Removing heat exchanger tubes still such a PITA on D2-55F?

[Krumelur]

I want to give my heat exchanger an inspection and was inspired by this video: https://youtu.be/49-UiRPoeyM?si=dfhbh7K8K8dY0P3S&t=706

The thing is that the guy has to disassemble half of the engine to get the tubes out. When I look at my D2-55 manual it appears as if the tubes are supposed to be removed towards the bow whereas he's trying direction stern.

I have the D2-55F installed and wonder if anyone has done this inspection and can talk about it?

[Yngmar]

I've done it on the MD22 and can tell you it's usually sufficient to take the end caps off and clean the tubes with a rod (push through carefully), as the dirt is on the inside (where seawater flows), not on the outside (where there's only nice clean coolant). Also on the ends, which are easily cleaned with a scraper or wire brush. Definitely want to replace the o-rings. I assume the D2-55 is quite similar.

[Krumelur]

Good advice. I may start with that then. I have the new o-rings already here but also got the gasket for the heat exchanger, just in case.
If you have information about the tube/rod diameter that would be awesome, so I can get something suitable here before looking for an old stick on the beach ;-)

[Archer]

We found a package of drinking straw cleaning brushes that let us find a good fit for light cleaning.