420/44 DB Owners Club

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.
Thats all great news. Sounds like you found a good previous owner.
 
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?
Valve lash adjustment should be done around 600 hours. So if it hasn't been done, do it when you take ownership. Its not very expensive because the labor time is short. A few bolts are removed to take off the valve covers. Then about 30 seconds on each cylinder with a gap tool, then tighten valve covers back down. When I had it done the Cummins mechanic did not replace the valve cover gasket. I think my total cost for his time was in the $200 range. He also told me once you do the 600 hour lash adjustment, that it pretty much stays good from then on. Your mechanic may have a different opinion on that, so check that with them.

Cooling system cleaning is a time thing for me. I do it every 2 years regardless of hours. Actually I have found the more I use the boat, the less crud builds up in cooling tubes in the two years. On each engine you have a gear oil cooler, an after cooler, a fuel cooler, and a heat exchanger to check and clean each time, and an impeller to change. Its pretty easy to do yourself if you want to, just takes the mindset to go through it one step at a time.
 
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.

I'm hoping the boat to run closer to 2700 rpm due to only 25% of fuel and the boat would appear to be light. There will be 6 adults on board. I would prefer the boat to be 5% underpropped. Will advise after Wednesday.
 
Valve lash adjustment should be done around 600 hours. So if it hasn't been done, do it when you take ownership. Its not very expensive because the labor time is short. A few bolts are removed to take off the valve covers. Then about 30 seconds on each cylinder with a gap tool, then tighten valve covers back down. When I had it done the Cummins mechanic did not replace the valve cover gasket. I think my total cost for his time was in the $200 range. He also told me once you do the 600 hour lash adjustment, that it pretty much stays good from then on. Your mechanic may have a different opinion on that, so check that with them.

Cooling system cleaning is a time thing for me. I do it every 2 years regardless of hours. Actually I have found the more I use the boat, the less crud builds up in cooling tubes in the two years. On each engine you have a gear oil cooler, an after cooler, a fuel cooler, and a heat exchanger to check and clean each time, and an impeller to change. Its pretty easy to do yourself if you want to, just takes the mindset to go through it one step at a time.


If you were to hire this out, what would be the expected costs?
 
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?

Ok, now I see a problem: 50 hours per year is not enough time spent on your boat!

Re: valve adjustments/valve lash: Is that an 800 hour service or 1000 hour service?
 
If you were to hire this out, what would be the expected costs?
Some who hire it out have reported big labor dollars for this (well, big for me). Hopefully some of them will see this and post their experiences.
 
Ok, now I see a problem: 50 hours per year is not enough time spent on your boat!

Re: valve adjustments/valve lash: Is that an 800 hour service or 1000 hour service?
Valve lash adjustment is recommended every 500 hours by Cummins.
 
Rydlyme cleaning of raw water system was $115 parts, $400 labor in 2016.

Aftercooler work (after I back out the $3,400 for new AC) was approximately $1,200 in 2016.
 
Valve lash adjustment should be done around 600 hours. So if it hasn't been done, do it when you take ownership. Its not very expensive because the labor time is short. A few bolts are removed to take off the valve covers. Then about 30 seconds on each cylinder with a gap tool, then tighten valve covers back down. When I had it done the Cummins mechanic did not replace the valve cover gasket. I think my total cost for his time was in the $200 range. He also told me once you do the 600 hour lash adjustment, that it pretty much stays good from then on. Your mechanic may have a different opinion on that, so check that with them.

Cooling system cleaning is a time thing for me. I do it every 2 years regardless of hours. Actually I have found the more I use the boat, the less crud builds up in cooling tubes in the two years. On each engine you have a gear oil cooler, an after cooler, a fuel cooler, and a heat exchanger to check and clean each time, and an impeller to change. Its pretty easy to do yourself if you want to, just takes the mindset to go through it one step at a time.

Shouldn't the salt water pump and impeller be done too? Also, is the gear oil cooler the same thing as the transmission cooler?
 
Shouldn't the salt water pump and impeller be done too? Also, is the gear oil cooler the same thing as the transmission cooler?
Yes on the impeller. I modified my post to include that in the two year maintenance. The pump should last 10 years or so, especially if you get the SMX pump sbmar.com sells (that's what I replaced mine with). Yes, the gear oil cooler is the transmision oil cooler.
 
Yes on the impeller. I modified my post to include that in the two year maintenance. The pump should last 10 years or so, especially if you get the SMX pump sbmar.com sells (that's what I replaced mine with). Yes, the gear oil cooler is the transmision oil cooler.

Thanks, I'm noting everything you've suggested. What would be your maintenance schedule for the gen set? We have an Onan 9kw with 1400 hours.
 
Happy to see another 420/44 owner out west! Hope all goes well with your survey. It sounds like the PO took care of the boat and didn’t scripm on service and maintenance.
Keep us posted
Carpe Diem
 
Thanks, I'm noting everything you've suggested. What would be your maintenance schedule for the gen set? We have an Onan 9kw with 1400 hours.
I have a Westerbeake. I change the oil and filter once a year, change the impeller once a year, change the small inline fuel filter on the engine every 300 hours, and change the coolant every 500 hours. I also annually take the end caps off of the heat exchanger and inspect and clean the cooling tubes. I use my generator enough that I have yet to find anything in there to clean out.

You also have zincs on the engines and generator to keep track of. On the main engines there are three zincs. Two on the aftercooler and one on the heat exchanger. The heat exchanger and top aftercooler zincs will last quite a while (maybe a year). The zinc at the bottom of the aftercooler goes fast. Check it monthly.

I have a maintenance schedule I maintain for the Cummins 6CTA engines. If you'd like a copy just message me your email address.
 
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zz13, got your maintenance schedule - thank you very very much it's going to be really useful. Our sea trial went well today. Overall a properly maintained boat, according to the mech. surveyor and systems surveyor. Needs a few things but I"m sure we can work those out with the seller (nothing that'll kill the deal) although we are still waiting for the oil samples).

In the meantime, I'd like to ask if there's a way to order the galley sink cover that'll match the countertop. Does Sea Ray sell them based on hull id numbers so they'll match? Also would like to find the ottomans that tuck under the salon table (hopefully I can find those to match the settee leather fabric). Lastly, the flybridge filler cushion is missing so I need to find one of those too. If anyone knows who at Sea Ray I can contact on ordering these items or better yet if someone isn't using theirs I can buy theirs. Let me know !
 
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Ok, I have read though this thread completely, I think, and also the QSC-500 thread, looking for information about changing the fuel filters/separators, but I don't have solid understanding on one part.

My understanding is the primary Racor's need to be topped-up with diesel, and I am clear on how to do this. I am not clear about the secondary, engine-mounted spin-ons. Some instructions are to fill them up, others are to install and prime by cycling the ignition on and off to make sure contaminated fuel doesn't get by the filtration.

After buying this boat last fall, I had the marina in Plymouth, MA do quite a bit of preventative maintenance, including all new filters, but I am still new to diesels, and this boat in general. I have read all the documentation I can find, but I haven't found clear direction on this.

Can anyone help?

Thank you!
 
Although I have a 44DA I do have the same engines you have.

The primary Racors get topped up with fuel.

The on engine secondary filter should go in dry (but you should lube the gasket with a bit of clean fuel for a better seal). Once that is on you cycle the start switch on (but don't crank) for 20-30 seconds (you can hear the pump run during this time then shut off), then shut off for 5-10 seconds and repeat 10-15 times. If you change both filters at the same time, you probably need to cycle more like 15-20 times.

The reason it goes in dry is because you don't want to risk getting dirty fuel in the fuel rails. By priming this way you filter every bit of fuel.
 
Hey all,

Some say that the two happiest days of a boat owner are the day they buy their boat and the day they sell it. I can confirm the first, but not necessarily the second. After over 30 years of boating, we have decided to sell our 2005 Sea Ray 420 Sedan Bridge. We closed on the transaction on Friday.

I became a member of this site and this thread last year, and found it to be extremely helpful. I am not very mechanically inclined, but tried to help others as best as I could. But despite my best efforts, it seems I always got more and better advice from all of you than I was ever able to provide to all of you.

So, I just wanted to leave active participation by taking a moment to thank all of you for being so engaged and helpful. I especially would like to thank Alex and Carpediem for specific counsel they provided me.

We are a little melancholy but with nine grandchildren to spoil, we have just run out of time. Mary and I wish you all great weather, great water, and great relaxation and much enjoyment in all your future travels.
 
Our Cummins 6cta 450 diamond engine has a max rpm 2600. There should be a formula that suggests max rpm for cruising. it's been suggested to me that I should just subtract 10% from max rpm of 2600 for a max cruise of 2340??
 
Hey all,

Some say that the two happiest days of a boat owner are the day they buy their boat and the day they sell it. I can confirm the first, but not necessarily the second. After over 30 years of boating, we have decided to sell our 2005 Sea Ray 420 Sedan Bridge. We closed on the transaction on Friday.

I became a member of this site and this thread last year, and found it to be extremely helpful. I am not very mechanically inclined, but tried to help others as best as I could. But despite my best efforts, it seems I always got more and better advice from all of you than I was ever able to provide to all of you.

So, I just wanted to leave active participation by taking a moment to thank all of you for being so engaged and helpful. I especially would like to thank Alex and Carpediem for specific counsel they provided me.

We are a little melancholy but with nine grandchildren to spoil, we have just run out of time. Mary and I wish you all great weather, great water, and great relaxation and much enjoyment in all your future travels.
Johnny, hate to see you go! I totally appreciate the concept of knowing when to get out, these yachts are just too complex and expensive to sit and be seldom used. I wish you and your wife years of happiness spoiling the grand kids, you only have so long to do that, you can always get back into a boat.
Cheers
Carpe diem
 

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