Maintenance: Yanmar 4JH4AE and ancilliaries
The engine has been very reliable after a minor fuel filter assembly issue was fixed under warranty. It is serviced annually with all usual tasks covering oil and filter changes, impeller, plus additional checks mentioned in the layup and pre-launch checks.
The engine was laid up from October 2019 until September 2021 when it was turned over carefully before starting for a brief test run. It started in under 5 seconds and ran perfectly before being winterised once more i.e. belt and impeller removed, usual treatment with fogging oil in manifolds and inhibitor sprayed inside heat exchanger. Usage in 2023-2025 was very light with only a few weeks afloat in 2024 due to illness.
The following items are worth noting for future preventative maintenance.
Coolant
The engine was supplied with a green, short life variety and replaced by the pink Yanmar long life coolant.
- 5th May, 2012 Initial replacement of green coolant with long life version after 3 years use
- 26th April, 2017 Scheduled 5 year replacement with fresh long life coolant
- 3rd June, 2022 Scheduled 5 year replacement with fresh long life coolant
Another coolant change is planned for 2027 but could be delayed in view of extended storage and light usage post COVID.
Starter motor
Removed in October 2019 to check brushes and found to be in excellent condition with no sign of wear. There were 4 brushes and all had width of 14mm and thickness in range 4.5-4.7mm. Brush heights were 15.9mm, 14.9mm, 14.3mm and 14.7mm with all standing well proud of support slots. The commutator also appeared to be in very good condition. The lack of wear after 10 years use made it reasonable to carry out a follow up after a further 6 years i.e. 2025. However, the engine was laid up between 2020-2022 and the next check isn't due until 2027 or 2028.
Fuel filter assembly
The original fuel filter assembly was replaced under warranty by Swordfish Marine in August 2011. It had an integral pump with faulty seals on the piston and the known defect allowed air to enter the fuel system and caused a minor starting issue.
The replacement does not have the integral manual pump and is self-bleeding. It works well and has never caused any problems.
Volvo shaft seal
The Volvo seal was replaced on 10th May, 2015 by an "engineer" in Agua Dulce. It had never shown any sign of leaking and only replaced as a precautionary measure. I expected the "professional" to use the correct tools but he actually used the same method I would have used with longer bolts. I had to stop him hitting the flange on one side with a large hammer. He didn't know that the bearings are thrust bearings, not designed to handle sudden side loads from a hammer but I was able to make him do the job properly.
The original part showed no signs of wear at all. The replacement is greased annually prior to launch and burped immediately afterwards. It has never shown any sign of dripping either.
