QSM11 repair questions

My initial thought is that somebody took the owner for a ride. $28k to replace the front cover gaskets? I know the front of the engine needs lifted to do this job but that sounds ridiculous.

If the manifolds are not currently leaking and the boat's been propped to keep load and fuel burn down I say you're good. Other than cleaning the coolers and exchangers as you mentioned but honestly that is the best time to repair the manifolds if needed since you're already in that far.

 

Agreed. If they got the fuel burn corrected then you have a much better chance of being good with the manifolds. As some have said, it is a crap shoot whether or not they will leak again. I have been lucky, my boat had around 950hrs last winter when we did all the maintenance to it with VERY little soot showing. I had the manifolds trued up, bolts replaced, ect just because we had everything else off and out of the way. I had bought the boat in 2017 with about 630hrs on it and it was way over propped but had been that way for the first 630hrs with no signs of exhaust leaks at the survey. I immediately brought the pitch down so the last 300hrs were at the correct fuel burn. Most of my cruising is at 2000rpms.

 

@SeaNile, the manifold leaks are easy to spot. Look for black dust where the manifold bolts to the engine. It’s easy to spot against the white engine paint. If you don’t see any, then you should be in good shape. The other repairs that you mention don’t seem normal or routine to me, so I wouldn’t expect to encounter them again.

 

@SeaNile Check your very last three pics. Looks like you could have some coolant leaking out of the fittings. Cummins use blue coolant.

 

Non of the pics are of the area where you would look see the exhaust leaks. You need to look between the heat exchanger and head to see where the exhaust manifolds mount to the head. This is where you would see soot if you had a leak. You are looking for diesel soot around the mounting flanges on the exhaust manifolds.

 

not a Cummins guy so this could be off base but what metal is that flange? It almost looks like oxidation

 

That piping is all raw water. It almost looks like some sort of a sealant; there should be nothing but a coat of lubricant on the O-Rings behind those flanges. I wonder what that is all about....

 

@ttmott...did they use some type of bronze adapter? I blew up the pic, and it looks like it's potentially oxidized with some type of grey lube or never seize as well.

 

I seem to remember those AC closeout plates being bronze. Could be corrosion from a raw water weep.... But it looks odd..

 

Being on the raw water side was exactly my concern. Seeing something that looks like anti-freeze on the raw water side is never a good sign. I suspected some sort of corrosion initially as others have mentioned, but zooming in, the blue stains appear to run down the engine at point of attachment. Anyway, hopefully a simple solution, but I’ve never seen something like that before.

 

>>>>>>>>>>>>>>>>>>>>>>>>

I used this product on a raw water hose that required removal to access a zinc on my Yanmars:

Rectorseal Blue Pipe Thread Sealant 1.75 oz - Ace Hardware

It made the periodic removal so much easier

could be a coincidence, but it looked EXACTLY like what appears in the photo above.

RWS

 

That is concerning that you got two different opinions on the motors. Is there one guy you would trust his opinion over the other?
The chrome piping is carrying seawater from the seawater pump to the inlet on heat exchanger and then from the heat exchanger to the after cooler. I have to assume the blue is seawater corrosion and not antifreeze because I don’t believe there’s any antifreeze at those connections.

 

I agree that looks like corrosion from seawater leaks, strange that all of the connections are leaking though. It also looks like the area where the wiring harness plugs are has been repainted bright white. This isn't a normal area to touch up so was this replaced?

Seems the seawater leaks should have been evident to the owner especially with engine access on a Dancer.

 

Suggest spraying some BRAKLEEN solvent on the mystery blue stuff

If it melts off easily it may just be excess blue sealant shown above.

If it doesn't then you can rule this possibility out.

BEST !

RWS