2QM15 Exhaust System

Oct 8, 2019
2
Watkins 27 Key West
Hi! I moved to Key West about a year ago against my will when I bought this headache of a Watkins 27ft. The seller was dishonest, I had someone check the boat out and you get what you pay for lol. They missed a lot of important things like..the boat not pumping water.

When I realized I couldnt move the boat I was in a pinch with the marina (who rented my slip out already with a boat in it) and I was like well shite. I bought a $675 dinghy and drug it out to the flats so I never once saw the boat overheat. The dinghy never worked again I had a charter boat throw me a favor and get me to a boat yard. Where I decided, well I have to fix it then. Got established with a job while I was there and basically just shut down my business and started it here in Key West.

Now with the backstory outta the way...I pulled it out of the water. Prob hadnt been out in six years. Relaminated the keel, fixed keel cracks and re bonded the ballast to the main. I have no idea what I'm doing but I apparently did a good job alone.

SO. After putting a new transmission on the thing, a new sea water filter, a new water pump while it was out - I splashed it and it is pumping! But, its gaspy coming out back there. This engine is a mess for sure. But I got whammed by a crappily anchored 40ft yacht not too long ago and its nice to have one that works well. Not to mention, when I sell this thing, Id like to make sure the buyer is not as screwed as I was.

I recently put a new alternator on it and changed the gasket behind the alternator mount. It cranks immediately. I dont know how, but it does. Anyway - back to the exhaust manifold. I am totally lost with it but all things Ive currently replaced that seems to be the final culprit for the restricted flow coming out of the back. It really needs that new manifold, probably a new mixing elbow. I do not know if the one I have is a serviceable or salvagable part - I am guessing by the looks of things there that disturbing it could prove fatal - how do I find an exhaust manifold for the 2qm15?

I can gladly get some pics of it. That backside of that engine would scare the crap out of anyone.
 

RoyS

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Jun 3, 2012
1,742
Hunter 33 Steamboat Wharf, Hull, MA
Doubtful that the exhaust manifold is the restriction problem. That manifold has a bypass that allows water flow around it until the thermostat opens. The exhaust elbow is readily available from Yanmar dealers. You seem to share in Biblical Jonah's luck. I would never go to sea with you.
 
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Likes: kimmiedeanne
Jan 7, 2011
5,732
Oday 322 East Chicago, IN
You say that the exhaust flow is “gaspy”. Do you mean it flows in spurts ?

On my 2GM20 engine, that is normal. It is not a steady, consistent flow of water out of the exhaust.

Water and pressure from the exhaust build in the water-lift muffler, then spew out.

Sounds like you have a lot of issues, and maybe you can get some good advice here. But help us out with photos of specific issues.

Good luck.

Greg
 
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Likes: ggrizzard
Oct 8, 2019
2
Watkins 27 Key West
Doubtful that the exhaust manifold is the restriction problem. That manifold has a bypass that allows water flow around it until the thermostat opens. The exhaust elbow is readily available from Yanmar dealers. You seem to share in Biblical Jonah's luck. I would never go to sea with you.
I would never go to sea with me either!!
 
May 27, 2004
2,057
Hunter 30_74-83 Ponce Inlet FL
Kimmie, I'm in Daytona...
I'll sail with you when I get to the Conch Republic this winter
 

MitchM

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Jan 20, 2005
1,031
Nauticat 321 pilothouse 32 Erie PA
i give the author a h$%^ of a lot of credit for successfully taking on these projects after a shifty owner and not too great surveyor left him/her w/structural problems. an engine survey is always 'extra' , apaprently wasn't done , and obviously is a wise idea. having frittered away much of my wasted youth as an engineering student windsurfing and sailing out of key west , i guarantee you there are some great people, mechanics, and sailors there. i still gravitate down there when i get a chance, ( but don't have to sleep in a van or on the beach any more. )