Old Yanmar Diesels and Repowering

[TomandAnitas34]

I have searched around the forums here and other places and never got a real perspective on when to replace old engines. The only relevant post I saw was a guy in Texas who was patching holes in the salt water cooled engine block, with JB weld. His was a 30 year old Yanmar. My Yanmar 2QM20 will be 33 years old when I finish the overhaul and I'm gonna repower with a 6 year old 2GM20. I do this because of shaft seal age as well as corrosion. My motor has been in the north, pulled out on the hard, and filled with antifreeze for 7 months a year, probably cut the corrosion by 25% over one left in for years on end, but that's just speculation. So how old is your Yanmar ?

[Inlet Marine Services]

Something to think about is that 2qm20 is a linered engine so if parts are available then it would be a very good option for rebuild. You can also install a heat exchanger add-on kit. Very good motor and can last you many more years.

[TomandAnitas34]

Well, you are right. If the cylinder liners can be pulled and re-installed. If the O-rings seal in the water jacket and do not leak water into the oil. Then the parts list:
Pistons
Rings
Main crank bearings
Rod bearings
Cylinder liners
Gasket set
Valves
Valve guides
Valve springs
Complete seal set
Oil pump
Fuel pump
Starter motor
Injectors.
Sounds like more than $1800 at Yanmar prices. Am I wrong here ?