QSM11 Heat exchanger and aftercooler maintenance costs

Jeremygavin

Well-Known Member
Mar 6, 2012
2,054
Cape Cod, MA
Boat Info
2011 520 Sedan Bridge
2016 Sea Ray 19 SPX OB
2019 Walker Bay Generation 340
Engines
Cummins QSM11s
Mercury 150 Fourstroke
Honda 40hp
I am having the yard do some maintenance this winter. The motors have about 850hrs on them. I was told the heat exchangers and aftercooler a were serviced at around 600hrs but I couldn’t get the paperwork on it so who really knows.
They have gotten both engines apart and sent me a quote for $9500 in parts. One of the aftercooler housings has many stripped threads and some broken bolts so they are saying that it is cheaper to buy the new case. That cost also includes having the exhaust manifolds squared up at the machine shop and parts for setting the overhead (valves and injectors). Then he told me I would be in the range of $12,000 in labor. That seemed really high to me. Their labor rate is $115hr so that’s about 104hrs of work. I know there is a ton of work involved and I want it all done right but man that is going to hurt. If you have had this service done on your QSM11s what did you pay for the work?
 
Jeremy:
I had both port and starboard aftercoolers serviced, valves adjusted, Racor's rebuilt and both exhaust manifolds replaced. Manifolds (new) for each side $6k +/- We had a couple broken bolts on the after coolers and manifolds but didn't need to replace the case.

Attached receipts...
 

Attachments

  • Inv_3908_from_Shore_Power_Solutions_4956.pdf
    601 KB · Views: 338
  • Inv_3908_from_Shore_Power_Solutions_3948.pdf
    591.6 KB · Views: 248
  • Inv_3432_from_Shore_Power_Solutions_1568.pdf
    604 KB · Views: 223
Last edited:
I've personally read quotes for manifold replacement on qsm11's the final quote was 13k but there was a 2000$ uptick included in that 13k for covid . Blew my mind
 
If I remember correctly it was 90%labor and travel only parts needed was gasket and bolts and resurfacing the manifold
 
I had an independent mechanic who is a good friend of mine do my Port engine last spring. We skimmed the manifold here at my shop.

32 hours labor
$5100 in parts which included a new circulation pump and turbo, would have been about $2000 for just hoses, gaskets, bolts, clamps etc...

He's doing the STBD engine this spring.
 
So what is the accepted interval for Flushing vs complete disassembly for inspection of the aftercoolers these days. I've gotten some conflicting data. (I'll probably post this on boatdiesel as well and prepare myself for flames...)
 
Sorry I never thanked you guys for your posts. I think from what you have said I am not that far off on cost, maybe a bit high. It will be good to have the service done so I know I am good for 5-6yrs.
 
Jeremy:
Did you get everything squared away?
 
I had an independent mechanic who is a good friend of mine do my Port engine last spring. We skimmed the manifold here at my shop.

32 hours labor
$5100 in parts which included a new circulation pump and turbo, would have been about $2000 for just hoses, gaskets, bolts, clamps etc...

He's doing the STBD engine this spring.

That's a good friend to have! I might be in the same situation this fall if this purchase goes through. It'll need a little preventative maintenance to get up to date on everything.
 
Jeremy:
Did you get everything squared away?
Yes, it is all back together. Looks clean and neat. Total was about $20k when it was all said and done. I will be going in the last week of April so I will see then if there are any issues with the work.
 
Last edited:
Yes, it is all back together. Looks clean and neat. Total was about $20k when it was all said and done. I will be going in the last week of April so I will see then if there are any issues with the work.
JG - all in all, that's comparable to my MAN major service (heat exchanges and charge air coolers removed and cleaned), full engine oil/filter/fuel filter/impeller service, transmissions/filters, and genny full service...
 
JG - all in all, that's comparable to my MAN major service (heat exchanges and charge air coolers removed and cleaned), full engine oil/filter/fuel filter/impeller service, transmissions/filters, and genny full service...
That’s good to hear. There were quite a few parts to be bought including one of the aftercooler housings so that is what brought the bill up quite a bit over what I was expecting. I told them I wanted it 100% so go ahead and replace what needed to be.
 
MAN gets a fortune for some parts. I recall each heat exchanger takes 24 small O-rings (MAN calls them “toric seals“ – I love that name), and they are $22 EACH! So I want you by 48 of those, you’re talking some real money. They look like regular O-rings to me, but what do I know.
 
Last edited:
Someone was trying to compare the interval maintenance between the QSM11 and the MAN engines based upon what @Jeremygavin has invested. Keep in mind that the QSM11 suffers from exhaust leak issues due to operating in the wrong part of the fuel curve. This is a one time fix and not maintenance which can range from $2K to $3K in the cost. The only time to do the exhaust repair is during the major cooler maintenance as that is the time to access. The other major cost is the replacement of the aftercooler housing which I'm sure he has at least $2K invested and that again isn't maintenance. So you could probably reduce his costs by $5K for the maintenance interval bogee.
 
Someone was trying to compare the interval maintenance between the QSM11 and the MAN engines based upon what @Jeremygavin has invested. Keep in mind that the QSM11 suffers from exhaust leak issues due to operating in the wrong part of the fuel curve. This is a one time fix and not maintenance which can range from $2K to $3K in the cost. The only time to do the exhaust repair is during the major cooler maintenance as that is the time to access. The other major cost is the replacement of the aftercooler housing which I'm sure he has at least $2K invested and that again isn't maintenance. So you could probably reduce his costs by $5K for the maintenance interval bogee.
That was me Tom - just looking at the total amounts...Nobody can overprice rubber O-Rings like MAN! - and call them "toric seals"!!

But to be fair - My engines are 15L and V-8's, so twice as many turbos/risers, etc. just due to the configuration. But MAN "are" proud of their parts!

They now have a 1200HP V8 that adds two more turbos (dry) per engine - now 4 - and it puts out more than the traditional 60 HP per Liter, so I wonder how it will hold up.
 
Last edited:
That was me Tom - just looking at the total amounts...Nobody can overprice rubber O-Rings like MAN! - and call them "toric seals"!!

But to be fair - My engines are 15L and V-8's, so twice as many turbos/risers, etc. just due to the configuration. But MAN "are" proud of their parts!

They now have a 1200HP V8 that adds two more turbos (dry) per engine - now 4 - and it puts out more than the traditional 60 HP per Liter, so I wonder how it will hold up.
It wasn't you Carter - in another thread is where I saw the reference; too lazy to go find it. Your O-Ring replacement is part of the maintenance interval right? Tom
 
Maybe you’re thinking of my post in the Ask the Captains forum asking for information on the costs for M1-4 and A1-2 maintenance for the MAN R6 800.

I’m thinking of buying a boat with those engines, after almost buying a boat with the QSM11s, so I’m trying to learn as much as I can about all these issues. I get that these two engines are apples and oranges from the repair and maintenance perspective, but I thought the earlier post on this thread loosely comparing them in dollar terms was interesting.

There seems to be some debate on the diesel forums whether down propping is actually a final solution to avoid having to deal with warped manifolds on the QSM11. People I know who have the QSM11s on different boats have related different intervals for the problem surfacing. From what I’m told, some have been very lucky, while others have not. So I’m not certain how “regular” that requirement could turn out to be in a given situation, particularly where the boat in question may already be near too much for the engines. For example, Sea Ray was offering QSM11s in the 510 Fly (though apparently over propped), which seems like it may be a reasonable package for that boat considering it was an upgrade from the standard QSC 8.3. By comparison, Ferretti was putting QSM11s in their 55 bridge boat, which seems like it could be a heavy load for that engine considering they went with MAN i6 800s in later model years. I’ve not seen any data on GPH at specific RPMs with QSM11s in that boat, but it would be an interesting comparison.
 
Last edited:
We’re having repairs done to both motors including aftercoolers, heat exchangers valve adjustments and I’m sure there will be some other costs when they take them apart. I Would LOVE to hear from someone, ANYONE that has successfully repaired these exhaust gaskets anyone bueller? I know guys that have used the “new” gaskets, longer bolts, pitched and cupped props, you name it that still leak. Majority of my operating rpm’s literally while in the NE was trawling speeds 850-1000 rpm’s so I doubt I got up to the high temps that are the fatal flaw.
Ours where done by Cummins in 2015 and in 2016 they where leaking at a price tag of $10,000 it’s ridiculous that Cummins cannot come up with a fix for this
One deisel shop I spoke to says he tells his customers to plan on every 4 years.
We wanted to have a new bridge enclosure made but now the $$ is being spent on repairs pisses me off.

also, had a broker walk the docks the other day and came back to our boat and asked if I was selling? He has 2 guys on LI looking for boats. He left his contact info
Hmmmmmm
 
I have approx 850hrs and I had very little signs of exhaust leaks. The manifolds where just a little bit warped according to the machine shop. The longer bolts where already installed. I am not sure if there was work done before I bought the boat or not as I didn't get good records with it.
 

Forum statistics

Threads
112,950
Messages
1,422,896
Members
60,933
Latest member
juliediane
Back
Top