Official Cummins 6cta 450C thread

Next question I have is regarding priming the fuel after fuel filter change. I don’t have a squeeze bulb. Is there a primer mounted on or around the fuel pump like I’ve seen on other diesels? I’ll try to hunt and search for one when I get back into the boat but thought I’d ask ahead of time. thanks

Yes, right on the fuel pump. Black plunger.

Here is a screen grab from this article on SBMAR. https://www.sbmar.com/articles/learning-your-cummins-marine-6cta-8-3-engine/

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I decided to scrape out the remaining foam from both air filter bases, wiped out the insides clean with mineral spirits soaked rags, re vacuum the insides of any left over crumbs of foam, and re installed. All the online information I found leads me to believe the foam is most likely for sound deadening of either turbo whine or air flow noise. I'm not really concerned with either noises.

I was under the impression that the foam/filter filtered out the residual oil from the exhaust keeping it from ending up in the turbo and eventually fouling out the turb.
 
I was under the impression that the foam/filter filtered out the residual oil from the exhaust keeping it from ending up in the turbo and eventually fouling out the turb.
Well let’s compare the sbmar enviro vent and the Walker. The sbmar just shoves the blowby gasses into the air intake through a connection at the end of the air filter. I don’t think the gases go through a filter. Just straight into the turbo. It also drains the blowby oil into a bottle (that eventually you have to empty). The Walker puts all the blowby into a closed system with built in filters that drains the blowby oil back into the oil sump and filters as much crap as it can out of the gasses with some filtering inside that closed compartment. The foam we are discussing is not part of this closed system. It’s in a tube passing the intake air to the turbo. It seems it really can only be there for noise. If I’ve got all that correct, then if you remove that foam I don’t see where you are any worse off than the sbmar envirovent.
 
Anyone here have a write-up on how you get to your starboard engine impeller and replace it? I'm assuming some boat yoga has to take place?
 
Anyone here have a write-up on how you get to your starboard engine impeller and replace it? I'm assuming some boat yoga has to take place?

Change your port first so you have the procedure, and then boat yoga. I used my selfie camera on my phone to get it all lined up.
 
Anyone here have a write-up on how you get to your starboard engine impeller and replace it? I'm assuming some boat yoga has to take place?
Best money you will ever spend since the impellers for this engine are keyed instead of splined.


Take an impeller with you to Fastenal or equivalent and buy a bolt that fits the threads. All you need to do is remove the plate. You can remove the impeller without takng the pump off of the engine. Make sure the key is at the 12 o'clock position. Bump the engine to get it there. 15 minute job.

Jaybeaux
 
Anyone here have a write-up on how you get to your starboard engine impeller and replace it? I'm assuming some boat yoga has to take place?
I followed a recommendation to remove the pump, then deal with the impeller. It was fairly easy to get the two bolts out and lay it forward of the motor (had to release the inlet hose from the tie-down). The face of the pump was up and the impeller easy to change. Cleaned up the face, added some permatex gasket maker, reinstalled the pump (two bolts). There is some twisting to get in front of the engine and access the pump bolts but I had it out in 5 min. Getting the key aligned was the hardest part (on both engines). I did just purchase the Impeller Replacement tool that Jaybeaux referenced - haven't used it yet, but expect it will make it even easier.
 
@Jay
Best money you will ever spend since the impellers for this engine are keyed instead of splined.


Take an impeller with you to Fastenal or equivalent and buy a bolt that fits the threads. All you need to do is remove the plate. You can remove the impeller without takng the pump off of the engine. Make sure the key is at the 12 o'clock position. Bump the engine to get it there. 15 minute job.

Jaybeaux

@Jaybeaux, can you key the impeller with the impeller tool in place? If so, buying one for sure!
 
If I understand your question, with the slot for the key on the shaft at the 12 o'clock position, I would place the key in the slot. Then take the installation tool with impeller inserted, with keyway at say 9 o'clock....reach around, get the tool started in the pump housing, turn until the key engages, and then pushit home. Then, a slight twist of the tool and then pull the tool out. DO NOT FORGET THE KEYWAY KEEPER! The little beige plasitc top hat looking thing!

I agree with Blueone that the zip tie method works. The first year I did mine, I did it that way, but it wasn't without a bit of frustration and Dawn dishsoap all over my hands!

Jaybeaux
 
Trying to confirm what model alternator I have so I can confirm cost to replace vs rebuild. From what I can see there is just 1 large wire and a small wire down below which I believe monitors the voltage? Question is what determines 1, 2 or 3 wire? Is it based in the terminals on the alternator?

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The terminals. It should be a Cummins part# 4003445.
You want a Delco Remy 22 SI 130 amp 3 wire. In our application only one of the wires on the two wire plug are used.

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The terminals. It should be a Cummins part# 4003445.
You want a Delco Remy 22 SI 130 amp 3 wire. In our application only one of the wires on the two wire plug are used.

View attachment 116423
Great...thank you! Also any up/downside to going with the higher amperage ones (145/160)? Assume it would be a faster charge at lower rpms if we go trawling speeds but would it be an even swap?
 
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The new style 24si is available at truck parts stores. Better alternator and was a direct replacement on my 480 CE
 
Planning to replace my alternator(s) soon. I'm also due to replace the coolant. I figured while I'm at it I'll change the thermostats. Having read through the thread I can't determine the best course of action in replacing the thermostats. Any advice as to access since I will already have the alternators off. Do I need to disassemble more for access?
 
Planning to replace my alternator(s) soon. I'm also due to replace the coolant. I figured while I'm at it I'll change the thermostats. Having read through the thread I can't determine the best course of action in replacing the thermostats. Any advice as to access since I will already have the alternators off. Do I need to disassemble more for access?
Not sure if it is this thread or not but somewhere on CSR I believe @Jaybeaux did an in depth write up on the T/stats and I think there may be 2 in each engine. Maybe he will chime in.
 
Can't seem to find an indepth write up but there is some info to be found at this link: http://clubsearay.com/index.php?threads/official-cummins-6cta-450c-thread.77886/page-12#post-1019780

We did remove an alternator on one engine but then fought a bolt going back on. But if you're changing alternators anyway, that's the way to go in my book.

Drain the coolant off of one of the lines from the coolant filter going back to the low point on the block. Remove the hose at the filter. If memory serves, you shouldn't have to drain too much just to replace the thermostats (yes, two per engine) but if you're changing anyway, then drain the whole thing.

I bought my T-stats from sbmar. They were the 160 Deg F versions. Kits came with gaskets, etc need for job.

If you have any questions, fire away.

Jaybeaux
 

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