I completely TRANSORMED this Yanmar 3GM but will it START?!

Name: I completely TRANSORMED this Yanmar 3GM but will it START?!
Uploaded: 2025-11-03T20:18:31.000Z
Duration: 24 min 56 s
Description: John restores a Yanmar 3GM engine, correcting piston-to-head clearance and verifying fuel injection timing before start-up.

November 3, 2025 · 24 min · 26K views

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What this video covers

John restores a Yanmar 3GM marine diesel engine, focusing on correcting piston-to-head clearance and verifying fuel injection timing before final assembly and painting.▶ 0:09 After measuring an initial clearance of 46 thousandths of an inch—exceeding the 27-to-35 thousandths specification—he replaces the aftermarket head gasket with an official Yanmar OE gasket.▶ 0:46 This adjustment brings the clearance to 33 thousandths of an inch.▶ 10:31 He verifies fuel injection timing by using a manual procedure to observe fuel movement at the pump while rotating the crankshaft, confirming the original shims provide correct timing.▶ 5:34 For the exterior, he applies an AkzoNobel epoxy primer followed by a high-gloss Allcraft 3000 polyurethane top coat to protect against fuel and oil.▶ 11:18 During the initial start-up, he uses a mechanical gauge to confirm oil pressure after the stock Yanmar low-pressure switch fails.▶ 21:06 The engine runs successfully, though it produces minor white smoke as the new rings seat.▶ 23:12

Boats in this video

Liberty 458Their boat