Pearson 365 and 367

Pearson 365 and 367 => Pearson 365/367 Mechanic Shop => Topic started by: S/V Laelia on May 20, 2013, 12:52:09 AM

Title: Exhaust system
Post by: S/V Laelia on May 20, 2013, 12:52:09 AM
The last time I was out sailing, I noticed the smell of exhaust in the cabin. Today when I was checking out the installation of the new sea water pump, I noticed water dripping from somewhere else. I found the source and also spurts of what looked like and smelled like exhaust. It looks like there is a crack in the part of the exhaust system shown below.

(http://i1151.photobucket.com/albums/o638/SailorRalph/Exhaustleak_zpsbfabdc1c.jpg) (http://s1151.photobucket.com/user/SailorRalph/media/Exhaustleak_zpsbfabdc1c.jpg.html)

I took a look at the W40 engine manual and it says not to hang anything weighing more than 8 lbs. off the exhaust port. This monster looks like more than 8 lbs. There must be a simpler way. Is there some common setup that I can order or put together to replace this?
Title: Re: Exhaust system
Post by: S/V Deo Volente on May 20, 2013, 07:57:17 AM
The setup isn't unusual, partly due to different installations and making sure it's above the waterline.
The mixing elbow is available
http://shop.torresen.com/ships_store/?p=details&ident=517168 (http://shop.torresen.com/ships_store/?p=details&ident=517168)
and the rest is generally galvanized pipe, which should be replaced periodically. I had a crack in the pipe fittings  few years ago, the biggest concern was getting the pipe out of the exhaust manifold cleanly.
Title: Re: Exhaust system
Post by: S/V Laelia on May 20, 2013, 10:50:40 AM
That's a relief - I was afraid this was someone's personal bad idea.

Any tips on how to get the old parts off without leaving portions of bolts embedded in the engine?
Title: Re: Exhaust system
Post by: S/V Deo Volente on May 20, 2013, 11:10:59 AM
The best case is to put a pipe wrench on it and unscrew it. In my case I used a saw all to get the majority of it off, but leave enough in the exhaust to put a wrench on. Then I cut a slot on the inside of the pipe so I could beat on the pipe and get it to collapse then it came out . I do have a W50 but the exhaust is pretty standard.
Title: Re: Exhaust system
Post by: S/V Laelia on May 20, 2013, 11:09:50 PM
Sounds like all sorts of fun!

Does your installation have a rigid connection from the exhaust to the injection elbow? Is the elbow supported in some way besides the connection?

Mine is just hanging out there with no visible support other than the connection to the exhaust on the engine.
Title: Re: Exhaust system
Post by: S/V Deo Volente on May 21, 2013, 06:45:56 AM
It's all galvanized pipe, so yes it is rigid. Since the water is used to cool the exhaust you wouldn't want hose before the mixing elbow.
Title: Re: Exhaust system
Post by: S/V Laelia on May 21, 2013, 11:19:56 AM
OK - thank you for all of this. I don't have a whole lot of mechanic experience and I live in fear of what I don't know.  :)
Title: Re: Exhaust system
Post by: PeteW on May 22, 2013, 11:47:58 AM
Over time the wet exhaust hose will become brittle, develop small fissures and leak steam and carbon monoxide gas into the cabin. Its odorless, so its what you are not smelling which gives me greater concern. In reviewing your picture I can only assume that you removed the hose clamps but there does appear to be one waterpump hose that is leaning against the hot exhaust where the heat tape is gone. It looks burnt. Perhaps that is what you are smelling.

Anyway it all will need to be replaced eventually. The biggest problem will be removing the nipple from the exhaust manifold. On my westerbeke (W58) the exhaust manifold is aluminum. My mixer/ nipple is one piece custom stainless. The easiest way to work on all of that is to remove the exhaust manifold at the flanges to the motor. That will actually the easy part. Sawing the nipple to colapse it will be critical in order to save the manifold.  I have the pleasure of replacing everything including the manifold (beyond repair due to corrosion) for a parts pricetag of around $1.6K.

Pete
Title: Re: Exhaust system
Post by: S/V Laelia on May 23, 2013, 01:08:36 AM
I should have mentioned in my writeup that I had started to take it all apart. I removed the hose clamps and started to remove the heat tape before I ran out of time and energy. That's where things stood when I took the picture.

I had just started the engine when I was looking at the mixer elbow and I could see occasional puffs of smoke coming from the crack in the elbow. That's probably what I smelled. At any rate, I won't be running the engine again until the problem is fixed.

I will be working on pulling it all apart this coming weekend. I'm not looking forward to it!