[KevinS]

I realize that I missed one more sample taken for testing that was unintentionally omitted from my previous post at  https://www.sbmar.com/community/topic/losing-coolant-at-rest/#post-141077

After returning to my slip and the overflow bottle had risen with expansion coolant from the HX tank, I performed my usual protocol of fresh water flushing my engine and the next day after the overflow bottle expansion coolant went down, I pulled the aft anode from the HX for water sampling. Sent it out to HO Penn and no coolant detected in their analysis.

 

 

1 user thanked author for this post.

Andre Huizing

[KevinS]

As described, your recovery bottle is mounted within spec, but I prefer it mounted with the bottle mounted just below the top of the HX . This is an acceptable alternative and allows for the coolant level in the HX to be checked by removing the pressure cap. If it is mounted above, this cannot be done as the recovery bottle will drain back into the HX and overflow the filler neck when removing the pressure cap.  

 

To answer your question regarding my current expansion levels when running: the HX now accommodates all expansion and no coolant reaches the recovery bottle.

 

I’ve attached the Cummins mounting specs and a picture of where my recovery bottle is now located. The picture of my bottle is prior to letting it go empty. (I am using Cat ELC coolant)  

1 user thanked author for this post.

Andre Huizing

[KevinS]

Andre’ and All, I’m the guy that Rob was referring to in his prior posts who had chased the coolant loss ghost of my QSC 490. Seawater services are up to date the Seaboard way and I fresh water flush both my QSC and Northern Lights generator after every use.

When I purchased my boat  boat the coolant bottle was mounted on the bulkhead in front of the engine high above. Mounted incorrectly, it was useless, empty and not used. It sat empty and I would check the coolant through the fill on the HX. For seven years, the coolant always remained just above the bottom of the filler neck. 

 

In 2021 I was adding an inverter / charger and the layout for mounting put it in the location of the coolant expansion bottle. I thought this was a good time and opportunity to relocate the bottle to just below the HX and its filler neck as spec’d by Cummins so that it could perform and operate as intended. Immediately upon relocating the coolant bottle is when my coolant loss began.

   

My coolant loss was always took place at rest with the coolant bottle taking expansion coolant when hot and running. Then as it should and when the coolant temperature cooled, the expansion bottle would do its job returning coolant to the HX. It would always deplete a 1/2 inch or so at each cool cycle. After completing bilge and hose inspections while underway laying on both sides of the engine with hearing protection, again during and after cool down, pressure testing the HX hot and cold with no leak down, looking for bubbling in the coolant bottle while underway, visually checking the oil for creamy residue through the filler and checking the oil on the dipstick, having a coolant sample tested for saltwater, an oil sample tested for coolant, pulling the riser from the turbo to look for moisture and finally pulling the turbo for inspection, I came up empty handed and only able to scratch my head with lots of frustration.

 

After all of that, I finally listened to my local mechanic, who has his act together, that I call in for the heavy lifting things that I’m not comfortable with and to offer his sage advice. (Cummins, Cat and Lugger certified) He had been telling me of another local QSC of the same 2006 vintage having the same issue. That owner finally abandoned his expansion bottle letting it  go dry and the coolant settled roughly just above the bottom of the filler neck of the HX and stayed static just as mine was prior to relocating and utilizing the coolant bottle. I opted to do the same and my coolant has now also gone static roughly just above  the bottom of the HX coolant filler neck .. the same spot as his and the same spot where it rested before putting my coolant bottle into service.  Now being a bit paranoid and always looking over my shoulder with concern, I keep a marked dowel handy in a drawer and now check my coolant level before every startup through the HX filler neck and the cold coolant level hasn’t budged. It sits static, just above the bottom of the filler neck of the HX.

 

I don’t know the whys to all of this and where or how the coolant disappeared, but all that I do know is that my coolant loss has now stopped. Whether this will be your resolve, I do not know, but the steps that I had taken and the end result have me once again fully comfortable with coolant system on my QSC.

 

 

 

 

[KevinS]

Welcome to the marine QSC engine. To change the impeller the ECM must be removed. It’s a PITA, but in my opinion it’s a heck of a lot easier than removing  the pump. Just did mine .. it’s an every other year thing for me.

[KevinS]

All raw water coolers need servicing and should have their cores removed to be cleaned. ie; the heat exchanger and the aftercooler especially or you won’t be able to fully clean the airs side of the core.

It’s best and easiest to remove them and perform the services on the bench. 

Aftercooler: https://www.sbmar.com/articles/cummins-marine-aftercooler-maintenance/

[KevinS]

Here’s a better diagram. Petcock is forward of the bottom of the oil filter and aft and below the alternator. When I drain my QSC I just pull the black rubber coolant hose from above and drain it into pails, replacing the hose as pails fill and get swapped out. Off the top of my head be prepared for about 8 gallons.

2 users thanked author for this post.

Rob Schepis, John

[KevinS]

As Tony said, oil filter/HX side of the engine. Look below and aft of the alternator for the coolant petcock drain.

[KevinS]

Those pictures make it hard to tell if things are worse than they appear, but pictures 2 & 3 look pretty rough. The core shots look okay and should clean up. How about the end caps?

At $4,000 a pop or more by the time a new cooler gets to your door and you’re looking at two, I’d try to clean them up, put them back together with LOTS of grease and pressure test. Use a sanding block and sand the flat surfaces of the housing that mate with the end caps and gently hand sand the concave inside surfaces .. I’d continue into the housing as well then paint everything with black Rustoleum Painters Touch. That’s how I did mine, but did not appear to be as nearly corroded as your pictures show.
I cleaned my core ends with emery cloth.

[KevinS]

Glad that my poor man’s press worked for you. I still have the discs, but never expect the need to use them again.

Just as Tony .. I cannot access your link to photos.

[KevinS]

I made the switch last year. I just utilized the squeeze bulb primer and pushed fuel through the Double Double, into the new on engine filter and then through the remainder of the on engine fuel system until hearing a steady stream of diesel dropping back into the tank through the return line. Another dozen squeezes for good luck and the engine fired right up without even a hiccup.

[KevinS]

From my operating manual ..

1 user thanked author for this post.

Tony Athens

[KevinS]

Steve,

Follow this link and scroll down for a fully pictured description as how to set-up the Seaboard CCV system:

EnviroVent CCV Kit 6CTA 8.3 & QSL 9 Series

[KevinS]

sconrad208 wrote:

They are Cummins 6cta 8.3’s circa 2004 in a pursuit 38.

Okay, making sense now. You have the “480CE” which is the souped up air & fuel version of the 6CTA and not the QSC as you originally posted. The short answer is that your Walker Airsep does not have a coalescing filter.

[KevinS]

Charles Heldewier-Vignon wrote:

I have just sent you an email ,

Uncle bob 🙂

Charles .. please let us know how you make out with Uncle Bob at Gauge Saver .. thanks.

[KevinS]

sconrad208 wrote:

Here is the assembly that houses the coalescing filter that I am asking about…..it is completely sealed…….the removable portion of the air filter is not in the picture, but it is the standard 7.5” diameter x 9” long straight filter that attaches to this housing with 3 springs.

What you have pictured is not the unit that Walker shows on their website for the QSC engine, nor is the unit that I have on my QSC. The silencer lid is entirely different and the filter part number that you have listed does not fit the Walker QSC assembly. Something is amiss.

On the other hand and on Tony’s suggestion .. you may want to look into other options.

[KevinS]

Ditto what Tony stated. Be sure to get documented service history.

[KevinS]

Here’s the flyer for Fleetguard ES Complete .. good for “the life of the engine / 1,000,000 miles”. CAT says 12,000 hours and add additive at 6,000. Sounds to me like the same BS as doing the raw water service every 1,000 hours. I do give them a little credit for recommending coolant monitoring down in the fine print. For the cost of a couple of 5 gallon pails, I change the coolant out when the HX gets serviced.

Marine engines have too many other variables to just follow what’s printed on the jug or their brochures. Cummins, Caterpillar or any of the others never seem to really talk .. “marine” when they consider their recommendations and service intervals. Too me an an initial coolant baseline analysis and then annual analysis is just important as doing engine oil and gear oil analysis to see what’s really going on with your engine. In the scheme of maintaininh a boat having tese analysis done is cheap PM.

[KevinS]

Chart from Cummins Filtration

[KevinS]

Charles – Cummins recommends low silicate ASTM4985 (GM6038M specification) criteria.

Fully formulated coolaant must meet ASTM D-6210/D6211

They also recommend a 50/50 premix.

Because it’s easily available to me, I use CAT ELC (extended life coolant) which meets ASTM 6210

[KevinS]

Is this a new issue or ongoing?

Here are pictures of my WIF harness from QSC to Racor. It appears, but I am guessing, that the harness has some sort of resistor built in on the Racor side of the harness. These pictures might help you for comparison.

[Author]

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