Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
1978 Mazda Cosmo Automatic TransFACTORY OEM SERVICE PROCEDURE
Pressure Relief Valve
- Valve may be replaced only if valve is mounted in pump housing. Remove pump and place on bench. Do not hold pump by clamping in vise. Using a steel bridge and a gear puller, valve may be removed.
- Insert new valve into mounting hose. Place a block of wood over valve and tap with hammer until valve shoulders lightly in housing. If pressure plug is installed in new relief valve, remove this plug before installing valve. After valve is installed, install pressure plug.
Factory Service Tools
Use the Manual With the Right Hardware
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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