Yamaha F255TXRC Outboard Powerhead Installation

Reinstalling the powerhead onto the upper casing of an outboard motor is not as difficult as it sounds. Work methodically and you should be able to get your outboard put back together in no time. 

Watch the video above and follow the steps below to install the powerhead onto a Yamaha F225 outboard engine.

Tools and Parts – Yamaha F225 Powerhead Installation

Buy Yamaha F225 cylinder head gasket

Buy Yamalube 10W-30 marine engine oil

How to Reinstall Yamaha F225 Powerhead to the Upper Casing

Step 1. Clean the underside of the crankcase and the top of the upper casing so there are no contaminants that could affect the seal between the crankcase, the cylinder gasket and the upper casing.

Yamaha F225TXRC outboard powerhead installation

Step 2. Make sure the two dowel pins are in place in the upper casing and install the new cylinder gasket.

Yamaha F225 outboard powerhead installation

Step 3. Carefully lower the powerhead down onto the upper casing, making sure not to trap any wires or hoses between the two.

Step 4. Apply red threadlocker to the six 14mm long mounting bolts, then install the bolts and washers up through the upper casing into the powerhead and torque them to 30 foot-pounds.

Step 5. Apply red threadlocker to the seven 14mm smaller mounting bolts, then install the bolts and washers up through the bottom cowling into the powerhead and torque them to 30 foot-pounds. 

Step 6. Reinstall the dipstick tube with its O-ring and the dipstick itself.

Yamaha F225 outboard engine powerhead install

Step 7. Reconnect the wiring harness’ electrical connectors and reconnect the breather hoses.

Step 8. Reinstall the two silencer intakes.

Yamaha F225TXRC powerhead installation

Step 9. Fill the engine with 10W30 oil and you’re done.



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