420/44 DB Owners Club

Bit of a long post here, lots of new things to understand!

So we finally got our new purchase up to the chilly water up North. Fairly uneventful trip, other than a partially submerged tug boat in the one of the Erie Canal locks.

Boat ran well, with only one real issue, and a couple of observations. I am hoping to get some opinions and advice on them.

We left Plymouth, MA and the boat ran well with no unusual readings the first day. The second day as we were getting close to NYC, I noticed a differential in the boost pressures. On the sea trial, both engines were showing around 60 psi +/- 1 psi at 2400rpm. This was also what we saw on day 1. On day 2, the port boost dropped to around 28-30 psi. Engine performed identically, no smoke, etc. Tried WOT, right on at 2680 RPM. Everything stayed the same until day 4 when the starboard boost also dropped to 28-30 psi. No change in performance.

20 hours of motoring later and they are still both within 1 psi of each other, around 28-29 psi at 2300-2400 RPM. I spoke to the gentleman who did the engine inspection (Doug Gorham at Gorham's Diesel...great guy, BTW), and he doesn't think it is anything to be concerned about. Any opinions? Reading other posts, it seems around 30 psi is typical. I am curious what others see, and what may explain the 60 psi readings we initially saw.

Another observation is that at around 800-1000 RPM, there is a small shake or shudder...I would describe it almost as a wobble. It is not present at idle speeds nor once up on plane. I was able to isolate it to the starboard engine. The marine surveyor showed me some play in the starboard cutlass bearing, and stated in his report "The starboard propeller shaft strut cutlass bearing found to have some minor play when checked. It is suggested cutlass bearing be renewed winter layup 2018-19".

I am new to straight shafts and cutlass bearings. Would it make sense that what I am experiencing is due to the cutlass bearing? The boat didn't get much use the last couple of seasons...it is possible the bearing deteriorated quickly with the fairly rigorous use of quickly getting north.

Last one, and this was the most significant, although there was an easy work-around. About halfway through the trip it was noticed the engine alternators were not putting out any volts. It seemed surprizing to me that both would fail. They were confirmed operational during the survey / inspection. It was masked somewhat as we were running pretty much all the time with the generator running, and the battery charger on.

A few points and questions about this:
- We did have the house battery charger on when underway. Unnecessary, I know, but being new to the boat and not confident about what batteries were charged by what (e.g. is the generator battery only charged when the charger is on, or does the generator itself charge it, etc.), we left it on under the presumption it would not harm anything. Bad presumption?
- At no time were the battery solenoids turned off.
- The belts were replaced by the marina before we left (based on advice from this and the QSC-500 thread!), and confirmed installed correctly.
- The problem was highlighted when the generator was not run one day, and the batteries ran down after about 10 hours...kind of quickly, I thought.
- Only getting about 12.4V (then slowly dropping) on both engines when underway (and no charger on), and there is no SmartCraft fault, which is strange.
- Could a faulty battery, isolator, or solenoid be the culprit?
- I will measure voltage directly at the alternators this weekend, but I assume the reading will be the same as what is reported by SmartCraft. Is this logical?
- Am I missing something obvious here?

As always, this forum is an incredible resource and wealth of information!

Brian

As for the boost pressure, I would make sure the air cleaners are very clean and oiled properly. Diesels need clean air. Had a friend of mine with a 48DA with the air cleaner partially sucked into the turbo because the air cleaner was so dirty. Just a thought.
 
New Guy to the club,
New to the forum and new 420 Sedan bridge owner.
Purchased a 2005 420 Sedan Bridge "Pura Vida dos" In July! Love it!
Blue Hull, Cummins 480ce's w/200 hours. Mods / upgrades since purchase, Garmin 7612 chartplotter, Simrad vhs w/AIS Rocna 55lb anchor,led bulbs & lights throughout, Custom bamboo flooring in salon, galley & dinette. Also Freedom Lift tender lift to carry Highfield CL340 with euro console & 25hp Suzuki.

View attachment 51524


Previous boat "Pura Vida" a 1987 410 Aft cabin wCrusader 454's. She served us well for great Michigan summers & a full year on the great loop!

Now headed south with the new boat, Northern summers are so short.
In the words of Jimmy Buffett
"I Gotta go where it's warm!"

Thanks for all the great info on the forum, Happy boating!
Great boat! We love ours. Have you learned of and looked into the potential valve seat problems on the 480CEs? Be mindful of your power settings and loads that you cruise with if the heads have not been changed. Read up on the issue on SB Marine’s site.
Enjoy your journey south.
 
New Guy to the club,
New to the forum and new 420 Sedan bridge owner.
Purchased a 2005 420 Sedan Bridge "Pura Vida dos" In July! Love it!
Blue Hull, Cummins 480ce's w/200 hours. Mods / upgrades since purchase, Garmin 7612 chartplotter, Simrad vhs w/AIS Rocna 55lb anchor,led bulbs & lights throughout, Custom bamboo flooring in salon, galley & dinette. Also Freedom Lift tender lift to carry Highfield CL340 with euro console & 25hp Suzuki.

View attachment 51524


Previous boat "Pura Vida" a 1987 410 Aft cabin wCrusader 454's. She served us well for great Michigan summers & a full year on the great loop!

Now headed south with the new boat, Northern summers are so short.
In the words of Jimmy Buffett
"I Gotta go where it's warm!"

Thanks for all the great info on the forum, Happy boating!


Steve and Shelly, Welcome and wow small world and Nice Boat!
It was a pleasure to have met up with you guys while looping up in Canada back in '15. We went gold in August. It sounds like maybe we are thinking a lot along the lines that you guys are, finish the loop and take a year off to position ourselves to do more traveling by boat. Hopefully we will see you next year along the way.
This is a great place to Hang out and learn a lot about your new boat, there is a lot of good info in this thread and a lot of experience in the other 420/44 owners.
Have fun and safe travels.

P.S. Here's another one for that loop photo album :)
peterborough Lift Lock.JPG
 
New to Club, but long time SR Owner, so please excuse any "Forum" faux pas'.
5 years ago I bought a 2004 420DB with 480CE's. Love the boat and do most if not all the maintenance myself (with the exceptions of outboard impellers, if you get the drift).
Anyway, I think I need to replace my salon A/C and trying to figure out how to access it. Does any of the A/V panels come apart or ???

Any help would be appreciated...thanks
 
New to Club, but long time SR Owner, so please excuse any "Forum" faux pas'.
5 years ago I bought a 2004 420DB with 480CE's. Love the boat and do most if not all the maintenance myself (with the exceptions of outboard impellers, if you get the drift).
Anyway, I think I need to replace my salon A/C and trying to figure out how to access it. Does any of the A/V panels come apart or ???

Any help would be appreciated...thanks

Welcome aboard.

Outboard impeller is not as hard as you think. Do a "training run" with the STBD side and then do the port. It all depends on the method/tools you use. On the PORT side you'll be doing mostly everything with your left hand. The easiest I found is laying on a blanket over the engine. All in all it takes me extra 15 min for the outboard side. I religiously change mine every year.

To access salon A/C, under the entertainment center, open the cabinet and you'll see the back panel with small (~1 1/2") round hole in mid top section. The panel is held by small velcro strips on each corner. So, the hole is made to make it easier to pull the panel off.

Another tip:
The A/C swap should not be difficult, but if you have never done it, take a good look on how everything is setup on the one in the master state room. The access there doesn't get much easier, just lift the front side of the bed and then the access panel. By analyzing how everything is mounted and hooked up, you can have a good game plan for the salon unit.

Good luck.
 
Thanks for the reply and appreciate the help, but I know how to change the impellers, it's just my girth prevents accessing the outboard pump. Also, I know about the Velcroed panel as I've changed A/C high pressure switch and cleaned the filter annually. But there is no way that a/c will fit through that hole, much less me getting good enough access to the bolts, etc. The whole thing must come off somehow.
 
.... Also, I know about the Velcroed panel as I've changed A/C high pressure switch and cleaned the filter annually. But there is no way that a/c will fit through that hole, much less me getting good enough access to the bolts, etc. The whole thing must come off somehow.

I could be wrong, but based on my observation that opening under the entertainment center is the largest one I could think of and that's how I would try pulling the A/C out. If you lay the unit on a side, it should fit through there.

The only way I can think of getting to the unit from the top, is to take the face panel where the A/V head unit with CD changer is mounted. The only other area that might get you closer to the forward side of the A/C unit (at least to loosen mounting screws) is crawling behind the STBD sofa seat.

If you find a better way, let us know.
 
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I replaced mine on my 44 DB. The whole unit comes out through the opening in the lower cabinet. As I recall I removed the doors for maximum access. I installed a new stainless steel unit that I bought from Mike Potter at Noah’s Ark Marine. It’s a pretty straight forward project. Unit is totally self contained and came fully charged with coolant.
Cheers
 
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Well, thought I'd wake up this thread and ask a question: We have our survey, sea trial & haul out this Wednesday. Anything special I need to look out for?
 
What motors does it have? Assuming 480CE. Take the engine serial numbers and call Cummins and try to get the records. In my experience, some Cummins dealer’s systems don’t integrate to corporate so you should call all nearby Cummins service centers too.

This boat with the 480CE was allegedly over propped which led to valves dropping into engine if run hard. I’m no expert, but you can find experts at boatdiesel.com (2nd best boat web page IMHO, and worth subscription).

Good luck!
 
What motors does it have? Assuming 480CE. Take the engine serial numbers and call Cummins and try to get the records. In my experience, some Cummins dealer’s systems don’t integrate to corporate so you should call all nearby Cummins service centers too.

This boat with the 480CE was allegedly over propped which led to valves dropping into engine if run hard. I’m no expert, but you can find experts at boatdiesel.com (2nd best boat web page IMHO, and worth subscription).

Good luck!
I may have misunderstood. Are you buying a 2005 420DB? Just noticed you had several other posts.
 
yes 2005 420 Sedan Bridge but the engines are stated as Cummins 6cta 8.3 430 hp.

Ok, I think you should be good then. Here is some info from boatdiesel.com on your engines: https://www.sbmar.com/engine-info/cummins-6cta-specifications/

I'd make sure the PO has kept good records, and verify that everything is on schedule with the diesels. Some of the scheduled maintenance is pretty expensive (i.e. valve adjustments), and you don't want to skip maintenance with a diesel.

If the boat came from a salt water environment then you're going to need to make sure the aftercoolers have been serviced on a continuous basis (Tony Athens has some great write-ups on this at boatdiesel.com).

My opinion is that you need to have two distinct surveys done: one for hull and other systems, and one for the motors. You want a qualified diesel guy to do the motors. Diesels are great but they are very expensive to replace, so you want to have your eyes wide open when you're ready to commit.
 
JoAna, you MUST verify the condition of the raw water cooling train. Primarily, the after-coolers. The after-coolers (AC) cool the air from the discharge side of the turbo-charger before sending it to the engine. Depending upon where the boat has been used (saltwater or freshwater) will depend on the frequency of service. Sometimes, these are neglected, and the element becomes fused to the housing. The new parts from Cummins are around $3,400. These should be removed, inspected, cleaned, re-greased and replace O-rings.

The next piece of the raw water train to look at is the Raw Water pumps themselves. If these are original to the boat, check for signs of seals leaking water. The original design had a flaw of sorts so that when the seals leaked, they corroded the shaft. If the shaft fails at speed, you cannot shut your engine down fast enough before it overheats. Sherwood has a new replacement pump as does Seaboard Marine. If they've never been changed, change them.

The heat exchanger should be inspected for cleanliness and most importantly pieces of chewed up impeller vanes that have made it through the aftercoolers. A clean raw water system should maintain your engine at 160-165 degrees F.

Historical oil analyses will go far in telling you how the previous owner(s) have maintained the engines.

Removing the Walker Air/water separators will give you a peak at the Turbo Inlet. There shouldn't be any play in the rotor.

Inspect the idler pulley on the serpentine belt for excessive wear or the presence of "red dust". While there, check out the belt itself.

If your engines are equipped with grid heaters and they are functioning, it is a good practice to allow them to cycle once or twice prior to firing the engines. You can determine this by watching the voltage meter at the helm. When the grid heaters cycle, they pull quite a few amps and thus drop the voltage down to the 10 or so volt range. When they cut off, the voltage returns to the 12-13 volt range (analog gauges are hard to read any closer than that). By doing this, you will be throwing the proper voltage to your starter without any other/additional temporary demands on the batteries. As a side note to starting the engines: some owners will replace original batteries (Group 31) with smaller ones (i.e Group 27) do to availability, price or the simple fact that smaller batteries are lighter and easier to handle. If one side or both sides of your starting batteries only supply, say, 525 MCAs, then you can boost your starting punch by tying the port and starboard banks together electrically by holding down the emergency start switch on the helm.

I've been told by others that the 6CTA-8.3s are essentially bullet proof. Like many things, they need to taken care of. Another good habit is to use lubricity additives in your fuel. EPA regulations concerning the amount of sulfur in diesel fuel has had the negative effects, especially on "older" engines. Removing sulfur makes the fuel less slippery so to speak. You can combat this with additives.

Sorry for the long post. This is all based upon my own experience(s) and things that I have learned from others who are much more experienced than me. Good luck.

Jaybeaux
 
Jaybeaux hit all the important stuff. I have the same engines. The aftercoolers are a wild card. If the current owner doesn't produce good service records you have no idea what their condition is. Actually, I believe if there are no records that the internal condition is most likely poor. I have seen that time and time again on resale of these engines. And you can't pull them off and apart and look at them during a survey. The price of those things doubled a few years ago when Cummins switched manufacturers. At $3400 a pop, if there are no records I'd try to negotiate at least a 50-50 share of the cost of two new ones.

Also, those engines should turn at least 2600rpm at wide open throttle (WOT) when under a full load. See if somehow you can have the sea trial done with both tanks full of fuel and lots of water in the water tank. 2600 minimum under those conditions. 2650rpm would be even better. 2650 would give you some margin to add more weight to the boat. If you can't load up the boat for the sea trial take good record of what the load is (amount of fuel, water, number of people on board) and what the resulting WOT rpm is on each engine.
 
Ok, I think you should be good then. Here is some info from boatdiesel.com on your engines: https://www.sbmar.com/engine-info/cummins-6cta-specifications/

I'd make sure the PO has kept good records, and verify that everything is on schedule with the diesels. Some of the scheduled maintenance is pretty expensive (i.e. valve adjustments), and you don't want to skip maintenance with a diesel.

If the boat came from a salt water environment then you're going to need to make sure the aftercoolers have been serviced on a continuous basis (Tony Athens has some great write-ups on this at boatdiesel.com).

My opinion is that you need to have two distinct surveys done: one for hull and other systems, and one for the motors. You want a qualified diesel guy to do the motors. Diesels are great but they are very expensive to replace, so you want to have your eyes wide open when you're ready to commit.

PO claims port side raw water pumps, aftercoolers, impellers and turbo rebuild were done within the last 2 years and has already provided receipts. PO states that Stbd. side was also done and WILL provide receipts at time of survey. We are also having oil samples done for the mechanical survey with an extended sea trial to maximize the RPM, prop load and cylinder temps. By the way, the boat is located in Southern California coastal ocean.
 
Another question. Since the boat only has 700 hours on it and we expect to log about 50 per year, how often should I go through the cooling systems? We don't have to deal with the hours of the boat but more like the time in salt water. Should I be concerned with hours on the motors or time when taking valve adjustments into consideration?
 

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