How to Replace the Starter on a M30 Universal Diesel Engine (+ Tension the Belt) | Catalina Sailboat

January 27, 2023 Sailing YouTubers

In this video we show you how to change the starter and tension the pulley on a Universal M-30 diesel engine.

Welcome back to another Blue Moon Life sailboat maintenance video! In this video we show you how to change the starter and tension the pulley on a Universal M-30 diesel engine. The steps to change the starter are fairly straightforward, but always remember to think about safety first and turn off your batteries and connections prior to working in the engine compartment.
*We are NOT experts* but here are the steps we followed to change the starter:

1. Turn off the batteries and disconnect the battery cables
2. Locate the starter motor on the engine
3. Carefully remove the two bolts/fasteners that are holding the starter in place
4. Carefully remove the wires from the starter, taking note of any wiring connection locations (it may be helpful to take a photograph for when you replace it)
5. Install the new or rebuilt starter in the reverse order, starting by connecting the wires and then tightening the bolts (consider using an extended socket and access the bolts from *below* the motor)
6. Reconnect the battery cables, turn the batteries back on, and test the starter to ensure it is working properly.

It is important to refer to the specific engine manual for the particular engine you have, as different models have different instructions!

As for tensioning the pulley, the process is simple. Locate the tensioning arm and loosen the nut. Apply pressure on the arm until the belt is tensioned properly (it should have approximately a 1/4 inch "play"). Hold pressure on the tensioning arm and fasten the nut again to hold the new level of tightness.

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For anyone new to the channel, we live on a 30 ft sailboat full time and recently moved to an off-grid moorage the summer months! This means that we get all of our power from the solar system or by running the Diesel engine, and we have to pack in all of our water and food using our little dinghy with an outboard motor. Blue Moon is a 1978 Catalina 30 sailing vessel which we acquired in 2020. One year later we decided it was time for a road trip and built out a 1998 Delica to drive across the country. Now we live aboard the boat full-time, take weekend trips in the van, and explore this beautiful world.

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Blue Moon Life

Blue Moon Life
  • Joined: November 30, 2020
  • Subscribers: 22,200
  • Videos: 147
  • Views: 2,385,740
  • Victoria, BC, CA
  • Language: EN

Jonas and Gillian from the SV Blue Moon share an honest look at the benefits and challenges they are facing as liveaboards and share stories and videos about sailing, liveaboard, travel, and alternative living.