Official Cummins 6cta 450C thread

Fernando make sure to grease up the aftercoolers liberally with grease per Tony's instructions. I will be pulling and checking mine in the fall. It will be the two year mark. One is new four years ago and is still the old style with no condensation drain holes. The other is new two years ago and is the $3400 new style with the condensation drain holes.

Were the inside edges of your housings heavily pitted? Once the sharp edge corrodes away the o-ring won't seal it and a new housing will be needed.
 
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I removed my after coolers for maintenance, I took them to the radiator shop in Fort Lauderdale for cleaning and testing, the core was in bad shape I order 2 new cores, the aftercooler’s inside is a little pitted, the shop told me they can repair it, no need to change it.
MY QUESTION IS
This are the original after cooler, I notice they have a little hole at the bottom like 1mm or 2 mm, this little hole is all the way to the core, before I removed and run the engine I can feel the air blowing out, I believe this little holes ( they are in both aft coolers in the exact same location, at the bottom of the cooler)
Are this hole ( I believe they are for water condensation, I call them Condensation holes) are they original from the factory, or is something that the previous owner did?
See picture attached, does some one else here have the same Condensation holes?
I believe those little holes are made to allow to remove condensation water while the engines are running, or drip after the engine stops.
I am correct?
I saw the videos made by Tony at SBMAR about the coolers maintenance with Alco Metal lube blue greased, but it does not show this little condensation holes.
 
Those housings were not fabricated with those holes. Someone drilled them out. The new doubly expensive coolers have two removable plugs to drain condensation from the air side.

How is the shop repairing the housings?
 
ZZ13 said:
Those housings were not fabricated with those holes. Someone drilled them out. The new doubly expensive coolers have two removable plugs to drain condensation from the air side.

How is the shop repairing the housings?
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They told me with Aluminum Epoxi and over size O-ring, it is just a little bit pitted on the inside, this is a very reputable marine radiator shop very well recomended, I suppose they know what they are doing.
Broward Radiator Shop.
 
FeLizDream said:
They told me with Aluminum Epoxi and over size O-ring, it is just a little bit pitted on the inside, this is a very reputable marine radiator shop very well recomended, I suppose they know what they are doing.
Broward Radiator Shop.
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A little pitting on the inside surface is ok. The grease will help prevent that in the future. But you don't want any defects in the sharp edge that forms the circle. Then the o-ring may not seal.

If you can post pictures of before and after of the end showing the edge.
 
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Also. I recommend you use the o rings on Sbmar.com and not the factory Cummins ones. They are a bit thicker.
 
ZZ13 said:
Has anyone adjusted their fuel aneroid? Since I've owned it, one of my engines has had a slight delay (a few seconds) spooling up the turbo and after eliminating everything else (air restriction, exhaust leak, etc) I'd like to see if adjusting the aneroid will make a difference. Here is a link to pictures of it: http://www.sbmar.com/articles/aneroid-adjustment-on-the-bosch-p7100-injection-pump/
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I know it is an old thread, but I had to adjust my aneroid on the starboard engine because of delay coming up to speed. This was a few years ago, it fixed the problem and never had an issue since. You need a special Torx tool to get to the adjustment dial.
 
ZZ13 said:
I made up a maintenance schedule with part numbers and sources. I'll be glad to send it to you if you pm me your email. Sorry but it includes a Westerbeke generator rather than an Onan.
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I know I am jumping in here. Would you mind sharing this schedule? Thanks in advance (BTW-can't figure out how to PM anyone).
 
20180704_105851.jpg 20180704_105855.jpg 20180704_113145.jpg 20180704_113150.jpg Happy Independence Day!
I have a question about operating temperatures and a slow change that I've been watching.

Background: 2004 420, 6CTA 8.3. 850 hours, we boat in the upper reaches of the Potomac River with some jaunts down river to some saltier water. We purchased this boat in August of 2016 and as a condition of sale, we had the entire raw water train serviced. The boat had 705 hours on them at sale. A good thing too as the Port aftercooler was not serviceable. It was fused to the housing. New Port side aftercooler, and the Starboard side was removed, cleaned, greased, etc. Heat Exchangers were cleaned. New waterpumps & impellers (Stbd 5/16, Port 5/17). In 2017, the engines ran at a needle width above 160 degrees on the gauges.

This season, I began noticing that the temps were just a touch higher. "A touch" is a technical term, but still a discernable increase. Today, they seemed a bit higher yet. Now, the weather, it was almost 100 degrees in the Washington DC area today. I cruise at 2200 rpm, boat is lightly loaded, no vibrations in the drive-train.....Here are the numbers. My concern is the starboard motor at cruise speed.

Idle 2200 rpm
Port 160 168
Stbd 160 175

I'm attaching four (4) pictures: 2-Port and 2-Stbd. At speed and at idle. You can differentiate between the to sides by which way the temp needle points: To the left=Port, to the right=Stbd. Before our outing today, I cleaned all strainers and even used my shop-vac to blow air back thru the seacocks and thru-hulls as the grass is making an appearance.

Sorry for the long post. We are supposed to take her on a 100+ mile trip at the beginning of August, so if there is anything to be done, now is the time.

Thanks for your help,

Jaybeaux
 
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Jaybeaux

For reference I have a 2001 460 with 6cta’s and boat in coastal Texas where it is 100 degrees most days and the water temp is 90+.

You say you serviced the aftercoolers/heat exchangers 26 months ago. I think it’s time they get serviced again. 2 years is reasonable time to perform this service. I personally follow Tony Athens advice on Sbmar.com.

My engine temps are 170 or below even with the extreme heat and high water temp so I do think you have some restriction in the systems but you’re not at a dangerous point just yet. Also the gauges on our boats are not known as the most accurate so I would look at the on engine panel and take your data from there.

Hopefully that helps!

Josh
 
Josh, thanks for the words. That's what I'm leaning towards. You just confirmed my suspicion. Now my next question/dilemma is should I do the gear oil coolers while I'm having the aftercoolers serviced? I believe that they are original. And I suspect that the answer should be "hell yes".

Thanks again.

Jaybeaux
 
Well my answer is yes. Simply because it’s right behind the aftercooler so why not pull it while you are in there. I can’t stress enough how you should flow Tony Athens procedure on a sbmar.com. His methods are proven.

Also make sure you don’t have impeller pieces in the cooling circuit. I see this often and it amazes me people don’t take the time to fish these out.
 
Ok, here is going to be my plan of attack. I am going to apply Occam's Razor, the Law of Parsimony!...the simplest solution tends to be the right one.

Having cleaned the strainers and the thru-hull yesterday, I know that they are clear. I am going to remove the starboard raw water pump impeller and check it's condition. It is right about 2 years old with 150 hours on it. It may be in need of a change. I am "hoping" that I find a partially shredded impeller and then I have to go find some bits at the bottom inlet to the aftercooler. I would consider this a major WIN!

Naturally this is the starboard engine where the water pump and aftercooler are located on the outboard side of the engine. Any advice on which way to approach: over the top of the engine laying on a big moving blanket or laying across the starboard exhaust tube and working in a prone position?

Jaybeaux
 
I can crawl around the outside of mine. I’ve found it’s easier to take the pump off and service it outside the boat then reinstall the pump but every boat is different.

While I think you should change impellers, you need to service the aftercoolers as well. If you haven’t read much about Cummins this is a known issue. They must be serviced every 2 years or they will corrode together and you will start the process of decay. I highly recommend taking them off completely and doing a proper service and closely following Tony Athens advice. He is not some couch engineer, he repairs Cummins all day every day and is an authority.

The cooling system on Cummins engines requires the raw water side be serviced but don’t ignore the coolant side either. It requires testing the sca levels and adjusting the additive package with filters. If you choose to ignore all of this it can be bad so that’s why I just advise of doing a complete service all at once

Aftercoolers, heat exchangers, gear coolers, thermostats, coolant flush, coolant filter.
 
I agree with you about servicing the aftercoolers. My 2 years is up in mid-August of this year. The mechanics around here say you can go 3 years. My plan was to have them serviced over the winter. I also monitor my coolant chemistry, utilizing the test strips. I don't have the bottle here with grid on how your coolant is doing, but I know that my freeze protection is -30 Deg F, and the Molybdate reading is on Row #4 and the Nitrate Reading is on Column F. It put me all in the green areas.

I fully follow what you are telling me about aftercooler maintenance. I've spent many hours on Tony's site. Good source of information.
 
Just a heads up... on Friday I could not start one of the engines at the gas dock. The Port engine has been progressively getting slower to crank. I figured it was a battery going bad. It did start fine to get to the gas dock but after refueling I just got a click. I ended up getting the local mechanic to look at it and he said I needed a new starter and batteries. I ended up calling Cummins who came out to look at it and said it was the Aux mag switch just below the starter. Sure enough he replaced it and the engine started right up... no starter or battery issues what so ever. Cummins said that was his fifth switch replacement this season.

Aux Mag Switch.jpg
 
Blueone said:
Just a heads up... on Friday I could not start one of the engines at the gas dock. The Port engine has been progressively getting slower to crank. I figured it was a battery going bad. It did start fine to get to the gas dock but after refueling I just got a click. I ended up getting the local mechanic to look at it and he said I needed a new starter and batteries. I ended up calling Cummins who came out to look at it and said it was the Aux mag switch just below the starter. Sure enough he replaced it and the engine started right up... no starter or battery issues what so ever. Cummins said that was his fifth switch replacement this season.

View attachment 57604
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I carry a couple spares. The previous owner of my boat replaced a couple and I've replaced one already. In my case all on the port engine.
 
Woody said:
I carry a couple spares. The previous owner of my boat replaced a couple and I've replaced one already. In my case all on the port engine.
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Mine too.... It couldn't be in a tougher spot on that port engine
 
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