T-Type Cooling Fitting issue

[CPBova]

I recently purchased a Pearson 323 with an Atomic 4. I have been having an issue with the T-fitting getting clogged with debris causing the engine to overheat. I have two questions I hope someone can answer.
First, the material that is clogging the fitting looks like flakes of rust. I am hoping that a acid flush will remove this permanently. Has anyone seen this before and is there something else I should do to resolve this issue?
Second, my T-type fitting has four very small holes at the bottom versus a single large through hole. I am considering drilling out two of these hole to provide more clearance for any debris. Is there any reason I should not modify this fitting?

[ndutton]

Before this gets going please confirm that this is the water injection in the exhaust, not the sideplate Tee and that your engine is raw water cooled (no second pump or heat exchanger).

If the premise is correct, I recommend:

• Replace the pictured assembly with one offered by Moyer Marine: http://www.moyermarine.com/cgi-bin/s...=EXHT_01.2_334
• Replace the square machined elbow with a rounded plumbing style
• Perform an acid flush of the engine following the Moyer Marine protocol
• Consider installing fresh water cooling

[Al Schober]

Whether raw or heat exchanger, You need a sea water strainer. I use a Groco ARG-500 - I consider this a miminum. Go bigger if you like.

[CPBova]

The boat has raw water cooling. It does not have a strainer on the inlet. The picture I provided is the fitting that injects the cooling water into the exhaust.

[joe_db]

My water injection pipe is just a pipe - no small holes or blocked end. That looks custom-designed to catch any foreign objects and get clogged.

[Administrator]

My water injection pipe is just a pipe - no small holes or blocked end. That looks custom-designed to catch any foreign objects and get clogged.

+1.

Bill

[JOHN COOKSON]

I'm not totally convinced that the rust that is plugging up the injection fitting is coming from the engine.
If the injection fitting is mounted to an iron pipe (which I assume it is) there is electrolysis between the brass and iron. This would clog the little hole in the injection fitting pronto. IMO it's time to tear the whole shebang down and see what's happening. You could replace the brass parts with something closer to iron on the galvanic series. Stainless steel comes to mind but I don't know which stainless alloy would work the best.

TRUE GRIT