Official Cummins 6cta 450C thread

[Forrestkk]

The piece of tube would heat faster than the block when putting heat on that area so the tube will actually get tighter in the hole. It is a significant interference fit so no matter how much heat was applied, it would make little difference.

Agreed.

I am not going to try this because it could crack the block, but warming up the block around the dipstick tube and the hitting the tube with an air duster upside down might break it loose. Kind of like the auto body guys who use dry ice and heat.

 

[ttmott]

Agreed.

I am not going to try this because it could crack the block, but warming up the block around the dipstick tube and the hitting the tube with an air duster upside down might break it loose. Kind of like the auto body guys who use dry ice and heat.

You could also clean up the broken end then drive it down into the oil pan with a correctly sized mandrel. Then pull it out with a magnet through the drain fitting.

 

[Forrestkk]

You could also clean up the broken end then drive it down into the oil pan with a correctly sized mandrel. Then pull it out with a magnet through the drain fitting.

Also a possibility, there is still just a tiny lip left at the block. As you mentioned, would need to Dremel that back. That just may beat the hacksaw.

Wonder if the block is tapered making it harder to push through than remove?

 

[ttmott]

Also a possibility, there is still just a tiny lip left at the block. As you mentioned, would need to Dremel that back. That just may beat the hacksaw.

Wonder if the block is tapered making it harder to push through than remove?

Definitely not tapered. You just need to make sure the length extending into the pan area will not bottom out before clearing the hole. The hole in the block is not deeper than the oil pan rail.

 

[Forrestkk]

Definitely not tapered. You just need to make sure the length extending into the pan area will not bottom out before clearing the hole. The hole in the block is not deeper than the oil pan rail.

That's easy, the length going into the block is just the knurled portion shown in my pic of the new tube. It's got all sorts of room to drop.

 

[Too Young]

Question: new to Diesel engines on the boat, why would there be a shut off valve on the return fuel line? And why would some one turn it off? Just took delivery of this boat and shame on me I didn’t notice that some had it off tucked clear up on top the fuel tank way up where you can barely see it. Boat ran great the first couple trips out. Until last night it split the rubber return line and made one heck of a mess in the bilge.

 

[Blown284]

Hi folks. Quick question. While running this weekend, I noticed that my port engine temp was approx 161 and starboard was 176. What would be causing that kind of delta between them? T-stat faulty? Both impellers just replaced.

 

[Forrestkk]

Hi folks. Quick question. While running this weekend, I noticed that my port engine temp was approx 161 and starboard was 176. What would be causing that kind of delta between them? T-stat faulty? Both impellers just replaced.

I had one stuck open tstat (there are 2 on each engine) on my port engine. Would run at temp under load, but cool off at idle. Both should come up to temp and hold solidly of they are working correctly.

There are also two temperature options, 160f and 180f. I currently have 160s in my port and 180s in my starboard so there is a delta. Going to switch to 160s on my starboard during annual maintenance.

 

[Blown284]

I had one stuck open tstat (there are 2 on each engine) on my port engine. Would run at temp under load, but cool off at idle. Both should come up to temp and hold solidly of they are working correctly.

There are also two temperature options, 160f and 180f. I currently have 160s in my port and 180s in my starboard so there is a delta. Going to switch to 160s on my starboard during annual maintenance.

Yep at idle, they are both stuck in/around 158 then once load hits, port will go to 161 and stay there... starboard goes up to around 176 max and stays there. I'm not terribly concerned just curious is all... fact is, it could have always been the delta between these two engines and I wouldn't have noticed it in the past.

 

[Forrestkk]

Yep at idle, they are both stuck in/around 158 then once load hits, port will go to 161 and stay there... starboard goes up to around 176 max and stays there. I'm not terribly concerned just curious is all... fact is, it could have always been the delta between these two engines and I wouldn't have noticed it in the past.

At idle mine come up to temp and just stay there regardless of thottle/load. Sounds like maybe one of the tstats is not closing fully.

 

[Blown284]

At idle mine come up to temp and just stay there regardless of thottle/load. Sounds like maybe one of the tstats is not closing fully.

Roger that. Thanks!

 

[saopm]

I’m looking to change my fuel filters on the engines. The manual says to prefill the filters. Assuming all goes well, no priming should be needed. If things don’t go well, is there bleed screw that needs to be opened when operating the primer plunger?

The manual shows the following, but this looks different than my 6CTAs.

 

[Forrestkk]

I’m looking to change my fuel filters on the engines. The manual says to prefill the filters. Assuming all goes well, no priming should be needed. If things don’t go well, is there bleed screw that needs to be opened when operating the primer plunger?

The manual shows the following, but this looks different than my 6CTAs.
View attachment 130654

I pre-filled with Sea Foam. Just a few pumps on and it was "squeaking" both engines fired right up with zero issue. Wouldn't sweat the bleeder.

 

[bbwhitejr]

I’m looking to change my fuel filters on the engines. The manual says to prefill the filters. Assuming all goes well, no priming should be needed. If things don’t go well, is there bleed screw that needs to be opened when operating the primer plunger?

The manual shows the following, but this looks different than my 6CTAs.
View attachment 130654

I have always prefilled with clean diesel and never needed the plunger. Prefill, install, and fire right up. Don't forget to open the valve on the tank if you close it.

Bennett

 

[Blown284]

At idle mine come up to temp and just stay there regardless of thottle/load. Sounds like maybe one of the tstats is not closing fully.

How difficult to change the Tstat? Know of a place where I can learn to replace myself and instructions or how-to?

 

[Jaybeaux]

Back in 2018 a buddy and I removed the After-coolers and heat exchangers to perform maintenance. While we were "there" we replaced the T-Stats as they were "wet" at the top where the hose comes off. Because we were removing the HX, we had to remove some coolant which we were able to reuse. I'm not sure if you have to do that when only changing T-stats. You do need to swing the alternator out of the way a bit to get to a bolt or two...again, memory. It helps to remove the serpentine belt. If you are mechanically inclined, it is really a staight forward procedure. I would check the SBMar site (www.sbmar.com) to see if there are any write ups or videos. Again, it was 4 years ago for me. Good luck.

Jaybeaux

 

[Forrestkk]

Back in 2018 a buddy and I removed the After-coolers and heat exchangers to perform maintenance. While we were "there" we replaced the T-Stats as they were "wet" at the top where the hose comes off. Because we were removing the HX, we had to remove some coolant which we were able to reuse. I'm not sure if you have to do that when only changing T-stats. You do need to swing the alternator out of the way a bit to get to a bolt or two...again, memory. It helps to remove the serpentine belt. If you are mechanically inclined, it is really a staight forward procedure. I would check the SBMar site (www.sbmar.com) to see if there are any write ups or videos. Again, it was 4 years ago for me. Good luck.

Jaybeaux

Replacing T-stats are pretty easy, unless a bolt gets stuck. I did it over the winter...probably would have taken 4 hours overall, but stuck bolt. Some images on this thread somewhere.

1. Drain coolant (petcock on oil heat exchanger and open expansion tank cap)

2. Remove belt guard

3. Remove belt

4. Remove hose that goes from top of t-stat housing to coolant heat exchanger and remove the hose neck

5. Remove belt tensioner and swing alternator over

6. Remove tstat housing

7. Clean everything up

8. Replace tstats, reassemble, refill

 

[Irie308]

Since the water that sits in the aftercoolers after shutdown settles at the bottom is the top zinc necessary? Also, I replaced transmission oil cooler and the old one did not have a spot for a zinc. The new one does. Is it worth installing one? Doesn't look like it would be an easy task either. Don't want to introduce a problem where there isn't one. Thinking broken zincs may due more damage from clogging than good.

 

[Blown284]

Replacing T-stats are pretty easy, unless a bolt gets stuck. I did it over the winter...probably would have taken 4 hours overall, but stuck bolt. Some images on this thread somewhere.

1. Drain coolant (petcock on oil heat exchanger and open expansion tank cap)

2. Remove belt guard

3. Remove belt

4. Remove hose that goes from top of t-stat housing to coolant heat exchanger and remove the hose neck

5. Remove belt tensioner and swing alternator over

6. Remove tstat housing

7. Clean everything up

8. Replace tstats, reassemble, refill

Thank you very much!

 

[Forrestkk]

Since the water that sits in the aftercoolers after shutdown settles at the bottom is the top zinc necessary? Also, I replaced transmission oil cooler and the old one did not have a spot for a zinc. The new one does. Is it worth installing one? Doesn't look like it would be an easy task either. Don't want to introduce a problem where there isn't one. Thinking broken zincs may due more damage from clogging than good.

FWIW, here is a shot of my zincs from annual maintenance.

Upper after cooler, lower after cooler, heat exchanger.

I installed freshwater rinse during last year's maintenance, so going to be interesting to see the difference.

My opinion is the more zincs the better. Any corrosion control is good.