Raw Water Tube Leak - QSM11

Four Suns

Not a pot stirrer
TECHNICAL Contributor
Oct 4, 2006
10,533
Williamsburg, VA
Boat Info
2003 480 DB
Engines
QSM-11 Diesels
After getting the engines flushed with Rydlyme, new impellers installed, and new zincs put in, I discovered I had a leak in the polished stainless tube that connects the aftercooler heat exchanger to the coolant heat exchanger on the port side engine. Here's a shot of the tube I pulled off the engine:

IMG_2490.jpg


Ain't it purdy? The weld on the upper zinc has a small hole in it and you can see it in the close up (it's the little rusty spot on the weld joint):

IMG_2495.jpg


It looks like a bad weld... the rest of the tube is in great shape and when you look inside, it just looks like they "missed a spot". I'm not sure though... I'm going to take this in and get it welded and keep it as a spare. I ordered a new one and the darn thing was $500! I didn't want to chance the welding thing though. I welded up a hole on an exhaust tube last year and by the end of the summer, the thing turned into swiss cheese...

By pulling that tube off, I got to see the condition of the heat exchangers in the turbo after cooler and coolant side:

Here's the turbo aftercooler:

IMG_2483.jpg


and here's the coolant heat exchanger:

IMG_2484.jpg


That Rydlyme does a nice job keeping these things clean on the raw water side. This is a picture of the fuel cooler on the same circuit and it's never been flushed:

IMG_2507.jpg


That fuel cooler has been replace and you can see that story in my other post.

It's important to keep the raw water circuit in tip top shape...

Just another FYI post.
 
I went and picked up the new pipe at Cummins Atlantic today. They had a new part number that replaced the old one. The new pipe seems to be lighter than the old one so maybe it's a different material? Who knows.... I did ask the guy how many of these he has sold in the last year and he looked it up and said "five counting yours". It appears that this is not just a "fluke" but something one has to watch out for. Maybe that's why they have a new version.... either that or they found a way to make it cheaper. ;-)
 
Here's a shot of the new tube installed:

IMG_2580.jpg


The big white housing with the fins on it is the aftercooler. Seawater enters the top and comes out the bottom. The tube that had the small hole in it was the u-shaped tube going from the aftercooler to the coolant heat exchanger. The raw water cooling system is all clean and ready to roll.

For those of you with a good eye, you can see in the far right side of that picture that the front gear gasket is leaking oil... that's a whole different story.. That's getting fixed tomorrow.
 
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Gary,
The amount of corrective and preventative maintenance you have going on on all fronts is beginning to scare me.....:wow: Please tell me this is because of where you live, how much you use the boat or something like that!
 
Ed

I don't want to scare you, but, Monday I replaced the forward A/C unit ($2500), Tuesday I ordered a starboard shaft (probably gonna cost $1000) and today sent the wheels out to find 500 rpm (who knows what that's gonna cost). Week before last I replaced all of the coolers (transmission and oil) and flushed a transmission that got seawater in it from a failed cooler.

Tomorrow night I am installing the new shaft. Friday I am installing the rebuilt wheels and Friday afternoon I am taking my guys from work riding around the Bay 'cause without their hard work I couldn't afford to do this.

And I am gonna do it all with a big smile on my face because I AM OUT ON THE BOAT!!!!
 
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Maybe I'm just the stupid one for posting all this stuff with pictures. ;-)

But geez... that's a good lookin' engine.

And also, I did things like replace the fuel coolers BEFORE they failed... I don't want to wait till something stops working as we go on these month long cruises and things are not allowed to break or my wife will leave me.
 
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Nawwwww
Your motor looks so good it should be in the movies.

Agreed on replacing things before they break. It is almost always the best course of action. I bought the boat in March of '07 have been going through the entire boat trying to make sure everything is working/up to snuff. The cooler failed before I got to them. The A/C and cracked shaft are items I am replacing before they failed. Can't find it all though. Wife already left so I guess some of my stuff can break on a trip! :)
 
Well I am already feeling the increase in basic maintenance from the increase in systems/size/stuff - expected this to some extent. I am really impressed (and terrified) by the preventative maintenance you all do on things within the item called "engine". I'll get there - just going to take some time.

Gary - appreciate the detailed info - very helpful - keep the photos coming and have a great cruise.
 

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