[C320-list] Trident hump hose for 2" OD exhaust hose

[danny jensen]

Walter,
I would recommend getting a new muffler from Catalina and if your mixing elbow is about 7 years old, do the elbow too. I don't like the idea of my floor boards floating when I'm on my long trip.

I am also using the trident flex (see below) *and* the hump hose detailed below. Trident flex sort of flexible but I like the added flex of the hump hose. You also may want to consider putting some rubber (like a yoga mat/neopreme ) between the muffler and the null. 

Here are my project details reposted.

1.        I turned off the raw water thru hull,  disconnected the 3/8 hose connection at the elbow, the 4 riser exhaust bolts came off with no problem. Then I disconnected the elbow from the 2 in. exhaust hose. I used a radiator hose pick to remove the hoses. They came right off with no problem. Don't sweat removing the hoses. 

2.        I took the old elbow assembly home where I used it for reference to create the new assembly using a vise. I don't believe you can create the new assembly without the help of a vise and 2 large adjustable 15 in wrenches. Don't try to make the new assembly on your boat! You will need to twist the 3/8 in input 180 degrees then you will need to create the exact same angle as the old elbow by threading the joint into the elbow and exhaust riser. I used high temperature anti seize on the joint threads before assembly. 

3.        I used a gasket scraper to easily remove the old gasket. Then I applied some high temp gasket seating material to both sides of the new gasket and bolted the elbow assembly to the motor. 

4.        I removed the 4 stainless screws securing the muffler to the boat and I removed the output exhaust hose from the old muffler using the radiator hose pick. The hoses come off the muffler without any problem.  The muffler comes out of the boat without any problem. 

5.        I put the new muffler in place and connected the output exhaust hose without any issues. I found the screw holes on the new muffler did not match the screw holes on the muffler.  I could get the 2 screw holes forward to line up but then the aft screw holes with not align with the existing holes. Access to the forward inboard screw is somewhat limited so you will want to match the forward inboard screw with the existing hole then use a drill motor to self tap new holes with the muffler in place. The existing self tapping screws were in good shape and I did not need to drill pilot holes, I just drove the screws into the glass with the muffler in place after I screwed down the forward screws. Apply a good amount of silicon grease to the muffler drain. 

6.        I used a sawzall to cut an 8 in and 13 in segment of corrugated exhaust hose then I joined them with a hump hose using double hose clamps on each side of the hump hose. Then I connected the hose to the mixing elbow and the input side of the muffler. 

7.        I turned on the thru hull and ran the engine. White fiberglass chips from the new muffler were spitting out the exhaust for a while. No leaks. The hump hose appeared to do the job limiting vibration. I left the rear engine cover off and took the boat out in open water and ran the motor up 3000 RPM. I went below and to my surprise I saw smoke coming from the exhaust riser side of the stainless steel joint nut!  No water. It appeared that the joint was oozing and burning anti-seize.  After about 10 minutes this smoking stopped.  I'm assuming this is normal but it spooked me. I'm going to put a co2 monitor in the aft cabin to make sure I don't have gas leaks. 

Parts: 
bayshore marine: 
128370-13201 gasket     $4.92 
124070-13520 U mixing elbow    $169.33 
128370-13610 riser exhaust     $130.39 
104214-13580 joint                 $28.79 
Note: 
27233-250000 plug            comes with 124070-13610 
124070-13300 elbow 3/8    comes with 124070-13610 

Parts from Catalina Yachts (K... at catalinayachts.com) 
1 Muffler $374 plus Shipping 

Parts from Catalina direct: 
High Temp Anti-Seize Compound (#Z2858): 1 
Item Total: $15.95 
Exhaust Hump Hose 1-5/8"I.D X 6" (#Z2152): 1 
Item Total: $31.49 

Tools Harbor Freight 
8" Radiator Hose Pick $3.99 
Carbon/Gasket Scraper $2.99 
High Temp Gasket seating compound 

MMI Marine 
TRI252-2004 
TRIDENT CORRUGATED FLEX SAE J2006 MARINE WET EXHAUST HOSE (HARD WALL WITH WIRE)  - 2 Feet  $15.00 
BUA70HSS36C 
BUCK HOSE CLAMPS S/S FROM 1 13/16" TO 2 3/4"        4 $8.00

Danny
#972


-----Original Message-----
From: C320-list [mailto:c320-list-bounces at lists.catalina320.com] On Behalf Of Walter Schaffer
Sent: Monday, July 07, 2014 8:37 AM
To: C320-List at Catalina320.com
Subject: Re: [C320-list] Trident hump hose for 2" OD exhaust hose

Jeff, thank you. There is a Yanmar engine/parts shop in Annapolis. I'll stop there.
Walt


On Monday, July 7, 2014 7:42 AM, Jeff Hare <Catalina at thehares.com> wrote:
 


Maybe I might make another suggestion.  

When we replaced our hose (and elbows) this spring, the Yanmar guy suggested
I use the flexible exhaust hose instead.  I used "Tridentflex Corrugated
Hardwall Marine Exhaust Hose".  It's a bit more money than the regular hose
but so much easier to bend and looks like it puts no stress on the muffler.
It's still wire reinforced but I think with this, you won't need the hose
hump and the extra connections that introduces because the whole hose
becomes a hose hump.  It's such a short run anyway.

Find a marine shop and feel it for yourself.  They say they use this almost
exclusively now because the mechanics love it and it holds up every bit as
well as the old stiff stuff but absorbs the vibrations.

-Jeff


-----Original Message-----
From: C320-list [mailto:c320-list-bounces at lists.catalina320.com] On Behalf
Of Walter Schaffer
Sent: Saturday, July 5, 2014 7:35 AM
To: c320-list at catalina320.com
Subject: [C320-list] Trident hump hose for 2" OD exhaust hose

I'm having my fiberglass aqualift muffler repaired (again), and I'm trying
to find a Trident hump hose to fit my exhaust hose to eliminate some
vibration.
My exhaust hose for Yanmar diesel is 1 5/8 ID and I believe about 2" OD.
West Marine and Defender catalogs only show 3" ID. I believe this size will
be too large?
Anyone know where to get a smaller hump hose to fit my 2" OD hose?

tks Walt Schaffer
#515 Middle River, MD
Bohmenian II