Re: Yanmar Exhaust Mixing Elbows

Blair:

The reason your mixing elbow was clean is because THIS is the square model, the newer design, the $900+ one, the one that does not clog. This is the GOOD ONE. It did not hurt to take a look at it, I just do not want others thinking they need to do this as well if they have the SQUARE model. This SQUARE design mixes the sea water into the exhaust in such a way that it does not build up like the U SHAPED one does. So you really do not need to do this at 1,000 hours. No need.

Good one = square = $900+ usually never needs service or cleaned, it does not build up
Bad one = U shape = $200 needs serviced, changed out because it DOES build up

Hayden

Marko:

I wanted to do that as well, but the square mixing elbow uses a larger exhaust hose. So you need to then add a reducer to fit it back down to the 2" exhaust hose of the U shape mixing elbow. So, I simply have a spare onboard and I plan to replace it it or inspect it every 3-4 years.
The newer engines use the 3" exhaust hose and this allows them to breath a little better as well. Technically, my 3JH2e 38 hp requires a 2.5" exhaust host, but they came with a 2" exhaust. I think that is part of the problem. So, maybe switching the U shape mixing elbow up to the square one is a good idea. I am not sure.

Hayden

No need, that's the exhaust hose and it usually does not clog up. I just replace the top U shaped piece.
Hayden, sailing for Miami

Old ones do not come out easily. It's best to spray them with PB Blaster and let the soak in for 15 min..Then when applying flight pressure, tap the socket with a hammer to vibrate the bolt until it breaks loose.
This helps.
Good luck.
Hayden