420 DA Thread

I've got my eye on a 2003 420DA that's about 3 hours away from me. It's on it's 3rd owner, and started out as a freshwater boat except for a couple of years in Florida. It has the Cummings 6CTA 8.3 engines (1100 hrs) and an Onan genset (1300 hrs). As a complete neophyte to diesels, are there any "tell-tale" signs I should look for on a first look-see visit. Naturally if the stars align correctly, a full engine survey would be a must. I have asked about things like if A/C units have been replaced, refrigerators replaced, and when (and who) has serviced the engines/genset? Any other things I need to put on my list of things to check? About the only things I've gotten from the broker is it had a bottom job done last year, and "it shows real well."
 
I've got my eye on a 2003 420DA that's about 3 hours away from me. It's on it's 3rd owner, and started out as a freshwater boat except for a couple of years in Florida. It has the Cummings 6CTA 8.3 engines (1100 hrs) and an Onan genset (1300 hrs). As a complete neophyte to diesels, are there any "tell-tale" signs I should look for on a first look-see visit. Naturally if the stars align correctly, a full engine survey would be a must. I have asked about things like if A/C units have been replaced, refrigerators replaced, and when (and who) has serviced the engines/genset? Any other things I need to put on my list of things to check? About the only things I've gotten from the broker is it had a bottom job done last year, and "it shows real well."
Seawater pumps if they are original.. they have the potential of losing seals and leaking oil... Replace with these https://www.sbmar.com/product/smx-1730-seawater-pump/
Heat exchanger and after cooler serviced recently

When I bought mine I had Cummins Do the engine survey... Do the oil samples thru them.... A lot of time the mechanic has a service history on the engines...

Good luck
 
What Blueone said. The raw water side is the achilles heel, so to speak of these engines. As long as proper maintenance is performed, no problem. BUT, you need proof of said work. When I bought my boat, as a condition of sale, we pulled both aftercoolers and heatexchangers. Glad I did as the Port aftercooler was fused. $3,400 in parts later! If you go this far, you may as well change the gear oil coolers too. When the aftercooler is off, they are right there.

If there are any signs of leakage around the raw water pumps, change them!

Be sure to check ALL of the floor hatches. Especially the small one in the aft cabin. Look for water! If the grey water sump is all scuzzed up, it will give you a general idea of how the boat was maintained, in my opinion. Not a deal killer, but it would indicate that you need to be more thorough.

Jaybeaux
 
As Blueone said above. The engines should have had 1,000Hr service done. Ask to see those receipts. If not done, plan to have it done. "The bottom was just done last year and it shows real well" is not enough information one way or another. Get your questions addressed as well as the maint records from the Broker.
 
On your first look at the engines you want to look for three things:

1) cleanliness - are there oil or coolant streaks running down sides of engine? If yes there is at a minimum a lack of attention to the engines, at works you have seal leaks or blowby.
2) rust/paint - is there a lot of rust, or conversely if there is no rust does it look like someone just spray bombed the engines to cover the rust
3) are the turbos a light tan color or dark brown - turbos generate a lot of heat, as a result they will often turn white paint to a nice light tan color - totally normal. If a turbo or even worse an aftercooler is dark tan or brown its a very good sign the engines were run hard for long periods of time.

all the other things mentioned before are important as well, but those are more questions for the owner and/or surveyor. The items above are easy to spot and will take 3-5 minutes per engine to get an overview.


Its been a while since I was on the market for my 42/44 but my memory says the hard top was an option on the 420 in 2003. IMHO, the hardtop is well worth the extra money to get it!
 
Here is an idea of the turbo color to look for... also cleanliness... and if you look really close.. Hug marks :)... you will love those engines

Engine Strbd.jpg
 
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I agree about cleanliness and receipts. To me those are the first things I'm using to decide if we're moving forward with any particular boat... a diligent previous owner ought to have an organized set of receipts for any and all services and parts. Annual/regular: oil changes, exterior and pencil zinc receipts, bottom paint, fuel filters, winterization products/services, serpentine belts, impellers etc. etc. If not just remember there will ALWAYS be another boat to consider.

I remember when I bought my boat about 6 years ago the previous owner had all of the above for me to see. Also, the boat and engine room were very clean. These made my decision to spend money on an engine and hull survey easy.
 
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I also have an 03 with the same power setup. Agree with the sentiments above. I'm still felling my way though - but so far I love the boat!
 
Cold beer is served once again..

The original inside fridge was not cooling so I had my guy come out and take a look. The fan and AC converter on the fridge were not working properly. We replaced both. He had an upgraded module that was the controller and AC converter combined for just another $100 more($350 total for the part). All in all three hours labor and parts, $750ish and we have cold beer once again. I attached a couple pics so you know what too look for if you are a DIY type. The pics are of the setup and then the replaced fan and controller. I didn't get a chance to snap pics of the new setup.

After hearing the story about the fragile cooling lines, I chickened out on DIY aspect.

From what I gathered these are dc fridges that have an AC converter.
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I'm kinda curious about people's thoughts on occasionally using barnacle buster through the raw water side of our engines??? Obviously not as a replacement for the recommended aftercooler and raw water tear down. Thoughts? Pros and cons??
 
So, this question came to mind as I was recently viewing Sea Flush you tube videos on engine winterization techniques. One of their videos was about use of Barnacle Buster with their Sea Flush product which I happen to own.
 
Was curious about this myself. Dockmate has a 400 DB with Cats and says he uses it every other year.
 
It wont hurt, but not sure it will help either unless when you open them up after 2 (or 3) years they have a lot of internal clogging.

The issue with these aftercoolers is less about the clogging and more about the interaction of the different metals, which is why tony calls for splitting them and lubricating the surfaces.
 
The PO apparently used Barnacle buster every season. I plan to take the aftercoolers off in a month or so and rod out the heat exchangers. The coolers haven't been off in 5 years so we shall see how well BB worked. I'll update the thread with my observations when complete. Personally i don't plan to use BB, but also don't think its bad for the engines if used as directed. Some people claim its bad for the gaskets, but who knows how much credence is in that. I would rather take it apart and clean it properly every other year and fresh water flush throughout the season.
 
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The PO apparently used Barnacle buster every season. I plan to take the aftercoolers off in a month or so and rod out the heat exchangers. The coolers haven't been off in 5 years so we shall see how well BB worked. I'll update the thread with my observations when complete. Personally i don't plan to use BB, but also don't think its bad for the engines if used as directed. Some people claim its bad for the gaskets, but who knows how much credence is in that. I would rather take it apart and clean it properly every other year and fresh water flush throughout the season.

Keep us posted when you complete!! Thanks
 
It wont hurt, but not sure it will help either unless when you open them up after 2 (or 3) years they have a lot of internal clogging.

The issue with these aftercoolers is less about the clogging and more about the interaction of the different metals, which is why tony calls for splitting them and lubricating the surfaces.
I guess my real question would be if it allows you to go longer on the heat ex changers? I understand having to remove the aftercoolers at the recommended intervals for servicing but does this also applies to the heat ex changers and oil coolers as well if you flush them annually?
 
I haven't touched the oil/gear coolers til this year. Cummins dealer said it was time to replace them. Simply based on years . engine have 1200 hrs . only saw a 5 degree temp drop... Also my engine impellers were 4 yrs old ... they came out pristine looking as did the previous set that again were 4 years old . Just my 2 cents.

Rob
 
I started investigating putting a dinghy on the swim platform. I don't have a hydraulic lift, so I am looking at a Hurley H30. I am starting to second guess the size of the dinghy. I want 10'-2" x 5'-8" but starting to think it might be too big or not look right.
Can any of you tell me what size you have and any pictures of the stern with the dingy on the davit would be appreciated.
 
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