moving up

[bnoft]

We've owned a 42' Grand Banks for the past 10 years and have listed her for sale. Our thought is to move up to a 53 Hatteras Classic; we like the aft deck better than the ED version. Looked at a couple that need serious work but been there done that; interested in a "cared for " boat. We have taken our grand children for 2-3 day cruises and hope to continue that, one reason for larger vessel. There are 3 or 4 53s in our yacht club so I have seen what a well maintained boat can look like. Our GB is powered by Cummins so the 8-71 DDs will be a learning experience.
Question for 53 owners, I understand that a 53 cruises comfortably at 12-15 kts and tops out at 19-21 kts. Running at WOT for any length of time is not good for any engine but how does a 53 with 8-71s like 15 kts? Is that within sustainable parameters? I assume fuel burn at that speed (about 17-1800 rpm?) will be more than what I'm accustomed to with a lighter boat.
Thanks, already learned a lot reading older posts, I have a long way to go.
Bill

[bobk]

A 48' Series I MY will also provide a very large aft deck and will run well as a trawler too. Pics in my profile if you are interested.

Bob

[MadHatter53]

Is your boat for sale Bobk ?

[bnoft]

Bob
The 48 is a great option, I especially like the steps from the aft deck to the flybridge. But I think the 48s are powered by 8-92s, which I understand can be more problematic than the 71 series. What are your engines?

[SEVEN]

I own and love our 53. Very spacious. Built like a tank.

[Boatsb]

Bob
The 48 is a great option, I especially like the steps from the aft deck to the flybridge. But I think the 48s are powered by 8-92s, which I understand can be more problematic than the 71 series. What are your engines?

I'd take. 92 series over a 71 any day. Not just because it's newer technology and larger displacement but usually not run hard in motoryacht.

Bobk puts a lot of time on his engines and maintains them well. I'd not pass over his boat as an option if it's offered for sale. He takes great care of it.

[Pascal]

12 to 15 kts in any boat that size range is just about the worst possible speed. Either you stick to 9kts and fail about 9gph or get fully in plane at 16/17 kts. At 12kts you ll burn over twice the fuel than you would at 9kts T

[bobk]

I'd take. 92 series over a 71 any day. Not just because it's newer technology and larger displacement but usually not run hard in motoryacht.

Bobk puts a lot of time on his engines and maintains them well. I'd not pass over his boat as an option if it's offered for sale. He takes great care of it.

Scott, my DD mechanic sure agrees with you on the 92s. He is certified on many brands and has rebuilt a lot of engines. Just a couple of weeks ago he offered that the 92 is also much easier to rebuild than a 71. I have motor yacht frinds with 671 TIBs who only get 1500 hours between rebuilds.

Bobk

[bobk]

Bob
The 48 is a great option, I especially like the steps from the aft deck to the flybridge. But I think the 48s are powered by 8-92s, which I understand can be more problematic than the 71 series. What are your engines?

My engines are 6V92 rated at 425 HP. These are well below the 1 HP per cubic inch measure and so would be considered to be low load engines. The bad reputation of the 92s comes from their use in sport fish where they are high HP and run on the stops. I'm not aware of an 8v92 in a 48MY. There were some 671 NAs but they are the rare boat.

The life of these engines has been discussed many times here. The best advice is to relate it to fuel burned assuming proper maintenance. Mine have been run at 1000 RPM, making 8.2 knots at 5.5 gph. Historically I average 1.3-1.4 smpg including the generator burn.

Bobk

[bobk]

Is your boat for sale Bobk ?

It is not listed, but I have been giving it serious consideration. We will not be cruising her north any more and so we are wondering if keeping a big boat makes sense. Bottom line is I'm on the fence and could be knocked off with a good offer. I'd be happy to discuss it with any one who is interested.

Bobk