cummins 6cta 8.3 430?

Robert M

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Now that i have decided that a new build is out of my relm for a few years, I have decided to keep the boat I own. Hell I should be more then just thankful I have her in the first place.
Like any boat that is 10 yrs old Im starting the checklist of odds and end repairs for the spring. Little projects that my ocd wont let go.
F'n wish I had I yard big enough for a tent enclosure , and the boat. I am fighting the urge to start my projects, hell im keeping myself up at night.
Anyways, after running into one of the marina's workers who seemes to like the boat. I was asked the hours on my cummins. After telling him it had a very well matained 775 hrs on it , he replied still have another 700hrs of life left on her.
I was baffled, I know everyone on this forrum has there prefrence in power, but what is the average expected life span of a cummins 6cta that is matained correctly, or beyond. One that is lightly used lets say 100 hrs a year.
I know this a hypothetical question. Thoughts?
 

CEShawn

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The boat I bought has 5555 hours on it, 2007 RECON 6CTA. I have no fear that the engine will last atleast another 2,000 hours or so. The biggest thing is to follow people on BOATDIESEL.COM about how to extend the life of it. Its not just about oil changes, but heat exchangers service, etc. Boat diesel is a lifesaver and learned alot from them. View Tony Athen's article's at Seaboard Marine - Custom Marine Diesel Repower Specialists as well.

I know some people who have 8000-12000 hours on this engine still. You never know though. I had a brand new Cat 3406E that failed at 750 hours as the oil pump failed, wiped everything. I bought that brand new off the floor and was in two years.
 

CEShawn

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My thing has also been to collect as much data as you can on your engine, get a pyrometer, boost pressure, I also want to upgrade my filtration system as well as have mechanical gauges, probably because I am anal and/or a marine engineer by trade. Just installed my Murphy gauges last weekend.

Make sure you are doing some sort of oil analysis as well, religiously to trend what is going on.
 

captainlarry84

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I you keep all PMs up especially the cooling system and never over heat or over wheel the motor. I would est the major engine components @ 6,000 hours.
 

CEShawn

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Oops, I meant to say another 2,000 hours before I do some top end work, or maybe Larry is right at 6,000, then again maybe next time I start it... Its like powerball, but the opposite effect!
 

Robert M

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So this kid didnt have a clue he tried telling me they built those blocks out so much they blow often. Im having the cooling system gone through again before its launched in spring due to Bill D's posts. ;)
 

CEShawn

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Not to be picky, but watch out the lightly used comment... lightly used with the engine dialed in with RPM, service, etc is fine, lightly used INCORRECTLY is very dangerous.
 

Robert M

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I know You can't beet murphy's law. I just figured 4000hrs as a number, good to hear . I get people who know my boat who say" wow would of been nice if it was a b not a c ",. What the hell does that mean?
 

Robert M

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What I meant is im not a commercial fisherman, pretty sure after talking to the guy at h&h prop today that the boat is dialed in. I may need to bring the prop down a bit ,but I wanted to take a few small dings out, and the layer of paint some idiot put on it off first.
 

djmarchand

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Robert:

Engine life all depends on how you run it and how you maintain it. The best maintenance in the world won't compensate for running the engine on the pins all day long. If you do that, the yard guy may be right.

But if you maintain it well, make sure that it is propped to reach rated rpms at wot and run it at no more than 3-400 rpm off of top (except for a few minutes to check wot rpm) then it will last many thousands of hours.

David
 

Robert M

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Robert:

Engine life all depends on how you run it and how you maintain it. The best maintenance in the world won't compensate for running the engine on the pins all day long. If you do that, the yard guy may be right.

But if you maintain it well, make sure that it is propped to reach rated rpms at wot and run it at no more than 3-400 rpm off of top (except for a few minutes to check wot rpm) then it will last many thousands of hours.

David
Thanks yall, I run my boat at aroun 1900-2000 at 20k wot is 2500 or so . my motor is rated at 2600 under load. Im thinking the prop ding might be the issue, along with some unwanted paint . I was told motor should rev out 10% higher in neutral, which it does no problem . Hits 2800 and change , not something I do regulary but I did check it.

Does this sound right?
 
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petrel

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I bought a boat from a guy who managed to ruin a B series in less than 2000 hours, most likely because of exhaust issues. That was a 315 hp version. I should have had it checked out before I bought it. Live and learn.
 

Robert M

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why c series over b cummins? Where's Bill D when you need him?Why would someone rather a b ? aw F*&K i give up
 

traditions

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C series has liners,b has to be bored and sleeved.The c series is a great engine.The only bad thing I ever heard was some of the early ones failed because of condensation in the after coolers would get moisture on the pistons on #6.The newer ones have a drain in the after cooler I believe.I know of some 210 b's with 18000 hours and going strong,great engine. Diesels are made to be run,the absolute worst thing is to let them idle.When a new diesel is broken in it should be started up and checked out and brought up to 1200 rpm to warm up and then run to break in the rings to the cylinders.If they idle the rings gum up and glaze the cylinders,causing blow by.The correct way to break them in is with good pressure on the rings.If they wore out in 1400 hours most commercial boats would be repowering every year.That 430 C is good for 12000 no problem,run her till she tired and rebuild and it is just as good as new.You cant beat a mechanical for dependability.
 

Robert M

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C series has liners,b has to be bored and sleeved.The c series is a great engine.The only bad thing I ever heard was some of the early ones failed because of condensation in the after coolers would get moisture on the pistons on #6.The newer ones have a drain in the after cooler I believe.I know of some 210 b's with 18000 hours and going strong,great engine. Diesels are made to be run,the absolute worst thing is to let them idle.When a new diesel is broken in it should be started up and checked out and brought up to 1200 rpm to warm up and then run to break in the rings to the cylinders.If they idle the rings gum up and glaze the cylinders,causing blow by.The correct way to break them in is with good pressure on the rings.If they wore out in 1400 hours most commercial boats would be repowering every year.That 430 C is good for 12000 no problem,run her till she tired and rebuild and it is just as good as new.You cant beat a mechanical for dependability.

Thats what I thought, I dont run my boat on idle much because I just fire up the generator if im anchor for the day, plus the 6 batts in my boat can run alll that I need four many hours. I just am getting some crazy info lately. I do plan on checking out the after coolers. Love my single diesel downeaster. This site has been great. I know I made the right call, but just wish I knew more. The twin merc 350's in my last boat almost bankrupted me , but at least I did know more about them. I guess we live and learn , and the trick is to learn faster then live!
 
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badabing

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FYI this 8.3 liter you are pulling 430 out of is the same block as the qsc 8.3 that they get like 580 hp out of......my buddy had the 8.3 diamond in his 31 BHM with a 2to1 gear and a 28 square ( i think) and he had 6000 hours before he sold it and im sure the new owner has gone over 10000.......
 

Robert M

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Thats why I like this site. Im ignorante, but seek knowledge. The info around the doc doesnt seem correct , even to a dumb tile guy. Is there any info on my prop- rpm question?
 

Robert M

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Thats what I thought, I dont run my boat on idle much because I just fire up the generator if im anchor for the day, plus the 6 batts in my boat can run alll that I need four many hours. I just am getting some crazy info lately. I do plan on checking out the after coolers. Love my single diesel downeaster. This site has been great. I know I made the right call, but just wish I knew more. The twin merc 350's in my last boat almost bankrupted me , but at least I did know more about them. I guess we live and learn , and the trick is to learn faster then live!

So why would some dude who saw my boat on this site come up to me and say" don't understand why the previous owner didn't put a b serious in that boat", ? From the research I did , the c series was a better choice. From what I understand Stacey ( genral marine) talked the previous owner into upgrading into the c and more hp.
 
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BillD

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Now that i have decided that a new build is out of my relm for a few years, I have decided to keep the boat I own. Hell I should be more then just thankful I have her in the first place.
Like any boat that is 10 yrs old Im starting the checklist of odds and end repairs for the spring. Little projects that my ocd wont let go.
F'n wish I had I yard big enough for a tent enclosure , and the boat. I am fighting the urge to start my projects, hell im keeping myself up at night.
Anyways, after running into one of the marina's workers who seemes to like the boat. I was asked the hours on my cummins. After telling him it had a very well matained 775 hrs on it , he replied still have another 700hrs of life left on her.
I was baffled, I know everyone on this forrum has there prefrence in power, but what is the average expected life span of a cummins 6cta that is matained correctly, or beyond. One that is lightly used lets say 100 hrs a year.
I know this a hypothetical question. Thoughts?

So this kid didnt have a clue he tried telling me they built those blocks out so much they blow often. Im having the cooling system gone through again before its launched in spring due to Bill D's posts. ;)

Not to be picky, but watch out the lightly used comment... lightly used with the engine dialed in with RPM, service, etc is fine, lightly used INCORRECTLY is very dangerous.

I know You can't beet murphy's law. I just figured 4000hrs as a number, good to hear . I get people who know my boat who say" wow would of been nice if it was a b not a c ",. What the hell does that mean?

What I meant is im not a commercial fisherman, pretty sure after talking to the guy at h&h prop today that the boat is dialed in. I may need to bring the prop down a bit ,but I wanted to take a few small dings out, and the layer of paint some idiot put on it off first.

Bob, you are correct, the kid doesn't have a clue. I'll bet the 6CTA will be running just fine LONG after you've sold the boat and moved on to your next one! The base engine will last many many thousands of hours. It's the bolted on stuff that fail over time mostly due to marine age.

IF, you:
1. keep the engine propped to an accurate 2650-2700 WOT with the boat as heavy as you'll ever run her. (meaning under propped a whisker)
2. Service the after cooler and salt water side of the cooling system every 4 years no matter how many or less hours. (corrosion of dissimilar metals and salt water mist into the combustion)
3. The exhaust system is designed to NEVER allow salt water to back into the exhaust manifold through the turbo. (#6 cly. gets the water 1st then kaboom)
4. Alarm the engine for "loss of raw water" and an extra alarm switch or two for high temp engine coolant. (overheats cause long term nit pickin issues)
5. Clean #2 diesel with NO water ever (injectors)
6. Use Fleetguard filters, change the oil & filter every 100-150 hours
7. keep the engine/room salt water free (no rust)

8,9,10, there's probably a few more :D, but the ones above are the biggees.
 

Robert M

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why would I want to over prop the boat to run higher then the recomended rpms? Its ratted to run at 2600?
oh guru of cummins ;) I just bowed by the way
 
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