New owner of a 38 Bertram Convertible with 6CTA 480ce's – immediate priorities?

[Nicholas]

Just closed on a B38 powered by 2002 6CTA’s with about 1500 hours. This is my first diesel boat so I’ve spent the last month or two pouring over this site and some others to get educated.

In 2016 the engines had heads rebuilt, turbos rebuilt, aftercoolers and heat exchangers serviced, and new injectors installed. One engine also had a piston, liner, rings, and bearings replaced and the other got a new belt tensioner and serpentine belt and had the exhaust pipe from the turbo to rubber boot rebuilt (not sure what happened there).

One engine blew a raw water hose during the sea trial, then in the second sea trial the other engine wouldn’t climb above 1900 RPM. However after the secondary fuel filters were changed the engines spun right up to just over 2600 and ran like a dream for several minutes with no issues.

My plan of attack is to change the motor and gear oil, change the zincs, racors, add a freshwater flush system, and replace any other hoses that look worn. Since the heat exchangers and coolers were done about 100 hours ago in 2016, i figured i could wait a year on doing those. I’m also going to go ahead and have about 100 RPM worth of pitch taken out of the prop. After all of the reading on this forum and others on the dangers of overloading these engines, and based on the fact that they seemed to have required a pretty major overhaul at 1400 hours, it seems to me like a prudent thing to do.

Is this logic reasonably sound? Anything else I should do right-away? Since he only did one of the belts should I go ahead and do the other? Thanks and I look forward to being a part of the community!

Topic

[Philip]

Also noted on your old cooler cores the silicone strips are still there. They are a PITA to reinstall and most leave them out so I wonder how the coolers were serviced in the past?

Phil

[Nicholas]

Rob Schepis wrote:

That is a fast turnaround time – I hope they remembered to pull them apart and grease them!

lol me too. but i figured maybe they do it when they get them in so they are sitting on the shelf ready to go.

[Rob Schepis]

That is a fast turnaround time – I hope they remembered to pull them apart and grease them!

You see those flattened tube ends – looks like zinc maintenance was not up to snuff, that’s from broken off (or backed off) zinc being bounced in the sea water flow like a lost sock in the laundry….

[Nicholas]

…placed the order for new coolers this morning and got a notice that you guys had shipped them by 08:40am west coast time – now that’s a fast turnaround! appreciate it.

[Nicholas]

you guys called it

Well, you guys called it. I got the aftercoolers disassembled this week and they are pretty much shot, despite the fact that the PO had documentation of them being serviced, including “acid soaked and rodded out” in 2016, and despite the fact that both the engine surveyor and a second engine mechanic down in FL I had look at them told me they were “pristine.”

The tech i have working on them now thought perhaps the houses could be reworked (honed and epoxy coated) and we could roll the dice on having the cores cleaned and pressure tested but he thought they were bad enough that just replacing both assemblies and starting fresh was the better option.

The only good news is that thanks to this forum and the articles on this site I knew to make the coolers a priority regardless of what I had been told by the PO and surveyors and (hopefully) got them off before any damage was done to the rest of the engine.

I guess you can add me to the (long) list of people who have learned the hard way to always assume the aftercoolers need to be replaced on ANY used 6CTA engine regardless of what the PO says and even shows you in terms of maintenance receipts!

Attached are a couple of pictures of the cores. Yes, that is a zinc embedded in the cooling channels of the core! My technician said he found 2 or 3 zincs broken off in each cooler. He said the caps were sealed with permatex that had been painted over to make it harder to tell it was a hack job. UGH!!!

[Rob Schepis]

Yes the aftercoolers need to be serviced either by you or under your direct watch… they are always the achilles heel of the sea water side…even Cummins can’t get them right as supplied new..

[Nicholas]

Rob Schepis wrote:

I know we covered this already as to propping 480 vs 450 but here’s you performance specs including GPH. She may be a tad thirstier than you think especially if she’s propped as a 480CE and propped on the edge, or worse…

How exactly did the tech determine the aftercoolers were pristine? What was actually disassembled and inspected?

Next leg of the trip I’ll be able to get gph and engine load data at various RPM settings and will post them here. I have suspected all along it may be overpropped at least slightly. But I’ll know for sure when I finally get data.

Re:aftercoolers, he said he looked in them but he definitely did not remove them and disassemble them. I assumed he removed the caps to inspect inside the cooling channels. I know he removed the hoses because he replaced one. They are coming off later this year no matter what for a full servicing. But I’d much prefer to wait on everything I can until I get the boat up to me instead of hiring people to work on it when it’s 800 miles away. Makes it really hard to keep people accountable (which I’ve already learned the hard way a couple of times over).

[Tony Athens]

Rob,

Good question on the aftercoolers although we both know the answer–It’s 100% impossible to determine the condition of the aftercooler as to the “parts that matter” without a full disassembly…………”Love those mechanics”..

Tony

[Rob Schepis]

Good post, great photos. Fine looking boat. Good to see the windlass is stored “at rest”… too many times guys leave them TIGHT to keep the anchor secure and that is damaging to the bearings and shaft.

I know we covered this already as to propping 480 vs 450 but here’s you performance specs including GPH. She may be a tad thirstier than you think especially if she’s propped as a 480CE and propped on the edge, or worse…

How exactly did the tech determine the aftercoolers were pristine? What was actually disassembled and inspected?

[Nicholas]

Update

Just wanted to revisit this thread and provide an update on progress so far. Over Christmas break we took a trip from Indian Harbour Beach down to Palm Beach. It was a great little shakedown cruise and the boat and engines performed great. I noticed though that the voltage was low on both engines. When I got it back to Brevard I had the alternators removed and tested and one was shot and the other wasn’t far behind so I had those rebuilt and new batteries put in.

I also had the aftercoolers inspected and the technician said they looked “pristine” and did not recommend servicing them yet. I’ll wait until I get the boat up to where I live and can remove them myself and take them in to be serviced probably next fall. He also said the turbos looked fine.

I’m still concerned about the exhaust set up and he agreed that it isn’t ideal and in certain sea conditions and certainly backing down a fish, water could get into the turbo. He thought it would be difficult or impossible to add any more rise given the engine room restrictions but he suggested adding surge tubes to mitigate the risk. So that’s another one for my longer term to-do list.

I finally got the J1708 engine gateways and got them installed this weekend and now can view the engine data on my garmin MFD’s via NMEA 2000.

I have not had a chance to plot the fuel burn vs. RPM curve but I suspect I may be over propped. I’ve started moving the boat from Florida up the East Coast a weekend at a time, and I think my fuel burn is higher than it should be. I did Indian Harbour Beach to Jacksonville the weekend before last but it was hard to calculate fuel burn because there was lots of stopping and starting in the ICW. However, last weekend I did Jacksonville to Charleston, which is about 180NM, and I think I burned 319 gallons of diesel. I was cruising offshore in mild conditions and following seas at about 2350 RPM, which is about 26.5 kts. Burning 319 gallons in the 7-7 1/2 hour trip would mean I was burning over 20 gph per engine, which is way too high for 2350 RPM. I’m hoping that maybe I didn’t top the tank all the way off when I filled up in Jacksonville and I actually burned less than that. But since I now can read the fuel burn data off my displays, I should have better data when I make the next leg of the trip up to North Carolina.

Only other problems I’ve had is a tiny bit of white smoke at both idle and cruise on the STBD engine (I have another thread about that – i’m optimistic that it’s not a sign of anything major) and the port engine has stalled out twice at idle (over ~50 hours of running the boat). I need to check to make sure I have the correct ECM firmware version to address the stall/stumble problem detailed on this site.

I’ve attached a few photos of the journey so far. Thanks again for all the tips and advice and wisdom… more updates to follow.

[Rob Schepis]

You could go back with ultra copper high temp RTV or purchase a gasket. The graphite gaskets are the most forgiving if the surfaces are not 100%..

https://www.sbmar.com/product-category/gaskets-o-rings/turbo-gaskets-hardware/

[Nicholas]

If i’m going to pull the elbow off the turbo do I need to order a new gasket? The process of just pulling the elbow off to look in the turbo likely necessitate replacing gasket (between the turbo outlet and elbow)?

[Nicholas]

Rob Schepis wrote:

For sure. And as to your turbo question, if I understand it right – you just need to remove the elbow from the turbo outlet, no turbo disassembly..

That’s what I suspected. I’ll report back in a few weeks when I get back down to the boat.

[Rob Schepis]

Nicholas Cummings wrote:

Thanks i had my eyes on those. Seems like a very inexpensive but helpful mod.

For sure. And as to your turbo question, if I understand it right – you just need to remove the elbow from the turbo outlet, no turbo disassembly..

[Nicholas]

Thanks i had my eyes on those. Seems like a very inexpensive but helpful mod.

[Rob Schepis]

Those pressure gauges are gear pressure.

As to your low voltage issue, check the connections under the engine mounted circuit breaker. This feeds the helm instruments. Attached is a pic.

And so you you are not driving blind as to what is actually happening at the batteries consider the DVM install:

Installing Digital Volt Meters (DVM) on Your Boat

We’ve just added an assortment of DVM faceplates:

SMX Digital Voltage Monitor

[Nicholas]

I had a chance to take another look this weekend and the mixer on the starboard side is not as “flat” as it appears in the pictures I posted. I need to measure the actual slope to get the installation angle to see if it’s anywhere close to the 15 degree minimum but it’s certainly downhill, similar to the port side. I’ll take some measurements and post when I have some actual numbers, as well as pics once I can get a look inside the turbo outlet. Can I just disconnect the dry exhaust elbow in place and snap a picture of the turbo in place or will i need to disassemble it?

Meanwhile, I ran the boat for a couple of hours and while I still don’t have visibility into the fuel burn data, I’m posting a pic of my gauges at ~2200 RPM. In this boat that corresponds to about 24 kts, or maybe 25 kts if i add just a touch of tab.

I noticed that my stb voltage is low – only 12V at cruise and about 11 or even a little under 11 at idle. Engine cranks just fine, so I need to put a meter on the battery to make sure it’s not just a faulty gauge. Otherwise I’m guessing it’s a bad battery? Or should i suspect the alternator?

I think the other levels look normal. Can anyone tell me what the two pressure gauges are that are reading about 275-300 psi and whether those readings appear normal at cruise? I’m guessing maybe its coolant pressure? Fuel pressure? It is not shown in the 480CE manual, so I’m guessing it must have been some sort of add on.

[Tony Athens]

Cummins Exhaust Design thoughts

You might read the attached to get Cummins view on wet exhaust design.. Notice the terms “at least” and “Minimum” .. They are there for a reason..

Tony

[Nicholas]

Checking the propping is definitely a priority. I’m working on a solution right now to be able to view the engine data (existing displays are shot so all I have is the analog gauges to go off). Unfortunately though I paid thousands of dollars for an engine survey, the diesel surveyor did not save the file from the sea trial while he had his laptop hooked up, so I don’t even have those data. Very, very frustrated about that.

Aftercoolers will be serviced and checked this off season as well.

After taking and posting the photos, I went back and re-read the post on “exhaust system design” and looking at the photos had the exact same concern. When I was looking in person I don’t remember the mixer looking that “flat” but regardless it would make me feel a lot more comfortable if it had a better slope. The thought of the boat rocking in a beam sea definitely makes that setup look inadequate.

[Rob Schepis]

Tony Athens wrote:

… Your exhaust mixer, at least on the port engine, is very flat and does even come close to what Cummins requires as to a “down hill slope”.. Water getting back into the turbo?

To further this comment and concern —– that “flat run” is a side to side run… put this flybridge Bertram in a beam sea and whatever downward pitch is in that section of the exhaust is gone real quick..

[Author]

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