engine swap for Tollycraft 48

[sunchaser]

Hi..The 48 is a 1982 and the engines are ,671n models with 301 HP..I don't have the paperwork history yet for the detail on the rebuild.

Those engines, with good maintenance, should last for a long time then with that HP rating.

 

[Bradenvlp]

I repowered last year from 6v92 to JD 6090. I did need new gears. While I’m glad I did it and the result is great, $100k is about 1/2 of what I’d budget for this project if you are using a yard in my opinion.

 

[Bradenvlp]

I’ll add that when I quoted Cummins last year the remand were nominally less than new ($3500 rings a bell).

 

[Fish Tales]

As part of a restoration project I am considering a swap from Detroit 671n engines to something cleaner and quieter.The Cummins 5.9 series seems to be what most people suggest on misc sites and also Yanmars as an alternative. Cummins has what seems to be a good choice with remanufactured engines.I would appreciate any comments or advice on what HP to choose between 315 and 370.Lots of weight to push here. Thanks in advance.

I have a 48 Tolly which I love. My power is two 6BTA Cummins at 300 HP each. I have sea trialed at 18 knots. I am on a fixed income and therefore usually travel at 8 knots. I have plenty of power if needed.

 

[jungpeter]

Couple small points…

You can get windows from Bounty, but not really window. If you break one, the new ones won’t perfectly match. Not a problem when replacing all. By then once the window is out, I did not understand the comment that you might hit the remaining frame and need to buy a new one. When the window is out, it’s entirely out, no frame to run into.

If you Re power, it’s an easy job to replace fuel tanks while everything is out. Others have successfully removed tanks with engines installed. It’s tricky, but can be done.

If somebody ran ducting above the engine hatches, move it next to the fuel tanks. Ducting isn’t much to move anyway.

....

Hi Ghost.

I suspect you're commenting on my post #17? With all due respect, I don't sense you're being entirely objective here. In your first paragraph, you make reference to Bounty Marine in Annacortes. While I haven't purchased windows from Bounty Marine, and thus can't provide first hand information, I'm going out on a limb and suggesting that yes, Bounty Marine CAN custom make aluminum window frames for a 40+year old Tollycraft. But OEM? Not likely. They may well be superlative, custom, welded windows, but identical to OEM? Color me suspicious. So, should the original poster damage a window frame upon extraction, he'll be left either with a damaged OEM frame, or a nice, new frame that sticks out like a sore thumb. Unless, of course, he chooses to replace ALL the frames and windows to match. Just send $$.

And the likelihood of damage to the frame (particularly from attempts to extract the stainless screws from the aluminum frame), the glass, the exterior gel coated cabin side, or the teak interior veneer upon extraction of the salon and window frame approaches 100%. The windows have been in there 40 years. They WON'T want to come out! Not a job for the faint of heart, or shallow wallet.

"If you repower, it's an easy job to replace fuel tanks..." No, neither easy, nor inexpensive. Replacement tankage alone, not including labor to jerk the old ones out, install the new ones, replumb and reinsulate, etc. is high dollar. But in the original poster's (OP) case, if the salon floor and engines must come out anyway, now's the time. To come back at some later date and replace a now-leaking OEM fuel tank and assume it can be done without again removal of the engines (and commensurate dynamiting of the guts of the boat) simply doesn't bear contemplation.

Regarding the HVAC ducting, again, not an easy R&R. And ducting is the least of the overhead systems in the way of a Tolly 48 repower. While the DC battery cabling, fuel system, and water systems are below the engine room floor, HVAC, 110VAC, 12VDC, and fire systems run below the salon floor over both engines. It's NOT possible to simply "... move them out of the way." Much has to be cut and respliced post-install to return the boat to functionality. Like I said in post #17, I see dollars flying overboard in just this task alone.

Repower questions in the real world are impossible to answer in a definitive fashion, and certainly with a broad brush. There's simply too many variables. I do believe however, there's one universal repower truism here. BRING BIG MONEY. The OP's mileage will vary, for sure. But as much as I love and admire Tolly 48s, the OP is likely to spend WAY more money on a repower than any Tolly 48 will support, even in this nutso buyer's market.

Regards,

Pete

 

[utclmjmper]

No engines, including DDs, were designed to leak.. Sometimes it just takes time to track them down..>>>Dan

 

[IRENE]

Mufflers

Viking, Trojan International, and some Hatteras yachts has fairly quiet (by DD standards) exhaust back in the mid 80s to mid 90s. I have to believe some checking in those circles would reveal a solution for quieting the exhaust, if that is a goal. I ran a 50 Viking and 13M Trojan International, both 6-71 boats (and performers) that were not noisy.

Perhaps the respective owners groups, posting here, or posting at boatdiesel.com would shed some additional light on the matter.

You could execute a fantastic refit for 25% of the projected repower cost!

Best Wishes

 

[Comodave]

That is what I would do, take a good part of the engine repower budget and fix the hell out of the boat, then enjoy!

 

[ghost]

Hi Ghost.



I suspect you're commenting on my post #17? With all due respect, I don't sense you're being entirely objective here. In your first paragraph, you make reference to Bounty Marine in Annacortes. While I haven't purchased windows from Bounty Marine, and thus can't provide first hand information, I'm going out on a limb and suggesting that yes, Bounty Marine CAN custom make aluminum window frames for a 40+year old Tollycraft. But OEM? Not likely. They may well be superlative, custom, welded windows, but identical to OEM? Color me suspicious. So, should the original poster damage a window frame upon extraction, he'll be left either with a damaged OEM frame, or a nice, new frame that sticks out like a sore thumb. Unless, of course, he chooses to replace ALL the frames and windows to match. Just send $$.



And the likelihood of damage to the frame (particularly from attempts to extract the stainless screws from the aluminum frame), the glass, the exterior gel coated cabin side, or the teak interior veneer upon extraction of the salon and window frame approaches 100%. The windows have been in there 40 years. They WON'T want to come out! Not a job for the faint of heart, or shallow wallet.



"If you repower, it's an easy job to replace fuel tanks..." No, neither easy, nor inexpensive. Replacement tankage alone, not including labor to jerk the old ones out, install the new ones, replumb and reinsulate, etc. is high dollar. But in the original poster's (OP) case, if the salon floor and engines must come out anyway, now's the time. To come back at some later date and replace a now-leaking OEM fuel tank and assume it can be done without again removal of the engines (and commensurate dynamiting of the guts of the boat) simply doesn't bear contemplation.



Regarding the HVAC ducting, again, not an easy R&R. And ducting is the least of the overhead systems in the way of a Tolly 48 repower. While the DC battery cabling, fuel system, and water systems are below the engine room floor, HVAC, 110VAC, 12VDC, and fire systems run below the salon floor over both engines. It's NOT possible to simply "... move them out of the way." Much has to be cut and respliced post-install to return the boat to functionality. Like I said in post #17, I see dollars flying overboard in just this task alone.



Repower questions in the real world are impossible to answer in a definitive fashion, and certainly with a broad brush. There's simply too many variables. I do believe however, there's one universal repower truism here. BRING BIG MONEY. The OP's mileage will vary, for sure. But as much as I love and admire Tolly 48s, the OP is likely to spend WAY more money on a repower than any Tolly 48 will support, even in this nutso buyer's market.



Regards,



Pete

On the windows, not sure how you misinterpreted what I wrote, but I think we agree. New Bounty windows are gorgeous but won’t match the old identically. You do all at once if you do them. I’ve not found windows terribly difficult to remove, it does require a bit of patience, but they come out. In the scale of a typical boat project, window removal is not terribly difficult in my opinion, speaking from experience, I’ve had most of mine out to be re-sealed at some point. Get a helper for the big ones. Tape up the window frames if moving something in or out or even clamp some ply over the surfaces if you can’t work safe, this really should not be a huge liability for most r&r jobs, in my opinion.

As far as things running under engine hatches, all I can say is that’s not how the factory did it. The three large engine hatches can and do come right up, with the exception of the port side which requires a bit of dismantling of the seating. Getting access to the engines is relative good for this kind of vessel. I don’t like things plumbed over engine hatches. I’ve got an 8 foot I beam I’ve set up over the salon before so I can pull heavy engine parts with just myself if I need to. It’s bad enough pulling up the carpet. If I found somebody had run wiring, through engine hatches, I think I’d flip my lid. It doesn’t belong there in my opinion, plain and simple. If somebody screwed that up, fix it. Getting good meaningful access is high on my list.

Replacing tanks with engines removed, is fairly easy. That does not necessarily imply inexpensive, good tanks are costly, but at this age they are getting replaced at some point either way. If you own a 40 year old boat and don’t have budget set aside for tanks, well then bless your heart I guess. Engines out certainly turns a hard job into an easy one. No way I’d pull engines without doing the tanks at the same time. I don’t generally hire a lot of work, so my definition of easy is that I can do the job without learning a new skill or hurting my back. If it’s a big job, it simply takes a few weeks longer. I don’t work that fast and take frequent breaks. No big deal, I’m here at least a few days a week, all year long, hell I’m here now. Tomorrow I work remote for most of the day and during my lunch I’ll spray some gelcoat to get some holes in my bow deck filled in so I can mount a larger Plath Windlass I’ve had re-manufactured. Later I’ll finish the instal, of some stainless risers. The point is, this is literally how I spend my time. Some people gamble. I spent time and money on my boat, the rest I waste.

I guess if you want to say I’m not objective, you are welcome to your opinion. I’ve owned a 48 for the better part of two decades. There is little I’ve not investigated, pulled apart, renovated, or planned for as I fully intend to cruise this boat for another 20 years and making plans to make it happen. I love this boat. There is not anything I want to do that this boat can’t do for me. It was one of Tolly’s favorites too.

I’m sure there is a lot I take for granted and my definition of easy may not be yours. I’ve been around Tolly’s for many years, largely know how they were built and sometimes why. I was involved with the Tollycraft boating club for many years, spoke with Tolly at length on many occasions, gave him his 100th and final birthday party and personally delivered his ashes to the sea. I stay in close contact with others who share the same passions, not to mention former factory personnel. We like to dissect these boats, put ‘em back together and when we are not doing it, we sit around and spend time talking about it.

So while I’d be the last one to want to stop learning or think I don’t have new things to learn, I’d submit I do have some capacity to speak on a few items on a 48 Tolly and Tollycraft in general. That does not mean I’m the only person who knows anything, just that I carry some level of confidence in my opinions. Opinions largely formed by first hand experience on this boat or others.

I know my style is not always tailored to be sensitive to those who want to make or take things personnel. Sorry if you felt offended. I really take little joy in arguing, it just makes me tired and disinterested. If you still want to call names, be my guest, this will be my last reply anyway. Feel free to continue to share your opinion, as I’ve shared mine. I’m sure the OP will benefit from both.

Best of luck to you, Ghost out.

 

[Tollycrafter]

Good Morning all...One thing that I didn't mention in my original post is that the boat has been sitting on the hard for two and a half years untouched.In my experience with airplanes and boats low or no operation is the bad news.I hear that 671's can sit for years and start right up and run but I'm not so sure so asking for some advice on this issue.

 

[twistedtree]

Lots of good advice, and I think the key message is to really fully scope the project before pulling the trigger.


Details like how you will tie into the existing exhaust system? Do new custom risers need to be fabricated? Are the mufflers adequate, if the boat even has mufflers? Can you add better mufflers while still meeting the back pressure requirements, lift and drop heights, etc.?


Will the engine beds accept the new engine & mounts and result in an engine and gear that are perfectly aligned with the shaft, or will the beds need to be modified? Can you reuse the gear, or are you getting new gears? Can the new engine+gear assembly be located such that the existing shaft length is correct, or will you need a longer or shorter shaft? Will you need new props? Will the shaft diameter need to change given the new engine HP, gear ratio, and prop? The answer better be no or you are having new struts made, plus replacing the shaft log.


Will the new engine and gear work with your existing shift and throttle controls, and what adapters are needed? Or will you need to replace the shift and throttle controls with new? And what about engine stop/start and instrumentation? Will that have to be replaced and wiring harnesses pulled through the boat? Will you need to rebuild your dash to accept the new instruments or will you somehow else deal with holes and other remnants?


Are the thruhulls and strainers large enough for the new engine? What sort of blocking and cribbing will need to be built to get the engines out and then back in?


You don't want to be surprised by any of this as each will add $5k- $10k to the cost.


I completely sympathize with the mission. I would want to replace the DDs as well, not because of reliability, but because they are like teenagers - I don't what to smell them, hear them, or clean up after them. But I suspect the only way such a project would be viable is if you have the time and skills to do it yourself. Otherwise, at $150/hr +/- for all the labor, I think you would be much better off selling the Tolley and buying one that already has different motors. Or do as others have suggested and mitigate the DD downsides as best you can.

 

[Tollycrafter]

Thanks...Good advice.I appreciate it.

 

[sunchaser]

Good Morning all...One thing that I didn't mention in my original post is that the boat has been sitting on the hard for two and a half years untouched.In my experience with airplanes and boats low or no operation is the bad news.I hear that 671's can sit for years and start right up and run but I'm not so sure so asking for some advice on this issue.

TC
I likely missed it, do you currently own this vessel or are you looking at buying it?

 

[Tollycrafter]

One week away from finalizing purchase or walkaway.

 

[ranger58sb]

One week away from finalizing purchase or walkaway.

If you like everything else about the boat -- the features you'll have to deal with every day aboard -- keep in mind that alternative boats will come with whatever engines they come with.

And that could lead to quieter engines in a boat you might not like quite as much.

-Chris

 

[Slowmo]

Obviously lots of input on repower. As to noise, our Tollycraft 40 has the Cat 3208N engines installed. Despite heavy sound insulation both in the engine room and under the carpets (mass weighted vinyl under the carpet and cabinets) there is still plenty of noise. Part of the issue is that the mufflers aren't very effective. The FG exhaust pipes running through the after cabin transmit lots noise into that area. FG is a 'live' material that transmits noise. The FG can vibrate with exhaust pulses and excite other surfaces around them amplifying the noise. .

Regardless of what course you choose I'd invest in the best mufflers you can fit and put them as close to the engine as you can. I also agree with insulating the engine room and floors. If you ever remove the headliner I'd also take that opportunity to insulate the ceilings to eliminate reverberation.
.
As to getting parts including windows, there are many of these boats in the PNW and almost anything is available. I'd recommend the Tollyclub forum as well: https://www.facebook.com/groups/tollyclub. Lots of 48 owners there and I'm sure many would love to follow your repower. You will also find what other owners have done in terms of repower. For myself having been in the lubricant formulation business and thus a lot of exposure to OEMs all I'd add is the Cummins are very good engines as are Deere engines both with very good support networks.

 

[Cleanslate]

Save money, what's the rush? Pull the throttles back to 1600 rpm and run 10 or so knots. That will keep sound down also. Keep those beautiful mechanical 671s, they will out last any of the motors you are considering IMO and are way more reliable compared to modern diesels with all that ''electronic alarms , computers, shut down, EPA stuff.
Find a good DD mechanic to give them some good love. Keep up on regular maintenance on your DD and the will not leak oil. You've got to keep things snugged up. Vibration over time tends to loosen things up on DD and cause leaks.
Add some sound stuff where you can . I'm sure that will help. Along with a nice large rug or carpeting above on the sole.
I've had many on my boats over the years, 8v71s, 6v53s, now 471TIs. All great motors for me. 671s,IMO are the best of them all.
Repowers, as other have said are not so easy. Put that money into what you have got.

 

[Rico Adams]

Hi, my Tolly 48 came with Cummins installed. They are 6BTA 300 hp. Plenty of engine, 20 knots, and very happy with them. We cruise fairly slow so I would be just as happy with a lower hp.

 

[ronobrien]

Do you know the HP of your 671? They came in a wide range. The original Grey Marine 671 that I had in an earlier charter boat, had a whopping 168 HP.

Would probably be a good idea to determine what speed you plan to cruise at and how much HP is required.

Ted

This is a good point. The J&T 671 ran up to 650HP. But I don't think that this means you must stay with exactly what you have, but other considerations come into play such as drive gear, props & shafts, engine mount beds, you get the idea. Just increasing HP doesn't mean you will get long term service out of the vessel as a whole.

 

[Comodave]

We had a 46’ trawler with twin 6V53s in it. It was a bit noisy but it was a throaty sound not an annoying higher pitched sound. We loved the sound of the Detroits. But we still did some insulation for sound. One of the easy improvements we did was Soundown carpet underlayment. It was 2 pounds per square foot. If you have carpeting it is an easy way to add sound insulation.

 

[TEXTrawler]

Tollycrafter,

Is this the 48 that was advertised on Craigslist in the MD area?

If so, I was interested in the boat but upon a closer look noticed the bilges had noticeable waterline marks up fairly high in the bilges---some over mechanical and electrical items. I suspect that the bilges may have filled with rainwater at some point during its 2-year stint on the hard. For some this may not be a deal-breaker but it was for me.

You may already be aware of this and may have a survey that has already identified this issue.

I just wanted to chime in case it helps a fellow Trawler Enthusiast avoid some potential headaches.

Best of luck...

 

[soin2la]

One week away from finalizing purchase or walkaway.

That was a year ago Saturday and nothing since.

What's "the rest of the story"?