'81 Hunter 33 Project: Muffler Replacement

[Rabe]

Well it's been over 6 months since I told you guys about my leaking muffler, Leaking Muffler | Sailboat Owners Forums

Because of the location I asked the yard to replace the muffler with the Vetus NLPH50. They are a vetus dealer after all.

I figured this would be a hell of a job to get out, requiring contortions in front of and behind the gas tank. I also, figured that the existing muffler was strapped in somehow down there. From what I could tell, the whole boat must have been built around this muffler.

Well, they told me that they couldn't find the replacement waterlock/muffler. Okay... so they should be able to find something right?

Finally, after 7 months of hemming and hawing from the shop I decided to get in there and do the job myself.

It took me a good 3 hours but I was able to remove the old muffler. I had to remove my water heater and cut through the exhaust hose to do it but it's out. Sure enough, there was a hole rusted through it.



The existing hose was cracked and needed replaced so there wasn't really anything lost here.

For posterity, here's the dimensions of muffler and hose.

Muffler:
5 1/4" body diameter
18" body length (without inlet / outlet)
2" OD inlet & outlet diameter
2" inlet & outlet length
22" overall length

Hose from engine to muffler. 2" ID, 24" length
Hose from muffler to factory exhaust outlet 2" ID, 55-60" length (I destroyed a section cutting through it)

Today, I was able to find a place in Florida that has the Vetus NLPH50 in stock. At least they told me that what their inventory system says, on the phone. (yes. They answered the phone on Easter)

Going to try and find some decently priced 2" exhaust hose.

 

[heritage]

I replaced my muffler last year with this one: Discount Marine and Boat Supplies - Inflatable Sales | Defender Marine. I am pretty sure that they are made in the USA.

 

[Rabe]

I replaced my muffler last year with this one: Discount Marine and Boat Supplies - Inflatable Sales | Defender Marine. I am pretty sure that they are made in the USA.

How do you like it?

I looked at vernalift mufflers, I was not completely convinced that it would fit under the fuel tank. The smallest diameter is 6.36", over an inch diameter larger than the existing muffler.

 

[RoyS]

I have a nearly identical boat. My muffler is completely different from what you removed. Mine is a Centrex 2" Vernalift Inline muffler. Cost about $300. It is fiberglass 11" long and 6-1/2" in diameter with a drain plug. If you use this model, I suggest locating it as far toward the stern under the fuel tank as you can to provide access to the drain plug. If you do not drain this in the winter then you must charge it with antifreeze which is a pain. I will be posting separately a report on a complete redesign of the exhaust system on my boat shortly when I finish the work.

 

[Rabe]

It is fiberglass 11" long and 6-1/2" in diameter with a drain plug. If you use this model, I suggest locating it as far toward the stern under the fuel tank as you can to provide access to the drain plug. If you do not drain this in the winter then you must charge it with antifreeze which is a pain.

I was really looking closely at this centek model. If I have problems with the vetus being too long to get installed I will definitely return and get this model.

As far as the drain is concerned, is it possible to attach a length of hose with a plug on the end? That may make it easier to access.

 

[Rabe]

Well, I got the muffler (Vetus NLPH50) and new hose (Vetus SLANG50) installed this past weekend. It was easy enough.

I added 3 feet of exhaust hose to the system. The old stuff in it didn't get any higher than the cockpit floor. This height is only a few inches higher than the waterline. Since the thru hull is below the waterline, I was a bit worried about that. I don't know that I needed to worry, the boat was designed that way and is over 40 years old.

The extra 3 feet of hose allowed me to get a loop above the waterline higher than the cockpit floor.

The Vetus hose was simply amazing! I looked at the stuff that was in my boat and what I could find at local shops. These hoses were stiff and hard to bend. The Vetus hose was really easy to bend. I was absolutely amazed.