Sabre 28: diesel maintenance

Our Sabre was repowered with a Beta Marine 14.  We don't have a sure idea when this happened but our guess is around 2005.
The engine looks to have low hours.
The installation was well executed with proper fuel and raw water plumbing.
It has a dripless shaft seal (a big plus.)
When we got the boat we immediately replaced the impeller even though it looked to be in fine shape.  We also changed the fluids.
I haven't owned a boat with an inboard diesel but to my eye, the water flow out with the exhaust seemed low.  The last few days, we removed the heat exchanger and pickled it with a dilution of muratic acid.  This cleaned off significant scaling.   We also removed and cleaned the raw water strainer.  Once all was back together, there was no discernible change in the flow.  I then started testing each passage the raw water passed through and fairly quickly found the problem.

The clogged tube that leads raw water from the  impeller pump to the heat exchanger.

In a previous impeller replacement, the debris of a disintegrated impeller was not removed from the tube leading to the heat exchanger.  It was 85% clogged with rubber shrapnel.  This evening we are fishing out the last of this debris and expect a decent flow the next time we fire up the iron genny.

The newly cleaned heat exchanger.

The heat exchanger is the rectangle the cap is attached to.

This is a cap with a vented loop.  This is on the rear of the unit as the water is headed  back to sea.

Back it the correct location.

Another view of the rear cap showing both the old and new zinks.
This part as well as new o-rings were purchased at Beta Marine of Minnesott Beach, NC.  It is handy to have the North American headquarters of Beta just around the corner.