Official Cummins 6cta 450C thread

Hi Bill,

I'm not a Cummins guy, but I am a member of Tony's BoatDiesel.com and I recall, when I was considering a 52 with QSMs, reading an article about reassembling the HE's with a generous amount of "Jet Lube" to help prevent that corrosion. I may be wrong on this as it was 3 years ago, but tony had a good article on the HE's disassembly and and cleaning...
Thanks Carter. I do follow his process and liberally (are you allowed to use that word on this site?) use the lube he recommends. Problem was that previous owner didn't. That's why I replaced one and am trying to squeeze as much life out of this one as possible.
 
Hi Bill,

I'm not a Cummins guy, but I am a member of Tony's BoatDiesel.com and I recall, when I was considering a 52 with QSMs, reading an article about reassembling the HE's with a generous amount of "Jet Lube" to help prevent that corrosion. I may be wrong on this as it was 3 years ago, but tony had a good article on the HE's disassembly and and cleaning...

As always, you are correct Carter. However, Tony had some sort of a fallout with the guys at boatdiesel so he no longer posts on that forum. He has his own forum on his website sbmar.com He has a page on the website called Tony's Tips and it covers just about everything you can think of in regards to engines and after coolers etc. Plus it has all the products he has available, and that is like a kid in a candy store looking at all the cool stuff to put on an engine.

Tons of great information on his sight, and customer service that is second to none. He is my go to for advice and anything I need to repair or replace on my Cummins 480's I really wish all marine service companies were as good as his.

Matt
 
I have two spare belts onboard. One came with the boat when I bought it and is Cummins part number 3911562. They other I recently bought and is the current part number 3288812. Best I could figure out the new part number supersedes the old part number. What I wanted to point out here is that the 3911562 belt is noticeably thicker than the new one. About 1/16".
 
Going thru the documentation we received with the boat and there is nothing on the engines. Have looked in the Cummins Quickserve site but it looks like you can only print a page at a time ... is there a pdf source for the manual(s)? I have seen some pay sites, but thought these manuals would be readily available.
 
Hello all. Being new to the diesel world, I am looking to see if anyone has a list of spare parts they carry on their boat for the diesels. In other words, I am wondering if someone has part numbers/names of parts etc. for things like filters, oil, belts..... My motors are 2004 Cummins CTA 480, model 6C8.3. Thanks to everyone in advance.
 
Hello all. Being new to the diesel world, I am looking to see if anyone has a list of spare parts they carry on their boat for the diesels. In other words, I am wondering if someone has part numbers/names of parts etc. for things like filters, oil, belts..... My motors are 2004 Cummins CTA 480, model 6C8.3. Thanks to everyone in advance.

You will find most or all the part numbers in the first post of this thread.

You will want to carry at least a set of belts, raw water impeller, and fuel filters for your engines and same for generator. You also need all the tools needed to replace those items which if you do you own maintenance you need anyway.

If your venturing far from services (like bahamas) you may want to consider other parts like alternators, water pump and possibly a turbo but those are expensive and take up room. They are also relatively easy to get shipped to us ports within a day or two if they aren't available at the port you need them in.
 
Add a set or two of zincs. They are cheap, and don't take up a lot of space. Two for the after-cooler, one for the heat exchanger. That's 3 per engine. Add 1 for the generator heat exchanger.
I also carry a gallon of coolant, a gallon or two of engine oil, and a quart of hydraulic fluid for the trim tabs. Miscellaneous electrical fuses, bits, etc. A 200 Amp fusible link for the bow thruster motor (Blue Sea Systems PN 5129 ANL Fuse 200 AMP). Swaterhouse covered the parts, my list is more fluids, etc for just in case scenarios.

Jaybeaux
 
Thank you Swaterhouse and Jaybeaux for the suggestions. I now remember page one of this forum listing the parts.....the mind ain't as sharp as it used to be!!
 
In addition to what has already been scribed above, I carry a full set of engine hoses. They are inexpensive, can be carried in a tub in the bilge and if any one currently installed blows, you have it. I also keep packing for just in case rudder or shaft leaks along with a spare battery powered bilge pump.
 
Great thread....how do you winterize these engines? New to 6CTA...old boat had Cats which were great. Boat is still in the water and need to get it pulled within the week.
Thanks,
Ed
 
Great thread....how do you winterize these engines? New to 6CTA...old boat had Cats which were great. Boat is still in the water and need to get it pulled within the week.
Thanks,
Ed

I never had those engines, but dont suspect the process is much different. This time of year, I follow these steps:

**in water**
Treat fuel
Boat ride, run engine warm (WOT RPM Test)
Drain oil using on board reverso pump (take samples for lab)
Replace oil filter (fleetguard)
Fill oil (valve cover pour - 5 gal)
Various inspections, wires, coolant, hoses, clamps, gasket leaks.....etc.
Fire engine briefly
Check oil level

**on land**
Close seacock
Drain (water lift) mufflers
Adapt fitting from 5 gal pail through strainer cap (fill with 5 gal pink)
Run engine (est. 20 seconds....until pail is empty)...listen for exhaust note to change as antifreeze makes it's way through
Remove aircep and plug turbo intake shut

I do the remaining (painting, zincs, coolant / fuel filters, etc. ) in the spring. If any gremlins say i need to work more, that's all is done after im back in the water.
 
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I never had those engines, but dont suspect the process it is much different. This time of year, I follow these steps:


**on land**
Close seacock
Drain (water lift) mufflers
Adapt fitting from 5 gal pail through strainer cap (fill with 5 gal pink)
Run engine (est. 20 seconds....until pail is empty)...listen for exhaust note to change as antifreeze makes it's way through
Remove aircep and plug turbo intake shut

Thanks…
How do you drain the water lift mufflers? How about the intercooler...drain it first? Do you plug the exhaust side too....rag in underwater exhaust and plug tell tale?
 
Thanks…
How do you drain the water lift mufflers? How about the intercooler...drain it first? Do you plug the exhaust side too....rag in underwater exhaust and plug tell tale?
There is a drain plug (7/16 head bolt) on the muffler.

I dont bother with draining the heat ex or intercoolers. Access to the zincs on opposite engines leaves bruises. 5 gallons seems to be enough to flush them out.

Plugging up the exhaust sounds like a good idea, but i have not done it. A few guys around the yard here do.
 
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One of my #6 above (on-engine instrument panel) is split in multiple places and probably is just shrinking up over 17 years. Anyone have any ideas other than forking out $80 for a new one? Nice steep price for a piece of rubber with a few holes in it.
 
Hello, my first post here! I'm buying a 2001 400 fly bridge with twin Cummins C450's. Getting it tomorrow actually. I have been reading a lot about these engines and already fell in love with them. I'm registered at BoatDiesel and sbmar. What are the speeds I should expect at different RPMs? Thank you.
 
Hello, my first post here! I'm buying a 2001 400 fly bridge with twin Cummins C450's. Getting it tomorrow actually. I have been reading a lot about these engines and already fell in love with them. I'm registered at BoatDiesel and sbmar. What are the speeds I should expect at different RPMs? Thank you.
At a minimum it should turn 2600 rpm on each engine at wide open throttle (WOT) with full fuel tanks and a clean bottom and clean running gear, but preferably 2650-2700. Speed is really an environment thing depending on currents and winds. But roughly 24-26 mph at 2200rpm and 31-33mph at WOT.

Do you know the pitch of the props? Factory set them at 24 pitch. That's based on a very light load (minimum fuel, water, gear). Many of us have dropped that pitch to 22.5-23 to account for a normal and full load.

Also lots of stuff pretty much runs end of life at the 15 year mark. Such as after coolers, turbos, transmission oil coolers, sea water pumps, shaft seals. Recommend you ask the age of all those items. If they haven't been replaced ever, the new owner will be doing that sooner than later. Same with house systems - fridges, a/c units, ice maker.
 
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Thank you for the fast reply! At sea trials it did about 20MPH at 2200RPM. empty tanks. They blamed it on dirty bottom. I dont know the prop pitch yet, will check asap. Thanks for the list of things to check at the 15 year mark. Will do... (OMG a lot! turbos too!) What are the signs that the after cooler core needs replacing instead of only cleaning?
 
Thank you for the fast reply! At sea trials it did about 20MPH at 2200RPM. empty tanks. They blamed it on dirty bottom. I dont know the prop pitch yet, will check asap. Thanks for the list of things to check at the 15 year mark. Will do... (OMG a lot! turbos too!) What are the signs that the after cooler core needs replacing instead of only cleaning?
If both turbos spool up at the same rate, that's a good sign you don't need to worry about them for a while. Plus they can be rebuilt.

Unfortunately the only way to really know on the after coolers is to take them apart. No seller will let you do that as part of the survey. That said, if it's a salt water boat and they have never been removed and cleaned then they are most likely shot and you would need new ones right away. In salt water they should be taken apart, cleaned and reassembled every 2-3 years. So see if the owner has ever done that.

That's not a very good speed for 2200 rpm unless you were going into a 5 knot current and a 20mph headwind. Generally the boat is hauled to survey they bottom (check running gear, test for water in hull, look for blisters). That should be done before the sea trial so the bottom can be cleaned at the same time. Then do the sea trial when you know you have a known bottom condition. Plus you can check the pitch stamp on the props. If it were me I'd tell them to get her cleaned and let's run it again.
 
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I just want to second Bill’s comments. You need 2650-2700 rpm for both engines at wide open throttle. I would suggest you make it contingent upon buying the boat if possible. 2200 isn’t even in the ballpark so you’ve got some issues.

Was there black smoke coming up on plane or at wot?
 
Thank you for your comments. Actually there were some circumstances including the owner is a friend of a friend, very good price, and the engines seem very clean (600 hours), that made me buy it without the full inspection (without hauling it out). I got a favorable dockside and engines inspection though. Skipper now admits that he did not push the throttle to the max at sea trial!!

Will do another test when the weather permits and check everything else and post the results here. Thank you for your help.

There was virtually no smoke during the trials.

If we disassemble the aftercoolers, what are the signs that the core needs replacing instead of just cleaning?
 

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