Carbon Build Up

[nveater]

So I removed my 22 year old mixing elbow to replace and the passageway (exhaust manifold ?) where the elbow attaches has carbon build up- any tips on how to clean that out ?

Thanks

 

[BlowMeAway]

Isopropyl alcohol (IPA) and ultrasonic cleaner bath. Otherwise pipe cleaners and IPA.

 

[kloudie1]

If thick enough to worry about, 1/8" or so, a punch or small chisel used as a scraper.. gently

 

[nveater]

Thanks I'll be armed and dangerous tomorrow with chisel, alcohol and cleaning rags

 

[whatfiero]

Hardware stores sell boiler brush a wire brush on a flexible stick I cut off handle and put on battri drill

 

[JamesG161]

If thick enough to worry about, 1/8" or so, a punch or small chisel used as a scraper.. gently

Unless it is much more than a coating or minor clumps, DON'T REMOVE IT!

Your engine exhaust gas contains "Acidic gases" and engine soot (like a coat of paint) will provide some protection to the steel, as does rust.

If you already labored to clean, don't worry it will return.
Jim...

 

[seadaddler]

If I remember last time I changed my mixing elbo I used many different tools to clean
and I think maybe my favorite heavy duty wire brush on my portable drill and some different
scrapers and as doing this I used my small shop vac to suck out any dirt.
Nick

 

[nveater]

Thanks-to all I took off the main stuff and vacuumed out the clumps, but it still has a nice patina- I then installed my new mixing elbow (with a new gasket) which was easier than I expected -however it will be a few more weeks until the boat is in the water. The boat is 22 years old and this is its first new mixing elbow so I am curious to see the results

 

[Dave Pawloski]

I have a 1985 H-31 and over the years have had some issues with the mixing elbow, especially at the beginning of the spring season.
The local yacht yard suggested that the problem (rust buildup) is caused to some extent by non-use (as in 4 month winter layup). After cleaning the elbow they installed a 2-way valve with 2' of hose
(curled up and tied when not in use) on the raw water engine intake line (should be an easy enough DIY project).
The valve enables me (prior to a period of non-use) to cut off the seawater coming in to the engine and to draw in instead, anti-freeze/coolant. This displaces the seawater in the lines and reduces the potential for rust buildup.