If you have a turbo charger, you probably will also have an after cooler in addition to the heat exchanger. Both should be cleaned. However, I think the recommendation from your mechanic to do it at every 600 hours is excessive (find a new mechanic). If both are moderately clogged, you can still have normal operating temperatures at lower RPMs. If it has never been cleaned you may see increases in operating temperature at high RPMs (90% of full load). In the case of the after cooler, the symptoms are not as easy to spot. Since it cools air returning to the piston chamber, if it is failing you might not get top performance from the engine. You could blow out a little more black smoke but it will be hard to tell. A dirty after cooler could also increase fuel consumption and add strain to the turbo charger. Again, hard to tell.
I would suggest scheduled cleanings somewhere between 1000 and 2000 hours. If you are handy with a spanner, this is not a hard DIY job. There are many YouTube videos on cleaning heat exchangers. If you do it yourself, be sure to etch a mark on the inner core so you know how to orient the exchanger when putting it back together.
I am not as familiar with the Volvo as I am the Yanmar. On the Yanmar it is possible to remove the end of the heat exchanger to inspect the inner core without having to remove a lot of other stuff. It should be spotless. Any buildup will impede the performance of the engine.
With best regards,
Super Maramu 2000
Currently cruising: Green Turtle Cove – Abacos Islands - Bahamas
From: email@example.com [mailto:firstname.lastname@example.org] On Behalf Of galacsea2000
Sent: Wednesday, December 23, 2015 10:52 PM
Subject: [Amel Yacht Owners] Heat exchanger and the exhaust manifold elbow on VOLVO
I would be interested in feedback from SM2K or Amel 54 owners (engines with Turbo, not atmospheric) regarding regular intervals for cleaning the heat exchanger and the exhaust manifold elbow.
My engine has 2500 hours and temperature remains constant at about 79 to 80 degrees C (never exceeding 81 degrees C at full throttle) but I was recently told by a Volvo mechanics that the heat exchanger should be open/clean every 600 hours !! Mine was never open, having assumed that, as soon as the heat exchanger would not do its job any more, I would see some increase in running temperature.
All comments most welcome
JP, the UN-mechanics
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