[C320-list] exhaust blockage

[Jeff Hare]

It's really an easy job.

You'll need the exhaust elbow, the threaded stainless coupler and the "L" shaped exhaust port casting that mounts to the back of the engine.  I got those three parts from the local Yanmar dealer and they were under $500.  The other part you'll need is a short length of exhaust hose.  The corrugated/flexible exhaust hose is really easy to work with and won't put nearly as much stress on the muffler.  Don't reuse the one you have, new hose makes the job easy.

- Remove the exhaust cooling line (raw water) that feeds in near the top of elbow.
- Remove the hose clamps from the Exhaust hose that enters the muffler.
- Unbolt the 4 bolts on the cast exhaust assembly from the back of the engine block.  
- If the assembly will twist and come off the muffler, great.  If not, slice the exhaust hose with a utility knife and peel the hose off the muffler fitting carefully.  Take this hose with you when getting a replacement.
- Remove the exhaust hose from the elbow assembly, but don't separate or try to reuse any parts of the exhaust elbow.  It's more useful to keep it just like it is so that you can assemble the new one and match the same angles.  Then the new assembly will just drop in place.
- You will probably need to remove/reuse the little bronze(?) fitting from the old assembly that the raw water cooling line plugs into.  My new one didn't have this.
- I used pipe sealant compound when assembling the new exhaust elbow, but a half dozen wraps of PTFE/Teflon tape would work also.  A vice helps hold parts when assembling the new unit.

I think I had the whole thing put back in the boat really quickly once I got the parts.  It's not difficult at all.

Finally, use a sharpie and write the year on all the parts you changed, so that the next owner of the boat will know how old they are.  :)

-Jeff Hare
#809
Woodbine II
Newburyport, MA


-----Original Message-----
From: C320-list [mailto:c320-list-bounces at lists.catalina320.com] On Behalf Of Steve Turbis
Sent: Friday, November 20, 2015 1:31 PM
To: C320-List at catalina320.com
Subject: [C320-list] exhaust blockage

Has anyone had this problem. I can't get my Yanmar diesel over 1700 RPMs and my mechanic says I have to replace the elbow and manifold because typically this engine builds up soot in this area and the motor can't function properly because exhaust keeps backing into the motor. Any ideas if this is true? He wants to charge about $1000 to repair it.

Steve
"AT LAST"
Dana Point Ca