Reassembly of Heads .................................................................................................................................... 9
Reassembly of Pistons and Rods ................................................................................................................ 10
Reassembly of Pistons and Rods into the Cylinder ................................................................................... 10
Reassembly of Crankshaft in Crankcase ................................................................................................... 10
Setting Crankshaft End Play ..................................................................................................................... 11
Reassembly of Oil Pump ............................................................................................................................ 11
Reassembly of Cylinder to Crankcase ....................................................................................................... 11
Reassembly of Head to Cylinder ................................................................................................................ 12
The Finishing Touches ............................................................................................................................... 12
Retorque Capscrews ................................................................................................................................... 13
Flywheel Run-out ....................................................................................................................................... 13
SECTION 5SECTION 5
SECTION 5SECTION 5
SECTION 5 SPECIFICASPECIFICA
SPECIFICASPECIFICA
SPECIFICATIONSTIONS
TIONSTIONS
TIONS
Standard and Oversize Cylinder Bore Dimensions ..................................................................................14
Crankshaft Throw Diameters .................................................................................................................... 16
Piston Ring Clearances (Single Stage Models).......................................................................................... 17
Piston Ring Clearances (Two Stage Models) ............................................................................................. 18
Clearances................................................................................................................................................... 19
Crankshaft End Play .................................................................................................................................. 20
SECTION 6SECTION 6
SECTION 6SECTION 6
SECTION 6 TOOLS AND PTOOLS AND P
TOOLS AND PTOOLS AND P
TOOLS AND PAINTAINT
AINTAINT
AINT
Tools ............................................................................................................................................................ 21
Paint ............................................................................................................................................................ 22

QR-25 Teardown & Rebuild Quincy Compressor
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SECTION 1SECTION 1
SECTION 1SECTION 1
SECTION 1 SAFETYSAFETY
SAFETYSAFETY
SAFETY
Safety First
At Quincy Compressor safety is not only a primary concern, but a faithfully
performed practice. Beginning with the design stage, safety is built into “The
World’s Finest Compressor”. It is the intention of this manual to pass along
the “safety first” concept to you by providing safety precautions throughout its
pages.
“DANGER !”, “WARNING !”, and “CAUTION !” are displayed in large
bold capital letters in the left hand column to call attention to areas of vital
concern. They represent different degrees of hazard seriousness, as stated
below. The safety precaution is spelled out in bold upper and lower case letters
in the right hand column.
Immediate hazards which will result in severe personal injury or death.
Hazards or unsafe practices that could result in personal injury or death.
Hazardsorunsafepracticeswhichcouldresultinminorpersonalinjury,product
or property damage.
Each section of this instruction manual, as well as any instructions
supplied by manufacturers of supporting equipment, should be read and
understood prior to performing teardown and rebuild procedures. If there are
any questions regarding any part of the instructions, please call your local
Quincy Compressor distributor, or the Quincy Compressor factory before
creating a potentially hazardous situation. Life, limb, or equipment could be
saved with a simple phone call.
Compressors are precision high speed mechanical equipment requiring
caution in operation to minimize hazard to property and personnel. There are
many obvious safety rules that must be observed during these procedures.
Listed below are some additional safety precautions that must be followed.
•Turn off and lockout/tagout (per OSHA regulation 1910.147) the main power
disconnect switch before attempting to work on or perform any maintenance.
•Do not attempt to service any part of the unit while it is operating.
•Allow ample time for the compressor to cool before performing service
procedures. Some surface temperatures exceed 350°F when the compressor is
operating.
•Per OSHA regulation 1910.147, relieve the system of all pressure before
attempting to service any part of the unit.
•Do not operate the unit with any of its safety guards, shields, or screens
removed.
•Do not remove or paint over any DANGER!, WARNING!, CAUTION!, or
WARNING !
CAUTION !
DANGER !

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instructional materials attached to the compressor. Lack of information
regarding hazardous conditions can cause property damage or personal
injury.
•Alterations must not be made to this compressor without Quincy Compressor’s
approval.
Do not operate a Quincy Compressor in excess of 250 PSIG unless it has been
testedandcertified for highpressure application by QuincyCompressor prior to
shipment.
•High pressure units (pressures exceeding 250 PSIG) require parts certified
for use in high pressure applications. When replacing parts on high pressure
units, please consult the parts manual and use only the part numbers listed
in that manual.
•Reckless behaviour of any kind involving compressed air is dangerous and
can cause very serious injury to the participants.
•Provisions should be made to have the instruction manual readily available
to the operator and maintenance personnel. If for any reason any part of the
manual becomes illegible or the manual is lost, have it replaced immediately.
The instruction manual should be read periodically to refresh one’s memory.
It may prevent a serious or fatal accident.
•Never use a flammable or toxic solvent for cleaning the air filter or any parts.
Air used for breathing or food processing must meet OSHA 29 CFR 1910.134 or
FDA 21 CFR 178.3570 regulations. Failure to do so may cause severe injury or
death.
The owner, lessor or operator of any compressor unit manufactured by
Quincy Compressor is hereby warned that failure to observe the safety
precautions and procedures outlined in this manual may result in serious
personal injury, damage to property, and may void your warranty. Quincy
Compressor must authorize all warranty service. Before contacting your
distributor or the factory, check the maintenance requirements and the
troubleshooting guide for your compressor. Most warranty issues can be
resolved by following proper maintenance procedures.
Quincy Compressor neither states as fact, nor in any way implies that the
above list of safety precautions is an all inclusive list, the observance of which
will prevent all damage to property or injury to personnel.
Every effort has been taken to ensure that complete and correct instruc-
tions have been included in this manual. However, possible product updates
and changes may have occurred since this printing. Quincy Compressor
reserves the right to change specifications without incurring any obligation
for equipment previously or subsequently sold.
WARNING !
WARNING !

QR-25 Teardown & Rebuild Quincy Compressor
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SECTION 2SECTION 2
SECTION 2SECTION 2
SECTION 2 TEARDOWNTEARDOWN
TEARDOWNTEARDOWN
TEARDOWN
Preparation
A clean, well lighted area with ample space to move about the compressor
must be available for the teardown and rebuild of a Quincy QR-25 series
compressor. Working in a confined area can lead to dangerous situations, so
allow yourself plenty of room. Mount the basic compressor on a rigid, sturdy
workbench before beginning the teardown and rebuild procedures.
Proper tools in good condition are also required and must be readily available.
Inspect all lifting hoists and straps prior to use. Always practice good
workshop habits and techniques when performing teardown and rebuild
procedures.
Removal of Basic Compressor
Perform Steps 1 through 10 prior to removing the basic compressor from the
unit.
Step 1. Turn off and lockout/tagout (per OSHA regulation 1910.147) the
main power disconnect switch.
Step 2. Allow ample time for the compressor to cool before attempting to
remove the basic compressor from the unit.
Step 3. Relieve all system air pressure from air tank(s). Also relieve air
pressure from interstage cooler (intercooler, if so equipped) by
pulling the ring on the pressure relief valve located on the head of
the compressor.
Neverattempttorelievesystempressurebydisconnectingfittings,pipes,tubing
or any other system components.
Do not rely upon a check valve to isolate a compressor from a pressurized tank
or compressed air delivery system during maintenance procedures.
Step 4. Remove the belt guard and belt(s) from the unit / basic compressor.
Step 5. Disconnect the discharge tube from the basic compressor and
remove the air filter.
Step 6. Loosen and remove the flywheel bolts. Use a wheel puller and
lifting strap to remove the flywheel from the crankshaft. It may be
necessary to wedge open the split in the flywheel to facilitate
removal.
Step 7. Remove the intercooler on two stage models and inspect.
Step 8. Remove the pressure relief valve, pilot valve and all control tubing.
WARNING !
WARNING !

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Step 9. Loosen compressor mounting bolts at the feet of the crankcase.
Carefully wrap a lifting strap around the basic compressor and
fasten the lifting strap to a suitable lifting device. Remove the
mounting bolts and lift the basic compressor off of the base or tank.
Step 10. Secure the basic compressor in an upright position on a sturdy
workbench. Drain all oil from the crankcase.
Removal of Unloaders and Heads
Step 1. Unscrew the six capscrews on top of the unloaders. Remove the
diaphragm cover plates, diaphragms and discs.
Step 2. Unscrew the unloader body with the appropriate unloader body
removal tool (refer to SECTION 6 - TOOLS AND PAINT -Tools).
This will expose the unloader piston assembly, holddown screw and
valve pin. The metal unloader body gaskets should also be removed.
Step 3. Remove the unloader piston assembly and valve pin. Remove the
holddown screw with appropriate holddown screw removal tool
(refer to SECTION 6 - TOOLS AND PAINT -Tools).
Step 4. Remove the screw and nut assemblies from the discharge valve
covers. Then remove all valve cover capscrews and valve covers.
Pull all valve components out of the head (note sequence of
components as they are removed).
Step 5. Carefully organize and segregate valve components on a clean
inspection surface in the order in which they were removed. Do not
mix components from one valve assembly with those from another.
Step 6. Loosen and remove the head bolts. Use a soft hammer to separate
the head from the cylinder. Place the head on a clean inspection
surface.
Removal of Pistons, Rods and Rod Bearings
Step 1. Inspect the top of the cylinder for abnormal wear, scoring or signs
of seizure.
Step 2. Remove the inspection plate from the side of the crankcase.
Step 3. Mate each connecting rod and cap by striking them lightly with a
metal punch and hammer. Connecting rods and caps must be
correctly matched during reassembly. Do not allow these
components to be reversed or interchanged at any time.

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Step 4. Remove the connecting rod nuts. Angle a long flat bar through the
inspection opening and under the threaded end tips of the rod bolts.
Rest the tip of the bar on the bottom of the crankcase and hold the
other end of the bar in one hand.
Step 5. Place a strap wrench over the end of the crankshaft and briskly
rotate the crankshaft downward. The rod bolts will loosen when
they strike the flat bar.
Do not remove piston assemblies through tops of cylinders. Ring grooves
occasionally form at the top of cylinder walls and can restrict removal of piston
assemblies. Remove cylinders from the crankcase prior to extracting the piston
assemblies from the bottom of the cylinder (see Steps 6 and 7 below).
Step 6. Remove cylinder-to-crankcase capscrews. Carefully lift cylinders
(with piston and rod assemblies still intact) from the crankcase.
Step 7. Pull the piston and rod assemblies through the lower end of the
cylinder. Mate and segregate all piston and rod assembly
components.
Step 8. Disassemble each piston rod assembly by removing a piston pin
retaining ring on one side of the piston and pushing the pin through
the piston from the other side.
Removal of Oil Pump, Bearing Carrier and Crankshaft
Step 1. Remove the oil filter (if so equipped). Loosen the capscrews and
remove the oil pump housing and pump components.
Step 2. Provide support for the crankshaft inside the crankcase. Loosen the
capscrews and remove the bearing carrier (and oil pickup assembly
if so equipped).
Step 3. Remove the bearing adjustment plate and shims.
Step 4. Carefully remove the crankshaft assembly (with bearings) from the
crankcase with a strap and lifting device.
Step 5. Also remove the oil pickup tube and screen from the crankcase (if
so equipped).
Removal of Rings, Bearings, Gaskets and O-Rings
All piston rings, rod bearings, crankshaft bearings and cups, gaskets and o-
rings must be removed and replaced. Adhere to strict workshop practices
when removing these components. A hydraulic press should be used to remove
crankshaft bearings and cups, and a ring expander should be used to remove
piston rings.
WARNING !

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SECTION 3SECTION 3
SECTION 3SECTION 3
SECTION 3 CLEANING AND INSPECTIONCLEANING AND INSPECTION
CLEANING AND INSPECTIONCLEANING AND INSPECTION
CLEANING AND INSPECTION
All salvageable components must be thoroughly cleaned with a non-flam-
mable solvent. Damaged and / or worn components must be replaced. Surfaces
that sandwich gaskets must be completely void of gasket residue. Piston ring
and o-ring grooves must be inspected for nicks or burrs and free of dirt and
grime. Threaded components must also be cleaned and inspected; all thread
sealant must be removed. Com-
ponents with damaged threads
must be replaced. Refer to the
appropriate parts book for genu-
ine Quincy Compressor parts
available from an authorized
Quincy distributor.

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SECTION 4SECTION 4
SECTION 4SECTION 4
SECTION 4 REBUILDREBUILD
REBUILDREBUILD
REBUILD
Preparation
Prior to starting the reassembly procedures, thoroughly clean the work area.
Clean all tools needed for the job and remove dirty rags. It is vital that the work
area be free from dirt, dust, grease and other foreign materials.
All compressor parts must be clean and within limits of specifications.
Machining and honing should be done prior to starting the reassembly
process. Honing is a critical operation and should be performed by trained
personnel with proper equipment. An improperly honed cylinder can result in
excessive oil consumption or loss of air delivery. Consult the factory for proper
honing specifications.
Typical Head Assembly

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Reassembly of Heads
Refer to the illustration on page 8 during reassembly of the heads. All gaskets
must be replaced with new gaskets and Quincy Compressor recommends
using new diaphragms in the unloader assemblies.
Step 1. Properly seat new valve gaskets in the valve pockets of the head.
Then install valve assemblies into each valve pocket.
Step 2. Insert valve pins and springs into the intake valve seats and place
a valve platform on top of the valve pins in each intake valve.
Step 3. Place spacers on top of all valve assemblies.
Step 4. Install new gaskets between the head surface and the valve cover
plates. Torque the capscrews per specifications (Refer to model
specific parts book for torque specifications).
Step 5. Thread a screw and nut assembly into each discharge valve cover
plate. Torque the capscrew per specifications and lock the nut
against the valve cover plate.
Step 6. Use the holddown screw tool (Refer to SECTION 6 - TOOLS AND
PAINT) to install a holddown screw into each intake valve cover
plate and torque to specifications.
Step 7. Insert a pin into each intake valve holddown screw. Place an
unloader piston assembly on top of each pin.
Step 8. Install a new gasket between the unloader body and the valve cover
plate. Torque the unloader body to specifications with an unloader
body tool (Refer to SECTION 6 - TOOLS
AND PAINT -Tools).
Step 9. Place a diaphragm disc over
each unloader piston assembly. Then
install diaphragm covers and capscrews
with new diaphragms on each unloader
body. Torque capscrews to specifications.

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Reassembly of Pistons and Rods
Step 1. Follow piston ring installation
instructions provided with the ring set.
Use a ring expander to properly install
the rings.
Step 2. Lightly oil the piston pins. In-
sert the piston pins through each piston
and rod. Secure the piston pins with
snap rings or setscrews.
Reassembly of Pistons and Rods into the Cylinder
Step 1. Stagger the piston ring gaps
on each piston and rod assembly.
Step 2. Use a ring compressor to care-
fully install each piston and rod assem-
bly into the appropriate cylinder bore
from the bottom side of the cylinder.
Step 3. Install new bearing inserts in
the rods and rod caps. .010 bearing in-
serts are available to fit crankshaft jour-
nals that have been reground. (Refer to model specific parts book
for replacement parts.)
Reassembly of Oil Pump
Step 1. Insert the driveshaft of the oil pump into the bearing carrier.
Step 2. Install the pump gerotor and the oil pump housing o-ring.
Step 3. Install the oil pump housing so that the arrow at the top of the
housing agrees with the proper rotation of the crankshaft.
Step 4. Install capscrews and torque to specifications.
Step 5. Turn the assembly over and carefully install the smaller o-ring on
the oil pump driveshaft.

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Reassembly of Crankshaft in Crankcase
Step 1. Place the crankshaft and bearings assembly in the crankcase.
Step 2. Align the holes of a new bearing carrier gasket with the oil passage
holes of the bearing carrier.
Step 3. Line up the slot of the oil pump driveshaft with the tongue in the
end of the cranshaft
Step 4. Support the crankshaft and re-install the bearing carrier / oil pump
assembly. Torque the capscrews per specifications.
Setting Crankshaft End-Play
Step 1. Firmly seat the crankshaft into the bearing carrier by rotating the
crankshaft and tapping it with a soft hammer.
Step 2. Place enough shims behind the
adjustment plate to allow zero end-play
and zero pre-load.
Step 3. Add shims so that when the
plate is torqued down, the specified end-
play exists (Refer to SECTION 5 -
SPECIFICATIONS - Crankshaft End
Play). End play should be measured
with a dial indicator.
Reassembly of Cylinder to Crankcase
Step 1. Lubricate each rod bearing surface.
Step 2. Lay a new crankcase-to-cylin-
der gasket on top of the crankcase.
Step 3. Insert two alignment studs in
threaded holes at opposite corners of the
crankcase.
Step 4. Carefully position the cylin-
der (pistons and rods included) over the
alignment studs.

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Step 5. Thread the cylinder capscrews
into the crankcase (remove alignment
studs after two opposing capscrews have
been started) but do not tighten.
Step 6. Place mated rod caps on the
rods and torque to specifications.
Step 7. Tighten and torque cylinder-
to-crankcase capscrews per specifica-
tions.
Reassembly of Head to Cylinder
Step 1. Lay a new head-to-cylinder
gasket on top of the cylinder.
Step 2. Use alignment pins to care-
fully position the head assembly on top
of the cylinder.
Step 3. Insert,
tighten and torque
head capscrews per
specifications in
proper torque sequence (see illustration).
The Finishing Touches
Step 1. Re-install the inspection plate(s) with new gasket(s). Torque
capscrews per specifications.
Step 2. Re-install the intercooler with new gaskets. Torque capscrews per
specifications.
Step 3. Re-install the flywheel and
torque capscrews to specifications.
Step 4. Install a new air filter element
in the air filter and re-install the air
filter on the basic compressor.
Step 5. Use a sufficient lifting device
to carefully place the rebuilt basic com-
pressor back onto the base or tank.
Step 6. Secure the basic compressor
to the base or tank with capscrews.
Step 7. Re-install the discharge pip-
ing, control piping, drive belt (refer to
drive belt installation and tension set-
ting instructions in the associated in-
struction manual) and belt guard.

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Step 8. Add clean lubricant to the crankcase per specifications (refer to QR-
25 Series Instruction Manual).
Step 9. Check for proper rotation of the flywheel by jogging the starter after
the basic compressor is completely installed.
Step 10. Immediately check for proper oil pressure at time of startup. Refer
to instructions and specifications in the QR-25 Series instruction
manual.
Insufficient oil pressure during operation of QR-25 Series compressors will
result in severe mechanical damage to the compressor.
Step 11. Check all control line fittings and discharge fittings for leaks by
applying a soapy solution to the fitting joints during operation.
Re-torque Capscrews
All capscrews and threaded fittings should be checked for tightness after 100
hours of operation.
Turn off and lockout/tagout (per OSHA regulation 1910.147) the main power
disconnect switch before performing maintenance procedures.
Flywheel Run-out
Radial flywheel run-out can be measured with a dial indicator positioned
adjacent to the belt groove of the flywheel (see illustration). The maximum
allowable run-out is .018”.
Do not attempt to measure the run-out within the belt groove; measurements
taken from within the belt groove will be inaccurate.
WARNING !
CAUTION !
CAUTION !

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SECTION 5SECTION 5
SECTION 5SECTION 5
SECTION 5 SPECIFICATIONSSPECIFICATIONS
SPECIFICATIONSSPECIFICATIONS
SPECIFICATIONS
Standard & Oversize Cylinder Bore Dimensions
Standard and oversize pistons and rings are available for many QR-25 series
compressors. Refer to the individual parts books for specific part numbers.
Prior to reassembly, cylinders must be honed. If oversize pistons and rings are
to be used, the cylinder must be bored and honed to the correct and precise
dimensions listed in this manual. All measurements, boring and honing
procedures must be performed by a qualified technician.
Each piston must be measured for nominal dimensions. Cast iron pistons
must be measured at various diameters around the piston below the ring
grooves. Aluminum pistons must be measured across the bottom of the piston
skirt parallel to the piston pin bore.
Piston to cylinder clearance must be measured with each piston in the
appropriate cylinder. Use a feeler gauge to measure the clearance as shown
in the illustration at left. Measure around the diameter as well to determine
tight spots.
Fig. 5-1
Piston to Cylinder Clearance
Insert feeler gauge between
piston and cylinder wall.
Model Cylinder
Part No. Standard .010 Oversize Model Cylinder Part No. Standard .010 Oversize
X2 2101 2.0005
2.0000 2.0105 2.0100 212 1912 2.5005 2.5000 2.5105 2.5100
X3 7465 2.3755
2.3750 2.3855 2.3850 214 7708 2.7505 2.7500 2.7605 2.7600
X8 2108 2.3755
2.3750 2.3855 2.3850 215 7708 2.7505 2.7500 2.7605 2.7600
A4 1767 2.5005
2.5000 2.5105 2.5100 216 1913 3.001 3.000 3.0105 3.0100
106 1915 2.5005
2.5000 2.5105 2.5100 230 7888 3.5005 3.5000 3.5105 3.5100
108 1916 3.0005
3.0000 3.0105 3.0100 240 7889 4.001 4.000 4.0105 4.0100
206 6569 2.0005
2.0000 2.0105 2.0100 244 6653 4.0005 4.0000 4.0105 4.0100
207 6569 2.0005
2.0000 2.0105 2.0100 270 7281-2 4.500 4.501 4.510 4.511
208 6525 2.2505
2.2500 2.2605 2.2600 255 5825 4.5005 4.5000 4.5105
4.5100
210 6533 2.5005
2.5000 2.5105 2.5100 4088 6653 4.0005 4.0000 4.0105 4.0100
211 6533 2.5005
2.5000 2.5105 2.5100 4110 5825 4.5005 4.5000 4.5105 4.5100
4125 7281-2 4.500
4.501 4.510 4.511

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Model Cylinder
Part No. Standard .010 Oversize Model Cylinder Part No. Standard .010 Oversize
R-15 Vac
R-17 Vac 1768 4.0005 4.0000 4.0105 4.0100 4088 Vac 6653 4.0005 4.0000 4.0105 4.0100
230 Vac 7888 3.5005
3.5000 3.5105 3.5100 4110 Vac 5825-1 4.504
4.503 4.514 4.513
240 Vac 7889 4.0005
4.0000 4.0105 4.0100 4125 Vac 7281-1 4.504
4.503 4.514 4.513
244 Vac 6653 4.0005
4.0000 4.0105 4.0100 W264 Vac 1332 4.5005 4.5000 4.5105 4.5100
255 Vac 5825-1 4.504
4.503 4.514 4.513 W280 Vac 1333 5.0005 5.0000 5.0105 5.0100
270 Vac 7281-1 4.504
4.503 4.514 4.513
Model Cylinder
Part No. Standard .010
Oversize Model Cylinder
Part No. Standard .010
Oversize
W264 1332 4.5005
4.5000 4.5105 4.5100
390 (L.P.)
390 (H.P.) 2333
7.501
7.500
4.0005
4.0000
7.511
7.510
4.0105
4.0100
W280 1333 5.0005
5.0000 5.0105 5.0100
5080 (L.P.)
5080 (H.P.) 6654
5.2515
5.2500
3.0005
3.0000
5.2615
5.2600
3.0105
3.0100
306 (L.P.)
306 (H.P.) 7173
2.7505
2.7500
2.0005
2.0000
2.7605
2.7600
2.0105
2.0100
5105 (L.P.)
5105 (H.P.) 7395
6.0015
6.0000
3.2505
3.2500
6.0115
6.0100
3.2605
3.2600
308 (L.P)
308 (H.P.) 1908
3.0005
3.0000
1.7505
1.7500
3.0105
3.0100
1.7605
1.7600
5120 (L.P.)
5120 (H.P.) 7396
6.0015
6.0000
3.2505
3.2500
6.0115
6.0100
3.2605
3.2600
310 (L.P.)
310 (H.P.) 1909
3.5005
3.5000
2.0005
2.0000
3.5105
3.5100
2.0105
2.0100
W340 (L.P.)
W340 (H.P.) 7029
5.2515
5.2500
3.001
3.000
5.2615
5.2600
3.011
3.010
325 (L.P.)
325 (H.P.) 6610
4.503
4.502
2.5005
2.5000
4.513
4.512
2.5105
2.5100
W350 (L.P.)
W350 (H.P.) 7030
6.0015
6.0000
3.2505
3.2500
6.0115
6.0100
3.2605
3.2600
340 (L.P.)
340 (H.P.) 6654
5.2515
5.2500
3.0005
3.0000
5.2615
5.2600
3.0105
3.0100
W5080
(L.P.)
W5080
(H.P.)
7029
5.215
5.2500
3.001
3.000
5.2615
5.2600
3.011
3.010
350 (L.P.)
350 (H.P.) 7395
6.0015
6.0000
3.2505
3.2500
6.0115
6.0100
3.2605
3.2600
W5105
(L.P.)
W5105
(H.P)
7030
6.0015
6.0000
3.2505
3.2500
6.0115
6.0100
3.2605
3.2600
370 (L.P.)
370 (H.P.) 8262
6.0015
6.0000
3.2505
3.2500
6.0115
6.0100
3.2605
3.2600
W5120
(L.P.)
W5120
(H.P.)
7280
6.0015
6.0000
3.2505
3.2500
6.0115
6.0100
3.2605
3.2600
Standard & Oversize Cylinder Bore Dimensions (cont.)

QR-25 Teardown & Rebuild Quincy Compressor
50255-101, September 2008 16 3501 Wismann Lane, Quincy IL - 62305-3116
Crankshaft Throw Diameters
Model(s) Crankshaft
Part No.
Throw Dia.
(inches) Model(s) Crankshaft
Part No.
Throw Dia.
(inches)
X2, X3 6975
.9363
.9358
270 111238-002
2.2485
2.2480
X8 6974
.9363
.9358
244, 255,
340
110518
2.2480
2.2485
A-4,
106, 108,
R-15, R-17
1523 1.7505
1.7500 350 110220-001 2.2485 2.2480
206, 208,
210, 214,
306
110777 1.2500
1.2495 370 111238-001 2.2486 2.2481
212, 216,
308, 310
110218
1.7505
1.7500
390 112521
2.2485
2.2480
230, 240,
325
110216
1.7505
1.7500
5080, 5105,
5120
110226-001
2.2485
2.2480

QR-25 Teardown & Rebuild Quincy Compressor
50255-101, September 2008 17 3501 Wismann Lane, Quincy IL - 62305-3116
Piston Ring Clearances
Single Stage Models
Models Top 2nd 3rd 4th 5th Oil
X2 .005
.015 .005 .015 .004 .012
X3 .005
.020 .005 .020 .005 .015 .030 .156
X8 .005
.015 .005 .015 .005 .015 .030 .156
A4 .005
.017 .005 .017 .005 .017 .010 .055
106 .005
.013 .005 .013 .005 .017 .010 .055
108 .005
.015 .005 .015 .005 .015 .015 .055
206 .005
.015 .005 .015 .005 .015 .004 .012
208 .005
.013 .005 .013 .005 .013
210 .005
.017 .005 .017 .010 .055
212 .005
.017 .005 .017 .005 .017 .010 .055
214 .005
.015 .005 .015 .005 .015
216 .005
.015 .005 .015 .005 .015 .015 .055
230 .005
.025 .005 .025 .005 .020 .015 .055
240 .005
.020 .005 .020 .005 .020 .015 .055
244 .005
.023 .005 .023 .005 .020 .015 .055
255 .005
.015 .005 .015 .005 .015
4088 .005
.023 .005 .023 .005 .020 .015 .055
4110 .005
.015 .005 .015 .005 .015
4125 .005
.015 .005 .015 .008 .019 .015 .055
R-15, R-17 .005
.023 .005 .023 .005 .023 .005 .023 .005 .023
230VAC .005
.025 .005 .025 .005 .025 .005 .025 .005 .025
240VAC .005
.023 .005 .023 .005 .023 .005 .023 .005 .023
244VAC .005
.023 .005 .023 .005 .023 .005 .023 .005
.023
Low Pressure Piston Rings

QR-25 Teardown & Rebuild Quincy Compressor
50255-101, September 2008 18 3501 Wismann Lane, Quincy IL - 62305-3116
Piston Ring Clearances
Two Stage Models
Models Top 2nd 3rd 4th 5th Oil Top 2nd 3rd 4th 5th Oil
306 .005
.015 .005 .015 .005 .015 .005 .013 .005 .013 .004 .012
308 .010
.020 .010 .020 .005 .015 .015 .055 .004 .012 .004 .012 .004 .012 .004 .012
310 .005
.020 .005 .020 .005 .020 .015 .055 .005 .015 .005 .015 .005 .015 .004 .012
325 .005
.015 .005 .015 .008 .019 .015 .055 .005 .017 .005 .017 .005 .017 .010 .055
340 .013
.023 .013 .023 .013 .023 .010 .027 .005 .015 .005 .015 .005 .015 .015 .055
350 .010
.025 .010 .025 .015 .027 .025 .065 .005 .015 .005 .015 .005 .020 .010 .050
370 .010
.025 .010 .025 .015 .027 .025 .065 .005 .015 .005 .015 .005 .020 .010 .050
390 .008
.028 .008 .028 .018 .033 .015 .033 .005 .020 .005 .020 .005 .020 .005 .020 .015 .055 .005 .020
5080 .007
.027 .007 .027 .013 .023 .010 .027 .005 .015 Obs. Obs. .005
.017
5105 .010
.025 .010 .025 .010 .027 .025 .065 .005 .015 .005 .020 .005 .020 Obs.
5120 .010
.025 .010 .025 .015 .027 .025 .065 .005 .015 .005 .015 .005 .020 .010 .050
Low Pressure Piston Rings High Pressure Piston Rings