Repower project

[Bradenvlp]

Hi All - A little background to set up my question. After a significant time looking for a boat in this category, my broker found an Offshore 55 before it came on the market. Remarkably clean boat and semi-recently rebuilt engines so we agreed to a reflective price. Hull survey went very well. Mechanical not so well.

Her 8V92's have about 400 hours on a rebuild completed by the owner before the seller - what I would guess was a bit of a "rattle can" job to get the boat ready to sell. The STBD engine has high levels of sodium, potassium, Iron.... All bad stuff. Both engines have manifold leaks that are expensive to fix. So I negotiated a new price with the seller that will cover approx. 60-70% of the cost of a repower and wired the $ yesterday. I am not interested in rebuilding the Detroit's. I know there are Detroit supporters in the forum and I have also had very good experience. But I'm not going to invest $ or time on these motors.

So those are my very bad financial decisions. But I'm going to end up with a boat I love with brand new engines of my choice at a price I can afford. And thus I need some help with the engine engine decision.

Does anyone have any direct opinion, innuendo, rumor, dock talk on my two finalists? Id love to hear. Boat will live in the PNW for service consideration.

1. Cummins QSC 8.3 at 550 or 600 HP. This was/is my first instinct and what all of the Cummins dealers have recommended (Seaboard, etc). Recons are an option if I am ok waiting which i am probably not.

2. JD 13L 6135SFM85, M3 or M4 550-625HP. This is an interesting engine a little off my radar. Bigger displacement (although I'm told that is not the way to think about modern engines) and similar RPM turn as the DD might mean less prop work etc.

Cat's have an availability issue so I think I'm down to these. Look forward to any thoughts!

 

[Ken E.]

Hi All - A little background to set up my question. After a significant time looking for a boat in this category, my broker found an Offshore 55 before it came on the market. Remarkably clean boat and semi-recently rebuilt engines so we agreed to a reflective price. Hull survey went very well. Mechanical not so well.

Her 8V92's have about 400 hours on a rebuild completed by the owner before the seller - what I would guess was a bit of a "rattle can" job to get the boat ready to sell. The STBD engine has high levels of sodium, potassium, Iron.... All bad stuff. Both engines have manifold leaks that are expensive to fix. So I negotiated a new price with the seller that will cover approx. 60-70% of the cost of a repower and wired the $ yesterday. I am not interested in rebuilding the Detroit's. I know there are Detroit supporters in the forum and I have also had very good experience. But I'm not going to invest $ or time on these motors.

So those are my very bad financial decisions. But I'm going to end up with a boat I love with brand new engines of my choice at a price I can afford. And thus I need some help with the engine engine decision.

Does anyone have any direct opinion, innuendo, rumor, dock talk on my two finalists? Id love to hear. Boat will live in the PNW for service consideration.

1. Cummins QSC 8.3 at 550 or 600 HP. This was/is my first instinct and what all of the Cummins dealers have recommended (Seaboard, etc). Recons are an option if I am ok waiting which i am probably not.

2. JD 13L 6135SFM85, M3 or M4 550-625HP. This is an interesting engine a little off my radar. Bigger displacement (although I'm told that is not the way to think about modern engines) and similar RPM turn as the DD might mean less prop work etc.

Cat's have an availability issue so I think I'm down to these. Look forward to any thoughts!

I have been down this road with you, removing Detroit 871n's, replacing them with Cummins 210 6bt's remans. I did this about 6 years ago on my present Hatteras.

You're right, you will attract comments saying that you should keep the 892's....easy to do an in-frame overhaul, Detroits are great, have some nostalgia, would you! Yada yada. I like 2-cycle Detroits, if someone else owns them, lives with the engine noise and oil leaks. The 1930's design is classic and the exhaust sound is great. But I don't want them. For me, give me a Cummins. I can't speak to Deere or Cat.

You will remove about 100 lbs of red 12 guage wire in the DD harnesses. You will remove about the same amount of congealed sludge and grease in the bilge with the engines out. Be sure to take the time to do a good cleaning and paint the ER with a good, hard paint.

On my repower, I intentionally powered down to displacement-speed power, the reason being that I like to go slow between here and Alaska. Beyond the fuel saved, there's lots of debris in the water that's easier to avoid at 8 kts rather than faster. The comment will be made that I won't get as much for this boat when I sell it because of these engines, compared to ones that would plane it. But I couldn't care less about that and the boat's resale will be greatly diminished from its age anyway. The value is in my use of the boat and its suitability to task, which is very good as the boat is now.

See if you can use your existing shafts and props, which will save you some money. I doubt that the gears can be used....in my case, the Allison gears that I had couldn't be used, and I needed a different reduction anyway.

Since you're in Seattle, I'd recommend that you talk to Tri County Diesel in Bellingham about doing your repower...they are factory authorized for Cummins, John Deere and Cat. Ask for Mike Rusk, the owner. They let me work along side of them as the project progressed....I got to do the scut-work but it saved a lot of billable hours on their ticket. They are honest and did a fine job for me.

PM me if I can help you with details.

 

[Lepke]

I love Detroits, but 92s I avoid. I think they pushed the design too far.

 

[IRENE]

My thoughts are with Ken on Tri County Diesel. Absolute integrity. Pleasant and generous owner, great tech named Travis, great parts department.

Good luck on the project, will be monitoring...

 

[Bill V]

My thoughts are with Ken on Tri County Diesel. Absolute integrity. Pleasant and generous owner, great tech named Travis, great parts department.

Good luck on the project, will be monitoring...

Another vote for Tri County Diesel, I can attest to their work rebuilding my transmissions 10 years ago, great work and service.

Go Cummins, would be my choice given the history of Cummins engines.

 

[twistedtree]

That's an interesting choice. I would have expected a Cummins QSM11, not the QSC 8.3. Given your choice, I would probably go with the Deere and the higher displacement. If it were a QSM11, I'd take the Cummins.

 

[Bradenvlp]

Thanks everyone for the referral. Great idea to connect with Tri County.

Ken, you are correct I will need new gear, hydraulics etc. However, good news is there isn't a speck of sludge. Engine room looks like a 2 year old boat.

Twisted - I hear you. I assumed QSM 11. I have talked to 3 big Cummins shops (2 in LA, 1 in Seattle) and they all recommend the QSC for this boat. I think if it was a big sporty I wanted to run 20 + kts it may be different. I did note that Fleming delivers their 55, at a very similar displacement, standard with QSC also. Ill keep asking.

 

[twistedtree]

I had QSC 8.3s on a 47 grand banks a number of years ago. It was a 20+ kt planing hull (one of the newer hull designs). They were excellent engines, but mine were rated at 500 hp. So you really have two good choices. I just lean towards a bit more displacement as opposed to pushing so much power out of a smaller engine.

 

[Rescator]

Hello
3 years ago we decided to re power our Grand banks 52 model 1998.
We removed our olds Cat 3208 (435HP heavy duty) and we put new Cummins QSL9 (405HP medium duty) we changed also Gearbox and Hydraulic pumps. We did all the work by ourself. (When I order the news engines asked Cummins to get them customised, plug and play) Ready to fix to avoid modifications in the engine room (Isolators, filters and exhaust)
I Paid in 2017 The 2 engines, gearbox and Hydraulic Pumps about 105.000$
On request I can send you a complete pictures file of the re-powering
PS : We did the work in France.

 

[Bradenvlp]

Thanks Rescator. I’m still punching a clock so this will be a professionally installed project for me. Note on first post typo - I’m removing 6v92 not 8v92.

 

[Ken E.]

Note to TT....Tri County Diesel is also a Scania dealer, if you're passing through these parts with your new boat and need some help.

 

[Nomad Willy]

The nicest thing about a repower is that you get to decide everything.

The most influential element of the equation is .. how much power.
Almost all trawlers are with SD hullform and can have a wide range of good power options .. unlike a FD that has basically only one choice.

One needs to determine what end of the SD range their boat is. Including displacement, Prismatic coefficient, beam/length ratio and others.
Most boats are overpowered and here is the only chance (most likely) that you’ll have to get it right. I’m not say’in boat builders and NA’s don’t know what they’re doing but they all need to address sales and the bottom line.
You can re-power to make your boat boat best for the market (as the builder did) or you can make small or large changes to better suit the hull or your intentions and circumstances.
When your boat was built most people thought “you can never have too much power”. So also due to the abundance of fuel and low prices most all SD trawlers were overpowered.

 

[ranger58sb]

Does anyone have any direct opinion, innuendo, rumor, dock talk on my two finalists? Id love to hear. Boat will live in the PNW for service consideration.

1. Cummins QSC 8.3 at 550 or 600 HP. This was/is my first instinct and what all of the Cummins dealers have recommended (Seaboard, etc). Recons are an option if I am ok waiting which i am probably not.

You might search for/review repower threads by a Captain named Pascal on either yachtforums or boatered... or maybe even both. He repowered his Hatt with re-man Cummins 8.3s (but not the more recent QSC version) and seems to be happy with that. I'd imagine QSCs could be even better, but dunno if there might be re-mans available...

-Chris

 

[Blissboat]

Following with interest, because I have passed on a few boats that were right in every way except for the engine(s). Others on the Forum advise convincingly against buying anything that needs a re-power, but there have been one or two cases where it was sorely tempting.

 

[Jon H]

We have 9,000+ hours on a pair of QSL 9's (2,100 RPM rating)
on a 40' pilot boat.

Overall they have been good engines, only one injector has been
replaced, all the rest are original.

 

[Rescator]

Nice to read.

 

[Sailor of Fortune]

The QSMs have had issues with cooling system. They have a less than Steller reputation at the higher end Your 8.3 CTA is a great choice, those are bullet proof. QSL has good reputation also.

 

[sunchaser]

The two Cummins go to sites for details are boatdiesel.com and sbar marine. Tony Athens at sbar will steer you right plus they do many Cummins installs.

Tony Fleming replaced the Cummins in his F65 with MANS and as of two years ago seemed quite pleased when we saw the install and talked with him. If I'm not mistaken, Delta in Sidney BC did the switchout, about as nice a exchange job as I've seen. Steve D'Antonio would have lots of details on this swap out.

Many Offshores in your size range had Cat 3196s. I'm not recommending that long discontinued engine but the vessel seemed to run well with that 12 liter displacement and may be your target CID range. TT suggested a JD in that size, a good choice too.

As Diver Dave suggested, carefully evaluate some Cummins engine models, especially those with dry exhaust manifolds that are soot producers in their higher HP configurations.

 

[FF]

One way to decide which engine to choose might be to price repair parts and shipping times.

How much is a new cylinder head , or set of pistons or even just a head gasket and set of rings.?

Sure these are seldom needed , but overheats and exhaust problems do happen .

If the old transmissions and props and shafting could be kept in place a large saving in time , effort and currency might result.

 

[Mako]

Braden, a couple of thoughts: First is to reread posts 2 and 12 and honestly decide how much power you need. If you spend significant time at 8knots then you’ll be running at about 10% load with 1100+ hp installed. Idle speed for weeks on end while cruising the Inside Passage.

Second, you could have delivered a couple of engines/gears from DCEC or CCEC Cummins in China, to Canada. Have them sent as export items and have a yard in Vancouver implement the work. Might be worth looking into.

 

[Rescator]

If you are able to found the cheap way to bring them in US, you can found in France some engines Detroit 6V92 marine with few hours at very very low price. (even some news or rebuilt never used)
These engines are rated 51 Horse (fiscal rating) for the annual tax . And if you have more than 100 (fiscal horse) power in your boat, the tax become very heavy . For a 25 years old boat with 2 engines 6V92 that's mind 102 hp fiscal tax is about 12000$/year. That's why these engines are now impossible to sell. (for information with 2 cat 3208 2x48=96 fiscal HP the annual tax become 1000$. The Fiscal HP is not calculate regarding the true power but only regarding the cubic capacity with a penalty of 30% for the 2 stroke.

 

[Bradenvlp]

Thanks everyone for your thoughtful replies. On a few questions -

-I would definitely have considered Canada (Vancouver or Sydney) for the project but there are some other cosmetic things I'll have done while in the yard and I don't want to do that via zoom call.

-I talked to Tony at Seaboard for quite awhile and he's familiar with the boat (the boat is in SoCal and I originally considered doing the project down there). Assuming I didn't want to drop way down in power, he was the first to fully recommend the QSC as the best Cummins solution.

As to the question several of you have asked on how much power I need (want) - that is a tough one. I run 8.5 kts. currently and am generally happy. But there are times when 12 or 14 sure seems like it would be nice to pace the following sea, get across the straight, get through some slop...

So fuel costs be dammed, I'd like to run hull speed (9.5 +/- kts) 90% and on step 10%. Is that worth the investment? Good question.

I will discuss with the shops but would be interested to know how the use case above would influence the engine choices I provided (other than entering into the lower end of the HP range in those models)? Cummins = smaller displacement, higher RPM & JD = larger displacement slower turning. You can let me know if this is a stupid question.

 

[ranger58sb]

As to the question several of you have asked on how much power I need (want) - that is a tough one. I run 8.5 kts. currently and am generally happy. But there are times when 12 or 14 sure seems like it would be nice to pace the following sea, get across the straight, get through some slop...

So fuel costs be dammed, I'd like to run hull speed (9.5 +/- kts) 90% and on step 10%. Is that worth the investment? Good question.

Devil's advocate... since you only focused on two engine options.

My guess is that the QSC 600s are a tad small -- HP vs. displacement -- for doing very much of your 10% on plane.

If QSMs aren't a viable option, or maybe QSLs if they still make those... I think I'd try casting a wider net to see what other engine options might be viable.

You mentioned Cat and availability problems... but did you mean engine availability? Or parts and service afterwards? And there are other makers; MAN probably has something in the right range...

If you extend your analysis first, and still don't come up with better alternatives on paper... at least you'll know.

-Chris

 

[Rescator]

For your informations.
On my GB 52 at Max weight (33 tons)
with my 2 QSL9 405 HP
At 1100 RPM 8,2 knots 7,8 liter/hour/engine
At 1200 RPM 9 knots 8,8 liter/hour/engine
At 1400 RPM 10 knots 18 liter/hour/engine
At 2150 RPM 17 knots 96 liter/hour/engine
At medium load (with only 2000 liter fuel, 500 liter water, black water tanks empty)
Weight 30 tons at same rpm/same fuel flow, speed increase 10%
Have nice trips

 

[ranger58sb]

My guess is that the QSC 600s are a tad small -- HP vs. displacement -- for doing very much of your 10% on plane.

Hmmm... I just reviewed a couple of Offshore listings on YW, one a 55' with 550-hp DD 6V92s... and the other a 54' with 660-hp Cat 3196s.

So maybe the QSCs are closer to the right ballpark than I first thought.

That said, I still think a more comprehensive engine review might help... if you haven't done that already.

-Chris

 

[twistedtree]

A Scania DI-13 would serve nicely as an alternative. 13 liter, and power ratings from 400 to around 700 HP. So far I'm real happy with mine.

 

[Bradenvlp]

Thanks, I was less familiar with Scania supply chain in the US but it looks like a great platform. I’ll discuss with the dealer. This 55 which has been part of my inspiration in making this stupid decision was redone with Scanias in Australia.

Cat has a long delivery time right now. I wasn’t feeling so compelled by Cat to add several months to a project. Maybe that is short sighted. MAN, I believe, starts their line at 730HP which is bigger than I am considering. That’s how I have boiled don’t to these two (possible adding Scania) after talking with several dealers. I haven’t considered / discussed Volvo with anyone I guess.

 

[RonR]

KTA19's?
19L 600hp almost matches your DD RPM range.

Im just shooting from the hip and have no real idea, but following this topic as one day I plan on doing the same thing.

 

[Bertram Guy]

I have a 2000 Offshore 62 Pilothouse with 3196 Cats 680hp. Previous boat was a Bertram 54 with 1292 Detroit's. The last time the Offshore was in the slings it weighed a meager 90,000 lbs. I spend a lot of time cruising at 14 knots which is just over the hump, comfortable, Cat display says I'm at about 70% power and I'm burning about 24 gallons a side. This was life changing coming from 1080 hp Detroit's burning well over 100 gallons an hour and not really going much faster. To my delight when I backed down to 1200 RPM I literally use almost nothing (like Honda Accord fuel economy) and still get a solid stabilized 10 knot ride. You will absolutely love that boat, It does most things extremely well. Engine room could be a little bigger but still very well laid out and these guys build a very high quality boat with systems laid out sensibly enough that make it super easy to run the boat well with just my wife and I. As far as main engines I think you have two really solid choices, I love my Cats but I wouldn't wait 6 months for them. My neighbor has a Nordhaven with Dear John's that he really loves but in So Cal parts are a day away where as Cummins is 5 minutes away and open 6 days a week. You really can't go wrong either way. Good luck and enjoy your boat.

 

[sunchaser]

-I talked to Tony at Seaboard for quite awhile and he's familiar with the boat (the boat is in SoCal and I originally considered doing the project down there). Assuming I didn't want to drop way down in power, he was the first to fully recommend the QSC as the best Cummins solution.

Bingo!!

You may want to prepare a detailed work plan for the engine swap and bid it out to Tony, Anacortes (Tri or North Harbor) sites and Seattle (Hatton or Radke?) The best engine swap guys may not be the best cosmetic guys. I'd not recommend an under-power. The $$ savings would be surprisingly small and resale and boat performance harmed.