Can't remove crank arm

You will need to remove the shrouds on wither side of the Exercise bike. You will see on each crank, or at least one of them, there is a cotter pin with a bolt The cotter pin needs removing and you will be able to turn that pedal arm to 180' to the other one. Spare parts appear to be obsolete, but you should get parts for the crank arm from a good cycle shop. Very often the cotter pin needs to be filed to fit. Tightening the nut locks it in place. There are two videos, the second one refers to cycles which is where my experience comes from.

https://www.manualslib.com/manual/2258999/Diamondback-910ic.html#manual

Pedals are NOT pressed on to crank arms.
The PEDAL is *screwed* onto the CRANK ARM (left pedal - reverse thread). The CRANK ARM is *pressed* onto the square, tapered CRANK SPINDLE with a bolt or nut. To remove a crank arm that is tightly mounted to the spindle requires a crank arm extractor, which a bike shop would have, or which can be purchased online.

I’m happy to help further over the phone at https://www.6ya.com/expert/donald_f2ed37026a3ac881

You need a tool like this
Bike Bicycle Cycle Crank Extractor Remover Puller

see this causes and fix it. God bless you
Lubrication

Detach the ends of the pedals from the crank axles. Spread a layer of machine grease over the crank axles, then reattach the ends of the pedals.
2

Remove the bolts connecting the pedals to the swing arms. Detach the pedals from the arms, then spread a layer of machine grease over the axles on the swing arms. On some models, the bolts may also serve as the axles. Reattach the pedals to the arms.
3

Remove the bolts connecting the swing arms to the elliptical's upright. Detach the swing arms from the upright, then spread a layer of machine grease over the axles on the upright. Reattach the arms to the upright.
1 Drive Belt

Remove the screws or bolts securing the ends of the pedals to the crank axles. Slide the ends of the pedals off the axles. Remove any screws or bolts securing the left and right disc shields to the base unit. Pull or pry the disc shields off the base unit and set them aside.
2

Remove any screws or bolts securing the left and right side shields to the base unit. Detach the side shields and set them aside. Examine the interior of the base unit and locate the drive belt.
3

Pull the drive belt free of the crank pulley, flywheel and any other pulleys. Discard the old drive belt and install a new belt in its place. Turn the crank axles by hand to confirm that the belt will turn smoothly when the device is in use.

Hi there:
Isnt a diagram but If you have removed the motor, here is the motor installation procedure....

INSTALLATION PROCEDURE



Align the wiper motor to the wiper drive system module. NOTE: Refer to Fastener Notice in Service Precautions.
Install the wiper drive system module to wiper motor screws. Tighten Tighten the wiper drive system module to wiper motor screws to 7 N.m (62 lb in) .
Connect the electrical connector to the wiper motor.
Install the crank arm on the wiper motor.




Rotate the washer solvent container into the installation position.
Install the washer solvent container screws. Tighten Tighten the washer solvent container screws to 6 N.m (53 lb in) .
Inspect the wipers for proper operation.




Also, here is the crank arm procedure...

REMOVAL PROCEDURE

Remove the wiper system module cover.
Remove the drive link from the wiper motor crank arm.

2.1. Loosen the drive link screws.
2.2. Remove the drive link from the wiper motor crank arm.

Remove the wiper motor crank arm cover and seal.
Remove the wiper motor crank arm from the wiper motor.

4.1. Loosen the wiper motor crank arm screw.
4.2. Tap on the wiper motor crank arm screw with a soft-faced mallet while holding up on the wiper motor crank arm until the wiper motor crank arm loosens from the wiper motor.
4.3. Remove the wiper motor crank arm screw and the wiper motor crank arm from the wiper motor.

INSTALLATION PROCEDURE




Install the wiper motor crank arm onto the wiper motor.

1.1. Turn the ignition switch to the ACCY position.
1.2. Set the wiper switch to PULSE position. The wiper motor should be operating.
1.3. Turn the ignition switch to OFF when the wiper motor is in the innerwipe position.

IMPORTANT: Do not rotate the wiper motor shaft during the installation of the wiper motor crank arm.

1.4. Install the wiper motor crank arm on the wiper motor while maintaining a 4-8 mm (0.157-0.315 in) gap between the V-grove in the wiper motor crank arm and the tab.

NOTE: Refer to Fastener Notice in Service Precautions.

Install the wiper motor crank arm screw. Tighten Tighten the wiper motor crank arm screw to 16 N.m (12 lb ft) .
Install the wiper motor crank arm cover and seal.




Check the gap between the wiper motor crank arm and tab. If the gap is not 4-8 mm (0.157-0.315 in) , remove the wiper motor crank arm and repeat installation steps.
Install the drive link onto the wiper motor crank arm.
Install the drive link screws. Tighten Tighten the drive link screws to 5 N.m (44 lb in) .
Install the wiper system module cover.
Inspect the wipers for proper operation.

Additional procedures: Wiper Motor Module Replacement.

TOOLS REQUIRED
J 39822 Wiper Arm Puller

REMOVAL PROCEDURE

Turn the ignition switch to the ACCY position.
Set wiper switch to the PULSE position.
Turn the ignition off when the wiper arms are in the innerwipe position and not moving.
Disconnect the washer hose from the washer nozzle.
Remove the cover from the wiper arm nut.
Remove the wiper arm nut from the wiper transmission drive shaft.
Using J 39822 remove the wiper arm from the wiper transmission.
Remove the wiper blade from the wiper arm.
Clean the knurls of the wiper transmission drive shaft with a wire brush.



Install the wiper blade onto the wiper arm.
Install the wiper arm onto the wiper transmission drive shaft. IMPORTANT: Hold the measuring device at 90 degrees (perpendicular) to the wiper blade tip.
Measure the distance from the wiper blade tip to the solid edge of the windshield blackout. Position the wiper arms at the following distances:

LH - 147 mm (5.79 in) above the glass blackout.
RH - 123 mm (4.84 in) below the glass blackout.

NOTE: Refer to Fastener Notice in Service Precautions.



Install the wiper arm nut onto the wiper transmission drive shaft. Tighten Tighten the wiper arm nut to 48 N.m (35 lb ft) .
Install the cover on the wiper arm nut. IMPORTANT: Lubricate the washer hose with the windshield washer solvent to ease installation on the washer nozzle.
Install the washer hose on the washer nozzle.
Inspect the wipers for proper operation.



Remove the wiper arms from the vehicle.
Remove the air inlet grille panel.
Remove the wiper motor.
Remove the air inlet panel to wiper motor module screws.
Remove the wiper motor module from the vehicle.
Remove the insulators from the wiper motor module.

INSTALLATION PROCEDURE

Install the insulators onto the wiper motor module.
Align the wiper motor module to the air inlet panel. NOTE: Refer to Fastener Notice in Service Precautions.
Install the air inlet panel to wiper motor module screws. Tighten Tighten the air inlet panel to wiper motor module screws to 10 N.m (89 lb in) .
Install the wiper motor.
Install the air inlet grille panel.
Install the wiper arms onto the vehicle.
Inspect the wipers for proper operation.

Hope this helps; also keep in mind that your feedback is important and I`ll appreciate your time and consideration if you leave some testimonial comment about this answer.

Thank you for using FixYa, have a nice day.

There's a special tool called a "crank puller" that has to be threaded in to the crank arms that are on your bike in order to remove them. An inexpensive version of the tool will cost around $10- which is about the same price as a shop would charge you for the work.
If you *do* want to remove them yourself, please be sure to thread the crank puller in perfectly straight and very, very carefully (backing in all the way out and starting over if you encounter resistance). Once you have threaded it almost all of the way in to the crank arm by hand, grab an adjustable wrench and tighten it down before you spin the handle to push the arm off of the bike. (If you fudge it and damage the threads inside the crank arm, you will have to pay a shop to bash them off instead- another special tool is used for that.)

Windshield Wiper Motor Removal & Installation To Remove:
Using the J 39232, remove the wiper transmission from the wiper motor crank arm.

1. Remove the wiper arms
2. Remove the air inlet grille panel.
3. Disconnect the connectors from the wiper motor assembly.
4. Remove the three screws and the wiper drive system module.
5. Using GM special tool J 39232 or equivalent, separate the wiper motor crank arm from the wiper drive ball joint.
6. Remove the wiper motor crank arm from the wiper motor.
   • Remove the rubber boot.
   • Loosen the mounting screw.
   • Tap on the screw with a plastic or leather faced hammer while supporting the wiper motor crank arm.
   • Tap the screw until the crank arm is loose.
   • Remove the screw and crank arm from the motor.
7. Remove the three screws and separate the wiper motor from the module assembly.

To Install:

1. Position the wiper motor on the wiper drive system module assembly. Install the three mounting screws. Tighten the screws to 62 in lb (7 Nm).
2. Install the wiper motor crank arm on the wiper motor.
   • Connect the wiper motor electrical connector.
   • Turn the wiper switch to the accessory position.
   • Turn the wiper switch to the pulse position.
   • Turn the wiper switch off when the wiper motor is in the middle of the wipe cycle.
   • Disconnect the connector from the motor.
   • Maintain a gap of 0.157-0.314 in (4-8 mm) between the wiper motor crank arm and the bracket tab. If the gap is not 0.157-0.314 in (4-8 mm), remove the wiper motor crank arm and repeat installation.
   • Install the mounting screw. Tighten to 142 in lb (16 Nm).
   • Install the rubber boot.
3. Position the wiper drive system module on the vehicle. Install the three mounting screws. Tighten the screws to 68 in lb (10 Nm).
4. Using GM special tool J 39232 or equivalent, connect the wiper motor crank arm to the wiper drive ball joint.
5. Connect the wiper motor assembly electrical connector.
6. Install the air inlet grille panel.
7. Install the wiper arms.
8. Check the windshield wiper operation.

---

Wiper Motor

1. Remove the wiper blade and arm assemblies, as outlined earlier in this section.
   
2. Turn the ignition ON and the wiper switch OFF so the wiper motor returns to the park position.
   
3. Disconnect the negative battery cable.
   
4. Unfasten any necessary retainers and remove the air inlet screen assembly. Disconnect the washer hoses.
   

Remove the air inlet screen retaining bolts/screws ...



... then remove the air inlet screen



Disconnect the windshield washer fluid hose(s)

1. Disconnect the wiper arm transmission drive link from the crank arm using a suitable wiper transmission separator tool.
   

There is a special tool available to separate the transmission drive link from the crank arm



View of the transmission drive link separated from the crank arm

On some vehicles, it may be necessary to remove the nut from the ball crank and remove the crank arm.



Location of the wiper arm ball crank



If necessary, unfasten the ball crank retaining nut, then remove the crank arm

Detach the electrical connectors from the wiper motor. Remove the wiper motor mounting bolts/screws.