Cummins 6BTA after cooler maintenence

BillD

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Yesterday I began the "fifth season" maintenance cycle on the Cummins 370s.
2012 completed the 4th season on the engines and they both have 515 hrs. +- each.
The after coolers were disassembled and reassembled with Alco MetaLube grease when new.
The 370s have been propped to 3100 WOT (with the boat heavy) since hour # 1 and I run 13 qts. in the oil pan.
Both engines have Seaboard Envirovent CC breathers.

Today I removed and disassembled the starboard after cooler.

Next step is degreasing and cleaning the core bundle and interior of the outer housing.

btw, as expected the end caps popped right off with a slight tap of a rubber mallet and the core bundle slid out of the housing with a light push of my fingers. It's important to take apart, clean and then grease back together.

More to follow.

FWIW, Bill D

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BillD

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I forgot to mention. Before I installed the new 370 RECONs back in 2009 I had the engines painted with one part epoxy paint.

I removed ALL the hoses for the paint job. When I put the hoses back on after the paint job I used Rectorseal #5 on all hose connections. Yesterday and today as I undid the hose clamps and pulled the hoses off ALL connections came apart easily with a heat gun applied to the hose.
Rectorseal #5 is good stuff to use. Doesn't dry out.

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BillD

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End caps O rings and zincs.
The cap with the melted zinc is the bottom cap. The bottom third of the after cooler is "always wet". Sits below the waterline on the Blackfin and I guessing most all DE boats.

You'll see that the cooling fins of the bundle are "oily".

The CC breather recirculates crankcase fumes through the engine air take and out the exhaust.

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Robert M

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Do you know if the 6cta is much different? Having a hard time getting a marine cummins guy lined up. I have a 16 yr old " step son" whos a motor head . Wish he would go to Marine diesel school.

For now Im gonna rip my aftercooler out next weekend myself .
 
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Robert M

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Take that back , a bit diff. going through manual . Hell I always got this site and if i get in troubler Its easier to drop it off then get someone to the boat.
Time to stop letting this diesel intimidate me , and start turning wrenches again. Its the only way to get to know the boat.
 

BillD

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Do you know if the 6cta is much different? Having a hard time getting a marine cummins guy lined up. I have a 16 yr old " step son" whos a motor head . Wish he would go to Marine diesel school.

For now Im gonna rip my aftercooler out next weekend myself .

Bob, no need for a motor head to take off an after cooler as long as you have decent access to the cooler.

The vast majority of DE's I've seen put together the "boat" is built around the "engine" with very tight clearances on the sides of the engine.

Here's some examples

One pic is a twin CAT install. Think about getting to any components on the center side of either engine.

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steveinak

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Now you got me thinking about cleaning my aftercooler and trans cooler !!! I'm pretty sure they have never been apart so where did you get the 2 sealer/grease you mention in your post. Like i don't have enough to do before spring :rolleyes:.
 

Robert M

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I can handle taking it off , I have never messed with one. Its stupid , becasue I wasnt intimidated to start turning wrenches on my old gasser. Maybe because most of those parts could be replaced at Napa same day. Time to get over my diesel phobia.

The good thing about having that engine box , and removable side panels is plenty of access.

Trying to push my stepson becasue , Gloucester only has a handful of independent marine Mechanics. A shit ton of guys that replace every part while diagnosing the problem if there even was one in the first place. Not that there arent a few good ones , but hard to get and you have to give blood .

Thanks for posting this walkthrough. guessing its helpful to many.
 
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Robert M

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Marine Nut,
Funny, I had that printed out on my desk . Although thankyou.
 

BillD

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Now you got me thinking about cleaning my aftercooler and trans cooler !!! I'm pretty sure they have never been apart so where did you get the 2 sealer/grease you mention in your post. Like i don't have enough to do before spring :rolleyes:.

Steve,

I use Rectorseal 5 (home depot any plumbing supply) for ALL hose/barb connections and as a thread sealant on all zincs, alarm switches, metal on metal or everything immersed in coolant or water.
Good sealant and doesn't dry out.

Alco MetaLube can be bought on the web.
Seaboard Marine sells it by the tube.

I think your JD coolers are fresh water cooled. I assume the core bundle still needs cleaning.
 

BillD

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Take that back , a bit diff. going through manual . Hell I always got this site and if i get in troubler Its easier to drop it off then get someone to the boat.
Time to stop letting this diesel intimidate me , and start turning wrenches again. Its the only way to get to know the boat.

Bob,

when you get the cooler off you can take the whole unit to Holt's in Saugus. He's the radiator/heat exchanger guy. Pretty sure he does after coolers too.

Of course you can do it yourself. Just make sure you get the CORRECT O rings for the particular cooler on your Cummins.
 

Robert M

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Bob,

when you get the cooler off you can take the whole unit to Holt's in Saugus. He's the radiator/heat exchanger guy. Pretty sure he does after coolers too.

Of course you can do it yourself. Just make sure you get the CORRECT O rings for the particular cooler on your Cummins.

Thanks Good to know if I get in trouble,
Im gonna give it a shot. My mentality up untill recently was, I can go to work doing what I do best ,and then pay the mechanic to do what he does best.
Although lately I want to get some skinned knuckles for knowledge . For this boat and the next seeing how i dont think ill be going back to gas . Atleast untill the moneys gone and I have go fishing in the zodiac.:-D
Sorry to hijack your thread.
 
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bestfish

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If the radiator shop won't do it, I boiled mine in a big pot over a turkey deep fryer. Used about a cup of powdered laundry soap and water. Boiled for about an hour. Came out great. And the gaskets are the same ones as a 2000 series racor.
 

bobv

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Took aftercooler off first time 2011 season at 2,500hours on 3126B cat. Lightly boiled in water with 2 cups borax and lightly ran a .22cal brass brush through bundle tubes. Wasn't that dirty to start but came out like new after.
 
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