Motor Refurbishment¶

Electrical Pre-Check¶

Connect the drive cable connector from the motor windings tester to the motor. Then connect the cable on the tester to the top plug and place the selector to A/OL. Connect the multimeter to the motor windings tester.

Set the multimeter to the Ohm setting.

Resistance A to Ground = O.L. A-B, A-C, A-D = 242-260 and ± 2 ohms between each leg.

PINS	A	B	C	gnd
A	NA	242-260	242-260	OL
B	242-260	NA	242-260	OL
C	242-260	242-260	NA	OL
gnd	OL	OL	OL	NA

Rotor Check¶

Check if Rotor is True¶

Install the crank to the front plate gauge and power the motor observing the gauge movement.

installed crank gauge — Positioning of the dial indicator fixture.

Be sure that the indicator arm is clear of the crank pin.

arm clear of pin — Indicator arm clear of the pin.

Once positioned correctly lock the dial indicator into place.

dial indicator lock — Mounting fixture in locked position.

If the crank is not straight (the indicator needle is swaying) proceed to Straightening The Rotor. If straight, proceed to Remove Used Motor Crank.

Straighten Rotor¶

When the gauge indicates the crank is orientated to the high spot use the mallet to tap downward on the crank.

The crank is at a high spot when gauge needle sways to a HIGHER number.

swaying crank gauge — The indicator is showing the high spot on the cranks rotation.

The indicator is showing the low spot on the cranks rotation.

mallet strike — Strike downward on the crank when it is at its highest spot.

Rotate the crank and check for swaying on the gauge. If there is still swaying then repeat the Straightening The Rotor process until there is no more swaying.

Remove used motor crank¶

Warning

Only use non ball-end hex keys. Ball-end hex keys increase the risk of stripping the hex socket.

Warning

Apply light pressure to avoid stripping out the hex socket. L

Warning

Loctite may be present and a heat gun will be required before the screw can be removed with light pressure.

Remove the motor set screw with a 2.5mm hex L-key.

hex L key in the set screw — Hex L key inserted into the set screw.

Warning

The 3 jaw puller may be required to remove the crank in order to not damage the shaft of the rotor.

Pull the crank off by hand or use the 3 jaw puller if needed.

three jaw puller on the crank — Three jaw puller needed to remove a difficult crank.

Remove Power Receptacle¶

Remove Cover Screws¶

Remove the 4 x JIS # 2 screws from motor receptacle exposing the terminal connectors and ground wire.

vessel screw driver — JIS #2 screwdriver needed for the receptacle screws.

remove cover screws — Removal of the cover screws

Receptacle cover lifted — Exposed ground wire and terminal connections.

Disconnect Ground Wire¶

Remove the 1 x JIS # 2 screw from ground wire ring terminal.

Place all the screws in the repair bin.

Disconnect Power to Terminals¶

Disconnect the triangular connector from the terminals from motor back plate and place it in the repair bin.

terminal connector — Triangular Connector

Torque Test¶

Aeroquip Removal¶

Remove the used aeroquip from the back plate using 1 ⅛” socket and recycle used aeroquip.

1-1/8" socket — 1-1/8 inch deep well socket used for removing the aeroquip.

aeroquip removal — Removal of the aeroquip with the impact driver.

Warning

Never take a metal pick to the cold head sealing surfaces. If you must use a tool it must be a non-marring pick of wood or plastic stylus.

Remove the used -018 o-ring and discard it.

removing -018 o-ring — Remove the aeroquip o-ring using a wooden pick or plastic stylus.

Fastening to the Torque Tester¶

Zero the scale using the adjustment at the top of the scale.

adjustment knob — Scale adjusted to - 0 Kgs -

Select the crank shaft coupling labeled RDK2 and place it onto the shaft of the clutch.

installing the crank shaft adapter to the clutch — Install the crank shaft adapter to the clutch of the torque tester.

Line up the keystock on the motor shaft to match the keyway on the clutch coupling.

keystock lined up with the clutch. — The keyway of the adapter is aligned with the keystock on the motor shaft.

Align the alignment screw labeled RDK with the mounting hole in the motors aluminum front plate.

Note

In order to get the actuating lever to seat the motor must be oriented with the flat mounting surface on the back plate facing upwards.

etched RDK label — Aligned screw with the mounting hole.

Use the red lever to push the motor flush to the torque tester.

red lever actuated holding the motor flush and tight — Red lever tight.

secured motor — The motor is secured in the torque tester.

flush motor front plate with the torque tester. — The motor front plate is seated flush against the plate of the torque tester.

Operating the Torque Tester¶

Powering the Motor¶

Connect the power receptacle to the motor back plate and energize.

Motor back plate receptacle connected — The torque tester receptacle connected to the back plate

Energize the motor — The motor powered in the torque tester.

Energizing the clutch¶

Power on the torque testers power supply.

power button on the power supply. — Location of the power button.

Slowly increase the course voltage by rotating the knob clockwise.

Note

The course voltage knob is very sensitive and requires very slow movement.

Recording Torque¶

Increase the voltage carefully observing the needles location on the internal scale labeled kilograms.

The needle rising on the scale and the voltage increasing on the power supply display. — The needle on the scale will react to the force placed on the clutch.

Once the motor begins to slip, take not of the highest stable location the needle arrived to prior to slipping.

stable needle around 6.30kilograms — Torque tester stable at 6.3 Kgs.

Highest torque before slipping — The highest torque before the needle begins to shake.

image of the scale needle while the motor is slipping.

The motor torque has a pass fail threshold of 6.00kgs.

Conversion Scale

Kilograms	in/oz
0.1 kgs	10 in/oz
0.5 kgs	50 in/oz
1.0 kgs	100 in/oz
2.0 kgs	200 in.oz
3.0 kgs	300 in/oz
4.0 kgs	400 in/oz
5.0 kgs	500 in/oz
6.0 kgs	600 in/oz

Recording Vibration¶

Vibration is recorded subjectively.

Vibration Terms.

Term	Fail	Pass	Ask
Smooth		X
Low VBR			X
Med BVR	X
High BVR	X
Grinding	X
Croaking	X

Removing the Motor from the Torque Tester¶

Return the course voltage back to 0v by rotating the knob counter clockwise and power off the clutch power supply.

Remove the power cable from the receptacle and disconnect the receptacle from the motor.

Disengage the red handled actuator and slid the motor out of the clutch coupling.

Motor Crank Processing¶

Motor Shaft Reconditioning¶

Warning

Do not use a file. Doing so will create flat edges.

Note

Be sure to orientate the keystock to the top of the shaft.

Remove the keystock with side cutters. Grip the keystock with the jaws of the side cutters as low as possible on the front of the motor shaft.

side cutters gripping the keystock — Grip the end of the keystock against the motor shaft.

Like a lever pry upwards with the side cutters to lift the keystock out of the keyway.

Re-fit the crank onto the shaft and rotate it by hand. Be sure that the crank is slip fit and that there is no binging during rotation.

motor shaft with the keystock removed. — Keystock Removed.

crank slip fitted over the shaft. — Slip fit the crank over the shaft with the keystock removed.

Smooth out the shaft of the rotor using the 320 grit emory cloth strips. Using a buffing motion, work all the way around the motor shaft so that all the surfaces are clear of debris and burrs.

Buffing the rotor shaft with emory cloth. — 320 Grit emory cloth buffing the motor shaft.

Hone the interior of the crank body with a wire brush to clear out any debris that could cause gumming.

honing the inside of the crank body. — Crank Hone

Re-fit crank by hand and rotate to ensure slip fit. The shaft and crank body may need to be processed multiple times until it is smooth.

Replacing the Crank Pin¶

Pin Removal¶

Warning

Use safety glasses when operating the hydraulic press.

Using the hydraulic H frame press, center the crank pin under the ram of the press.

center the crank under the Hydraulic press — Crank centered under the hydraulic press.

Press out the pin and recycle it.

pressing out the pin — Press the pin out.

Pin Installation¶

Select replacement crank pin with least amount of knurling (.317) and test fit by hand.

.317 pin test fitting — Fitting the .317" pin. Here it is too loose

Test each size until the knurling does not fit into the pin hole. This allows for a snug pressing so the pin doesn't fall out under normal operation.

test fit .325 — The .325 pin knurling does not fit into the crank. This is a good size selection.

The back side of the crank is indicated by the location of the set screw. The set screw is closest to the back side of the crank.

The set screw on the back side of the crank. — The set screw is closer to the back side of the crank.

Insert the finished side of the pin through the back side side of crank. The pin should stop when the knurling reaches the crank pin hole. If the pin falls through go to the next size up.

finished side of the pin through the back side of the crank. — Pin inserted into the rear of the crank with the knurling at the back end.

Press crank pin in using the arbor press. The pin should go in with medium pressure.

Testing the Pin Tension¶

Test the pin fit tension by forcefully tapping crank pin side down on Rubber coated bench top.

demonstrated grip of the crank for tapping — Grip the crank firmly.

tapping on the bench — Tap the pin repeatedly to see if it begins to back out of the crank.

If the pin moves, remove it using the arbor press and use the chisel to peen an X shape on 2-3 locations of the knurling.

Danger

Wear eye protection when using striking tools to prevent a potential eye injury. The striking tool or hammer may chip or break causing projectile metal.

Cradle the pin in the crevice on the vice anvil.

Holding the chisel to the knurling — Cradle the pin.

3 sets of X's on the — Repeat the process and make three X's around the pins knurling.

Repeat the Testing the Pin Tension instructions until the pins stays tight during the tap test.

Place complete crank in repair bin for later installation.

Disassembling the Motor¶

This stage of the procedure involves the complete disassembly of the motor components.

End Plate & Bearing Removal¶

Crank Plate Removal¶

Remove 8 x M6 motor bolts with 5mm hex key on impact driver in a star pattern and place the fasteners in the repair bin.

motor with the numbered star pattern. — Remove the bolts by number.

Place the motor in the front-plate removal fixture with rotor facing towards you.

motor in plate removal fixture — Motor placed in the fixture with the back flush against the wood.

motor fastened into the fixture — The motor fastened down in the fixture.

Using the large 2 jaw puller, begin removing crank plate.

2 jaw puller on the crank plate. — The two jaw puller needs to be turned slightly cattywampus in order to grip the front plate.

Check to see that the stator is not being pulled along with the crank plate.

Note

You should be able to see a gap forming in between the motor stator and the aluminum front plate.

gap forming at the stator and crank plate. — Gap forming at the stater and crank plate.

If the stator is coming along with the crank plate, tap the crank plate with mallet until a gap forms.

Note

If the stator is stuck to the crank plate, you will notice separation forming at the back plate.

Tap with rubber mallet — Tap the crank plate with the mallet unit it comes loose.

Place the crank plate in the "to be verified" bin.

Crank Bearing Removal¶

Using small 2 jaw puller with the impact driver, remove crank side bearing and recycle it.

puller with impact gun on bearing. — Bearing puller.

Back Plate Removal¶

Remove the motor from the fixture to access the back plate. Using the rubber mallet, tap the lip of the back plate alternating sides with each strike.

Note

The electrical connections are short and can be damaged if the back plate tugs on the wires. Once the back plate is free from the stator, slowly rotate the plate to expose the connections.

Tapping back plate with the mallet — Alternate sides with each strike.

After the back plate comes loose rotate the plate to expose the spade connections.

Rotate the back plate to expose the electrical connections.

Use a metal hooked pic to slide the spade connectors from the straight terminals.

pulling the spade connectors off with the pic. — Pull the spade connectors off with the metal pick.

Back Plate Bearing Removal¶

Using small 2 jaw puller with the impact driver, remove back side bearing and recycle it.

2 jaw pullers with impact gun on back plate bearing.

Warning

Over crimping the connectors will damage the connector. Be sure to press lightly.

Using the retaining clip tool, squeeze the electrical connectors on stator to make sure that they will seat the next time they are connected to the terminals.

retaining ring plier squeezing the spade connectors. — Press the spade connector slightly to restore tension in the connector.

Cleaning The Motor¶

Cleaning the Rotor¶

Clean rotor faces with kim wipes and alcohol.

Tip

Knock the accumulated clumps of dust off with a dry kim wipe into the garbage before applying the alcohol to the face of the rotor.

dry clumps of dust being wiped off with the kim wipe.

Cleaning the Stator¶

Blow air gently between the roto and the stator.

Warning

Damaging the insulation on the windings will cause an electrical short. Be careful not to come into contact with the windings with anything.

blowing air between the stator and the rotor.

Blow air through stator holes.

New Bearing installation¶

Crank Bearing¶

Obtain 2 x 6202-2Z bearings

Place a bearing over the shaft of the rotor and slide the bearing mandrel over the shaft of the rotor.

crank bearing mandrel — Mandrel used to press the bearing onto the shaft.

bearing on the shaft of the rotor with the mandrel. — The mandrel should fit over the shaft to press on the inner ring of the bearing.

Place the motor in the arbor press with the mandrel side down.

motor in the press. — Balance the motor with your hands.

Press down on the back side of the rotor to drive the crank side bearing onto the rotor shaft.

ram head pressing on the back of the rotor.

Back-Plate Bearing¶

In order to press the back-plate bearing onto the rotor you must reinstall the crank bearing mandrel to support the rotor.

Center the bearing on the back of the rotor, align the back-plate bearing mandrel over the bearing and press it into position using the arbor press.

Clean O-ring Surfaces¶

Place the motor in the PVC cleaning fixture with the crank side down.

Warning

This process involves bringing tools close to the motor windings. Coming into contact with the windings will damage them and the motor. Scratching the varnish off will cause permanent damage.

Using a kim wipe with alcohol on a wooden pick, clean the o-ring surface of any loose dirt or residual grease.

Using the scotch brite on the wooden pick, sand the o-ring surface.

Use compressed air, blow the sealing surface to clear any dust or debris.

Using a kim wipe with alcohol and wooden pick, clean the o-ring surface again.

Note

Flip over the motor and repeat the cleaning steps so that both sides fo the motor are cleaned.

Preparing end plates¶

Obtain a new Motor crank plate and refurbished motor back plate.

Clean any dirty surfaces and hole with a brushes.

Using a tube cleaning tool on the impact driver, polish the relief valve.

--

Clean the o-ring gland with brush, pipe cleaner, then kim wipe.

Blow off the alcohol from the end plates with compressed air until they are dry.

Assembling the Motor¶

O-ring Installation¶

Obtain 2 x -044 o-rings.

Apply an even thin coat of vacuum grease onto the o-ring and then install it into the o-ring grooves.

Note

Applying too much vacuum grease can cause leaks and damage to the o-ring from cutting.

Pinch and release o-ring radially to ensure that they are not twisted.

The pinching motion lifts the o-ring out of the groove and allows the oring to untwist from rolling the o-ring into position. Do this in 2 - 3 locations around the motor.

End plates installation¶

Install 3 x spring washers into back plate bearing housing.

spring washers installed into the back plate.

Connect the electrical wires onto the connectors in clockwise order - Black, White, Red. Take note of the length of each wire and their order.

The red should be the longest wire and installed on the furthest terminal.

Once they are all connected, push the back-plate onto the stator by hand until the o-ring is seated.

Place the motor crank shaft toward you with the flat portion of the back plate down on the bench. Install crank plate with the gas holes with three to the left and right.

front plate installed with gas hole orientation.

Squeeze the crank plate with your hands until the o-ring is seated.

Using a star pattern, lightly tighten the 8 x M6 motor bolts with impact driver.

star pattern orientation of the motor fasteners.

Ensure the crank plate and back plate flat section are true. Tap with a mallet to settle the plates.

Use the torque wrench in a star pattern to tighten the motor bolts.

Star pattern photo with the pattern numbered.

Be sure the torque wrench is set to (VALUE IN INCH POUNDS).

Test the motor rotor has smooth rotation by turning the crank by hand.

Warning

Keep clear of the receptacle pins during this process. The turning action will produce voltage and shock you.

Drive Receptacle Installation¶

To install the motor drive connector fasten 1 x JIS # 2 screw on connector ground wire ring terminal.

Install triangular connector by hand.

Fasten the receptacle down with 4 x JIS # 2 screws on the housing.

Quality Check the rebuild¶

Begin by verifying the electrical connections of the motor. To do this repeat the steps in the Electrical Pre-Check.

Resistance A to Ground = O.L. A-B, A-C, A-D = 242-260 and ± 2 ohms between each leg.

PINS	A	B	C	gnd
A	NA	242-260	242-260	OL
B	242-260	NA	242-260	OL
C	242-260	242-260	NA	OL
gnd	OL	OL	OL	NA

Perform the Torque Test steps and record the results.

1. Vibration = Low, Med, High

2. Torque >= 600 oz in

Obtain a new -018 o-ring, apply small amount of grease and install it on the aeroquip bung.

--

Obtain a new aeroquip and green heat shrink.

Install the aeroquip using the 1 ⅛” deep well socket and the impact driver.

Use the heat gun to shrink the green tubing on the back of the aeroquip.

Crank Installation¶

Install the new keystock into the keyway with the watchmakers hammer.

Warning

The shaft must be supported by the support fixture during the tapping process or the shaft will bend.

Striking the keystock with the wm hammer.

Use the calibrated (FIVE OR SIX MILLIMETER SPACER) to install the crank the proper distance from the front-plate.

Slide the crank onto the shaft.

Make sure there is no gap between the crank an the spacer but don't press so hard the spacer cannot be removed.

Tighten the set screw with 2.5mm L-key

Complete the motor repair form.

Place the motor in the ready-to-use area.

Appendix¶

For motors that do not spin freely and or have low torque after repair…
Remove end plates.
Check Bearing housing I.D. to be less than or equal to .0005”
Check -44 o-ring groove base to be 102.16-102.20 mm.
Check bearings for ease of spinning, replace as necessary.
Reassemble and retest.
If still not free spinning remove rotor and inspect for lamination's separation or debris between rotor and stator.
Remove debris or replace rotor or stator depending on source of interference.
Re-assemble motor as per directions above and set for Re-Mag.
For motors that are shorted or have bad windings…
Remove rotor, inspect lamination.
If lamination's separated, record tag and set aside for future repair.
Place tag with electrical information on stator and bag for future re-winding.
Obtain stator with good Ohms and re-use (if in good condition) rotor or obtain good rotor from stock.
Re-assemble motor as per directions above and set for Re-Mag.