yanmar 3gm

[razzda]

Hello All, Yanmar 3gm series has an external oil line that lubricates the upper end of the engine valve train. Why it is not an internal thing is beyond my understanding of engine construction. Consequently the steel oil line is susceptible to rust. Mine rotted out two years ago cost thousands in towing and eight hours of gruelling labour to replace. The new unit just rotted out again!!!!!WTF!!!!
The engineering here pales....Nonetheless we have to replace once again.
Any great ideas as to how to rust proof this mother so it lasts a little longer than two years.

Some kind of rubberized bomb proof coating anyone know about.
Really frustrated. Russ

[SY Harmony]

Paint the replacement part to start with. Then I’d address the source of the salt water shower your engine is taking.

[Compass790]

Originally Posted by SY Harmony

Paint the replacement part to start with. Then I’d address the source of the salt water shower your engine is taking.

What he said +1. I painted our external oil line then covered with epoxy reinforced with fibre as the oil line was rusty but not leaking. Oil temp never gets above 60oC in our raw water cooled engine.

[lockie]

I feel your pain brother. The same line on my 2GM let go 10 years ago, but I was incredibly lucky. I had motored against strong winds into the narrow river entrance of a first-time-visit harbou,r at the end of an exhausting 40 hour solo passage (strong winds, lots of ships etc). The following morning I just happened to check the bilge and found it black with engine oil. The level on the sump dip-stick was just below the lowest mark, and when I traced the leak and removed the offending line, the middle section fell apart in my hands. I reckon I made it in with minutes to spare!


But there's more: it was Christmas, with no chance of getting a replacement delivered for a couple of weeks, but one of the locals who stopped to chat on the wharf just happened to be the guy who serviced the fishing fleet. He took the bits home and made me a new line for 50 bucks, and I installed it, topped up the engine then cleaned out the bilge that afternoon. I was incredibly lucky, sorry yours was such a painful experience.


Cheers, Graeme

[razzda]

Thanks all for the input, new part arrives tomorrow, like the sound of epoxy paint.

[SY Harmony]

Originally Posted by razzda

Thanks all for the input, new part arrives tomorrow, like the sound of epoxy paint.

Tape off the sealing surfaces before coating.