600 HR Cummins Service

Kendall said:
Would fresh water flushwhen back at the dock reduce these service requirements? I see systems for sale that you hook up your water hose and flush the engine with fresh water when finished running for the day. I would happily do this to save $5000 every three years....

Does the corrosion happen most when running or when sitting? If sitting with fresh water in the coolers I would think the boat would have pretty much the service interval of a fresh water boat...

What do you guys think?
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I don't know about these costs that are floating around on this thread for the service of the coolers and exchangers. But my full service was less than $3000 including the cost of a new aftercooler. If I didn't need the new parts the job would have been well under $1000.
 
The $5K covers aftercoolers and heat exchanger service. So, having 3 yrs for one and 5 yrs for another helps a little to spread this amount in two separate stages.

Here are the price I got when I did the service in spring of 2011:

After cooler service - including R & R, cleaning, painting etc.
A - no new hoses 1400.00
B - all new hoses and clamps 1750.00

- these prices are for both after coolers combined
- hose condition needs to be determined at time of disassembly
- This assumes all cooler housings and cores are reusable

So, in conclusion you're looking at $1,400 every 3 yrs if your hoses and clamps are in good shape. Since I did the complete service to begin with, that's what I expect to pay for my next service of aftercoolers.

There are tons of debates on number of forums (especially boatdiesel) regarding flushing. I still have a good learning curve regarding diesels, but as of now my understanding is that any kind of flushing helps, but the affects are minimal and between not having enough volume (when flushing from citi water at the dock via garden hose) for the big engines and the effort to build convenient gizmo, majority don't feel it's worth it. Obviously, boating in fresh waters will most likely help you extend the service interval, but by how much is a big question.

When I discussed the subject with my cummins tech, he explained and showed me that recommended service is not just to ensure good circulation and having clean passages, but corrosion is the biggest factor. The problem is that if you ignore the service the aftercooler will be compromised where it won't be in serviceable state and you'll just have to buy a new one, which obviously is a lot of money. As you see from the breakdown Ive provided earlier, it's kind of a complicated process where the aftercooler gets completely cleaned, reconditioned and re-greased. So, when all is set and done it's as good as new.

"....Does the corrosion happen most when running or when sitting?..." - Others may deffer, but I'm a big believer that most of the "damage" takes place when boat is just sitting. this goes in line with my conversation while back with my tech regarding the genny. He simply said "you want it to live longer, just run it. They hate to just sit without use and will break more often if you don't run it".

ZZ13 said:
I don't know about these costs that are floating around on this thread for the service of the coolers and exchangers. But my full service was less than $3000 including the cost of a new aftercooler. If I didn't need the new parts the job would have been well under $1000.
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Obviously, the prices will be different based on the location, but the thing I love about my engines is that, despite the fact that they're in category of "big boys" the service is very much reasonable.
 
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I just did both my aftercoolers last weekend. Total cost was $75 (O-rings, cleaner, and paint). It did take time to remove, disassemble, reassemble, test, reinstall <6 hours total>. Port engine was a piece of cake, Strb more challanging.
 
Alex and LMBoat make good points. It all varies based on geography, who does the work, what specific steps were included, and how much of the work you do yourself. My service was pretty close to Alex's but not quite everything he got done. I did a little of the work myself but most was done by the mechanic.
 
Thought I'd show what a 12 year old aftercooler looks like that was never removed and cleaned. First picture is the bottom of the core. Second picture is the bottom of the housing.

photo2_zpsbc216614.jpg


photo1_zps9895830e.jpg
 
ZZ13 said:
Thought I'd show what a 12 year old aftercooler looks like that was never removed and cleaned. First picture is the bottom of the core. Second picture is the bottom of the housing.

photo2_zpsbc216614.jpg


photo1_zps9895830e.jpg
Click to expand...


I assume this is the core that you replaced new? What did the other side look like? Did you have any symptoms this was the case during the survey / sea trial?
 
Yes, this is the one I replaced. There were no symptoms (yet, fortunately). Oil samples were perfect. Performance was excellent. But this was a disaster waiting to happen. Soon, the seawater would have leaked into the air side and been sucked onto the engine. Due to reading on this site I knew to immediately service all the coolers as soon as I bought the boat, since I had no records of past servicing. Actually, I still would have pulled them and cleaned them even with documented maintenance records, as I wanted to set my own maintenance baseline.

By the way I also just had the valve lash adjusted (no records of that either). Most valves were "loose" (the mechanics term)
 
Forgot to answer the other question. The other side was just fine. It's the starboard side and can be taken off in just a few minutes as it's easily accessible. Our theory is maintenance had been done on it in the past but they gave up on removing the hard to get to port side.
 
Out of comparison, can you share some pics of the condition on the good side? Before and after cleaning if you have.


I've read a TON of posts on other sites, regarding the preventative interval recommendations on these after coolers. Seems consistent with every 2-3 years. I've also spoke with several mechanics that believe this is a tremendous waste of money!! Being half-a-handyman, I'm intrigued to take this on as a DIY project.

Thanks for sharing!!
 
I don't have pictures of the other side. My mechanic recommended the every 2-3 year pulling and cleaning. The problem came from condensation of moisture on the air side. I am just deducing here, but I suspect if you are in a low humidity climate and run your boat daily, I could see where condensation would never collect. But as a high humidity recreational boater, I plan to follow the mechanics recommendation.
 
Did the new aftercooler come with a condensate drain in the bottom of the housing?
 
ZZ13 said:
Thought I'd show what a 12 year old aftercooler looks like that was never removed and cleaned. First picture is the bottom of the core. Second picture is the bottom of the housing.

photo2_zpsbc216614.jpg


photo1_zps9895830e.jpg
Click to expand...

This is the very same thing I found with mine after I bought the boat. I had already sumwhat planned for this situation based on what I read before buying. Passed survey fine and ran great but would have killed the engine eventually. This is why I was so addamant about this and not trying to be a know it all. I believe most owners have no idea and don't service them properly, sell the boat to the next guy runs it for a few more years and loses a $20k engine or whatever a recon cost now. Glad to see you caught it before it was too late.
Also the only indication of bad aftercoolers is high blowby pressure. The saltwater that gets into intake air causes the cylinder walls to wear out of spec and blowby goes up but then the block is trash and needs a rebuild so it's no help. I love these engines and don't mind working on them as they are basic mechanical. They may smoke a little at startup and smell stronger than the electronic ones but they are great.
The aftercooler thing is not limited to just Cummins but all others brands too.

BTW I now have over 1,200hrs on mine. I am due for valve adjustment again. It was last done at 650hrs. Thanks for the reminder!
 
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PMC said:
Did the new aftercooler come with a condensate drain in the bottom of the housing?
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No. I did not get one of the new versions with that feature. It was an option, but I chose to buy a slightly used one that we also cleaned before we put it back on, to keep the purchase cost down. This one was taken off a boat with 50 hours where the owner had decided to replace its stock aftercoolers with the new version with the condensate drain.
 
I did my aftercoolers this weekend. Thought I would share a few photos. The boat is 10 years old, we purchased from original owner last August, always fresh water, only in the water 6 months per year, approx. 450 hours. Fairly straight forward to remove from the boat, of coarse on the 400 sedan bridge the port side is tight and takes a little longer than the starboard side. Both aftercoolers came apart easily, and had a minimal amount of condensate induced corrosion. Freshwater is very forgiving. Note the silt on top of the cores. The PO's marina was shallow and muck bottom. No harm, just kind of interesting the way it settles on top of the A/C's
DSC_0030_zpse36dbbcb.jpg
DSC_0035_zps02b083a3.jpg
DSC_0043_zps6ce213c9.jpg
DSC_0028_zpse4e29a77.jpg
 
I hope you guys are putting some type of grease when you reassemble the aftercoolers. I know the Cummins manuals don't specify that but makes things much easier to take apart next time and protect all the seals from pitting. Check out boatdiesel.com and search for aftercooler reassembly or something similar to that and a lot of information including photos will be come up on the search.
 
trit21 said:
I hope you guys are putting some type of grease when you reassemble the aftercoolers. I know the Cummins manuals don't specify that but makes things much easier to take apart next time and protect all the seals from pitting. Check out boatdiesel.com and search for aftercooler reassembly or something similar to that and a lot of information including photos will be come up on the search.
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Good point Tom, Yes , grease is the most important step, just no pics of it because it would take longer to wash the grease off my hands to take pictures than to assemble the thing. There was some discussion earlier in this thread about fresh water vs salt water on the a/c's, so I threw the pics and info up here as a comparison to some of the salt water pics from others. As you say, the how to of it is available elsewhere.
 
I think I know the answer to my question: What next?

I replaced both impellers, started up and got the same results. Port side had significantly more flow at idle and what I would describe as violence at 1000 RPM. Starboard side has much less flow and no violence at 1000 RPM, but more flow. Part of the violence on port side was the exhaust bubbling under the swim platform. None of that going on starboard side. The starboard side water pump had been replaced at some point because it is unpainted, all bronze.

The PO did aftercooler service in 2011:
http://clubsearay.com/showthread.php/47619-Official-Cummins-QSC-500-Thread?highlight=cooler
I don't have records of transmission or heat exchanger service.

What next? Call Cummins to do full intercooler and heat exchanger service? Can I just pull the intercooler core and clean it easy enough without pulling the intercooler off the engine? The starboard side is a ***** to work on.

Why such a difference between port and starboard? Both engines ran the same temps last season, never exceeding 176 at WOT. Why no exhaust bubbles under starboard at 1000 RPM?
 
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Frank answered a similar question recently and explained it has to do with the run of the exhaust lines inside the boat. So you may not have a problem. Hopefully someone remembers where he posted that (I don't).
 
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