B25 '68 advice

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beachbum
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B25 '68 advice

Post by beachbum »

Dear all,

Long time lurker but finally looking at purchasing a B25 Sportfisherman 1968 build.

Got my eyes on one with a single Cummins Mercruiser (VM) 4.2l diesel, 320hp, 500 hours, from 2007. I'm yet to visit the boat (I'm from the UK but based in Italy, boat is in France). It's s mess judging by the photos, been used for fishing exclusively for the last few years.

My full time job is a superyacht skipper (Pershing 108) so most, if not all, jobs I would be expecting to perform myself.

However after researching in depth, I have some questions.

1) The fuel tanks in these models - what to look out for? This is my biggest concern as, from what I've read, they are a nightmare to access.
2) This engine - I'm getting very mixed reviews - positive and negative (had a good look on boatdiesel.com and asked around locally). Spares and servicing won't be an issue for me as VM are Italian. Anyone has any experience?
3) And rough top speed? I'm being told 28knots is WOT which seems a little slow considering the size. But 20 knot cruise sipping 25 lph seems more than acceptable.
4) Boat is kept in the water 10-11 months a year. Osmosis issues ever reported on this model / age hull?

Many thanks!
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CamB25
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Re: B25 '68 advice

Post by CamB25 »

Welcome! Sounds like a customized B25. Can't really say much without seeing it. Can you share some pictures?
1963 Bertram 25
1973 Boston Whaler 13 - sold!
1998 Scout 172 SF - beach taxi
beachbum
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Re: B25 '68 advice

Post by beachbum »

Hey Cam - thanks - this is her:

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Yannis
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Re: B25 '68 advice

Post by Yannis »

Beachbum,

Looks beautiful and in good condition.
Don't know about engine condition or osmosis, but 25lph at 20 knots seems a little too low I think.

320hp X 80%cruising speed horses=256hp used
256 X 180gr/horse/hour=46lph

This is an all time classic calculation that dates back a few decades. There are most probably some important technological improvements in the per horse/per hour grammage in recent years, but 25lph still sounds too little to me.
Do you plan to move it to Italy by yourself?
1973 B28 FBC/2007 4LHA STP's - "Phantom Duck" - Hull "BER 00794 1172"
beachbum
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Re: B25 '68 advice

Post by beachbum »

Hey Yannis,

I have my doubts as to whether this engine is actually 320hp. When I go to see it, I have a list of the model numbers and respective hp so I can verify fairly quickly. I also thought it was a bit too low (consumption) to be true, to be honest. Then again, it's a litre every 2.5 mins at cruising (and it's on sterndrive) so maybe not out of the question?

My biggest concern, as I've said, is the fuel tanks.

Yep I suspect I will be moving it from France to Italy myself along the coast. I have about 200nm to do but won't ever venture more than about 5 miles offshore. The problem is the COVID restrictions. I am awaiting a quote to put it on a low loader but, at 3m wide, I suspect it'll be considered "Transport exceptionelle" so it'll be bloody expensive. The thought of jumping into a boat I don't properly know, with no spares and minimal tools and running it for 10 hours straight, doesn't thrill me!
Yannis
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Re: B25 '68 advice

Post by Yannis »

I agree, it wouldn't thrill me either.
I was once interested to buy a boat from the south of France and another one from Spain.
I wanted to bring it to Pireaus on a freighter...easier said than done.
I still have the list of paperwork needed, that has to be issued on the far end...let alone the cradle for which noone had the slightest dimensions...I ended up buying my 28 locally.
For you it’s closer so probably easier but this 200nm trip first time out on the sea doesn't thrill me at all!
Hey, stick it in that Pershing in the dinghy bay!

PS: As for the transport exceptionel, forget it, you need a cop on both ends for the whole trip. Who you have to pay in advance.
1973 B28 FBC/2007 4LHA STP's - "Phantom Duck" - Hull "BER 00794 1172"
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ktm_2000
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Re: B25 '68 advice

Post by ktm_2000 »

I'm not sure what happened to the boat in the past to convert it to a single, the hatch in front of the motor cover does not look stock, looks like something was done to redesign the deck there....

as for fuel tanks, the original bertram fuel tanks were fiberglass, when ethanol was introduced in to gasoline in the US, there were lots of problems with the ethanol eating the insides of the fuel tanks and leeching out resins which would burn up inside the gasoline motors eventually causing problems because the sticky goo would gum up engine valves.

I do not believe this condition existed for diesel fuel and that the tanks are still sound if used for diesel.
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Re: B25 '68 advice

Post by beachbum »

Thanks all

Ktm, I've been following your project, that's some serious work you've done, fair play to you.

Regarding the engine - it was reengined in 2017. I don't know much more than that at the moment. There is a livebait well in there too. In any case I'd want to stick an outboard bracket on there for a 9.9hp or something, just as a failsafe.
beachbum
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Re: B25 '68 advice

Post by beachbum »

Just following on from this - anyone know the height from keel to top of flybridge?
Yannis
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Re: B25 '68 advice

Post by Yannis »

I couldn't get ANY TWO identical dimensions from any two different sources.

Height, width (ok, the width you can manage), is it from the keel bottom? is it from the props? what is the distance between props to arrange for a cradle...etc etc.and then it's the borders!
I'm sure you ca find a good one in Italy, look in the ads or talk to a few guys on this board who live there.Or elsewhere in Europe.
I saw a beautiful Bertram Riva this summer...oh so beautiful, i'll post pics later.
1973 B28 FBC/2007 4LHA STP's - "Phantom Duck" - Hull "BER 00794 1172"
beachbum
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Re: B25 '68 advice

Post by beachbum »

Same here - all the dimensions I find are different!

All the local ones for sale are well out of my budget - the owner wants, well, considerably less for this one.

Anyway it looks like, all going well, I'll just be bringing it back by sea and taking a decent selection of tools / filters etc with me!
Yannis
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Re: B25 '68 advice

Post by Yannis »

I can come over to help, I'll bring my pfd, some this and that...
Then I can pay off by putting you up in my magnanimous 28! I know a few places in the Aegean that you'll appreciate...
1973 B28 FBC/2007 4LHA STP's - "Phantom Duck" - Hull "BER 00794 1172"
John Swick
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Re: B25 '68 advice

Post by John Swick »

Hi Beachbum,

My '62 B25 sport convertible w/a single gas 350hp mercruiser/b3 outdrive tops out on the GPS at just over 50mph.
Mind you it's alot lighter than the boat you're looking at (chines @ transom are +1" out of the water resting).
Even heavy with lots of gear and passengers my midrange #'s don't change much.
I've never tested top end #'s loaded up... I'm sure they'd be down abit.
That boat should be able to get to 40mph.
Could be a dirty bottom or turbo or injectors.
I'd check to see if the motor is getting all the way up to max rated rpm.
I don't think there's anything Cummins about that engine except the badging.
But your in the right spot for parts anyways.

Cockpit sole on that boat from the stern to the midship drop down is not OEM.
OEM sole had a big centre hatch with great fuel tank(s) accessibility.
They are a bitch to get out because of the very tight fit in the molded grid system, and whatever membrane they put down before tank installation turns into an adhesive over time.
I still have OEM fibreglass tanks in one of my gas boats, but I only use non-ethanol gasoline.
They would've had to reconfigure the transom and stringer grid in the motor bay for the repower.
Maybe the tanks were replaced then(?).
Looks like there is an inspection hatch there now, so that can be verified.
Regardless, it's major surgery to get at whatever tank is in there now.

If a poly-fibre boat sits in the water all the time and it isn't properly barrier coated, eventually it's going to blister.
So it's either been done, or will eventually need to be done.

Used boats are usually priced based on their condition.
So if it's priced well below the market value, there's a reason(s).
Maybe the broker/seller will be upfront about that, and maybe not.
A reputable marine surveyor should be able to clarify the situation for you.

Good luck,
John
1971 31' Bahia Mar hull# 316-1035
beachbum
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Re: B25 '68 advice

Post by beachbum »

Yannis - I've done the Aegean a few times - we ended up running for cover from the meltemi most of the time but the islands around Athens (Aegina etc) were also fantastic. Regarding the transport - I'm thinking of making an offer then when the offer is refused and a counter offer proposed (if we get that far...), saying ok but on the basis that they move the boat much closer to the Italian border, 80-100 miles from where I am.

John - Thanks very much for the advice. I've since learned that this owner has actually got a B31 already and just wants rid of his smaller one now. I'll be able to learn a lot more when I go to have a look at it, next week all being well. My colleague, coincidentally, used to work in the shipyard that the boat is based in now so I'll be bringing him with me.

Indeed all my research shows me that the engine is almost nothing to do with Cummins. 28 knots is about 32-33mph so yeah it might be dirty or underpropped. It was apparently subject to a "refit" in 2017, when they installed this engine so possibly tanks done then. We shall see! Thanks again
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Re: B25 '68 advice

Post by Yannis »

Beachbum,

There is an Italian site called yacht4web.
In there, there are right now around 10 Bertrams for sale, of which one 25 Riva.
Take a look and most of these boats are already in Italy.
1973 B28 FBC/2007 4LHA STP's - "Phantom Duck" - Hull "BER 00794 1172"
Ttownthomas
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Re: B25 '68 advice

Post by Ttownthomas »

What about those deck hatches outboard of the stringers? That also does not look stock I don't think. More evidence the deck has been re-done
beachbum
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Re: B25 '68 advice

Post by beachbum »

It's been modified a fair bit. The stbd side deck hatch is a live bait well. It's anything but original, this boat. Hull 254 - 1422.

I went to see it and we're negotiating at the moment. According to the owner, everything is in order. According to me, it is not - there is a lot of work to do on this boat.

The Bravo 2 leg has a very rusted steering arm which makes me highly suspicious (seal gone, possibly a new transom assembly required...). I am likely to purchase this boat but it'll need the engine lifting, leg removing and a fair bit of work doing, which I am pricing in. However I'm quite happy to do this as it' means I can put everything right immediately. Of course, I have asked our regular shipyard (that sorts out the Pershing 108 I work on) to be as friendly as possible so this has helped a lot.

Updates to follow...
beachbum
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Re: B25 '68 advice

Post by beachbum »

Now purchased..... :-D

Should arrive from France next week. There will be a lot of questions from me, I'm sure.
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John F.
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Re: B25 '68 advice

Post by John F. »

Congratulations.
1968 B20 Moppie - Hull # 201-937
1969 B31 FBC - Hull # 315-881 (sold)
1977 B31 FBC - Hull # BERG1652M77J (sold)
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Re: B25 '68 advice

Post by Tony Meola »

Congratulations. Good luck with her.
1975 FBC BERG1467-315
Yannis
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Re: B25 '68 advice

Post by Yannis »

Congratulations.
We may meet somewhere, sometime...
1973 B28 FBC/2007 4LHA STP's - "Phantom Duck" - Hull "BER 00794 1172"
beachbum
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Re: B25 '68 advice

Post by beachbum »

Thanks all.

Yannis - yep I suspect so! We might well be off to Greece & Turkey next season on the Pershing, hopefully before or after the bulk of the meltemi. My boss did enjoy Aigina a lot in 2014, sat stern to the rocks for days.
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ktm_2000
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Re: B25 '68 advice

Post by ktm_2000 »

I wish you good luck with your new Bertram. Please post lots of pics when you get her home.
beachbum
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Re: B25 '68 advice

Post by beachbum »

She arrived at the start of December and I put her straight into the yard. To be honest, she was a bit more of a state than I remember but as it's a quiet time of year for me, I was gagging to go.

Started off just generally tidying up - throwing away all the old cr*p on board, cleaning inside the cabin and making the jobs list. It was raining a lot around this period which really stopped me but in the mean time I cleaned and painted the bilges under the cabin floor with danboline.

Took off the leg (Bravo II) - this was in better condition than I was expecting despite the vegetation. Gimbal ring, bell housing and transom assembly all salvageable but it was leaking into the boat a bit. I thought this was through the steering pin seal which is a common problem (steering arm completely rusted). It wasn't, more on that later...

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Onto the engine...

Tonnes of rust all over the place
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So hooked the engine out and got to work. Dismounted Intercooler, heat exchanger, turbo, riser, wastegate and starter motor as well as a few other parts that connect all those parts together. Sanded, primed, painted. Did the lower half of the engine whilst I was at it.

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beachbum
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Re: B25 '68 advice

Post by beachbum »

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Gave the h/e a bath first:

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Taped up everything after sanding:

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Primer then painted:

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Last edited by beachbum on Feb 13th, '21, 19:02, edited 1 time in total.
beachbum
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Re: B25 '68 advice

Post by beachbum »

Turbo and riser couldn't be saved so new ones were ordered (took the turbo to a specialist who said that it was losing absolutely loads of boost and wouldn't have been doing much, vane was quite wobbly, corrosion all over the place):

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All removed parts ready to go back on:

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Last edited by beachbum on Feb 13th, '21, 19:03, edited 2 times in total.
beachbum
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Re: B25 '68 advice

Post by beachbum »

New riser really is a thing of beauty

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Then the finished product:

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On to the leg. The leak into the boat was actually caused by a hole in the top of the transom assembly, corrosion. As it was about 3 inches above the waterline, it was only when there was some wave action or the boat moving when at rest. I cut out the corroded part and will put the JR marine plate in (google it if interested, really good way of being able to access the steering arm bolt). Still need to add a grease nipple to be able to grease the steering pin & seal properly as it's really close to the waterline, so will constantly dry out.

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beachbum
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Re: B25 '68 advice

Post by beachbum »

Took 6 hours just to clean the bilge to a reasonable level then another 6 hours to degrease it totally, sand and paint. Notice the addition of a freshwater flush point!

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Next week, the engine should be going back in (new mounts & alignment bar just arrived). The sterndrive requires a new cone clutch which was nearly impossible to find (went out of production around 2005 but found a second hand one in good condition in the USA). Once installed, filled with oil and all bellows changed, it will go back on. Then it'll be antifoul and back in the water for sea trials.

After that, the electrical system will need totally overhauling!

Watch this space, more to come.
beachbum
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Re: B25 '68 advice

Post by beachbum »

Not quite there yet but a few more photos:

Engine going back in

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A few repairs, leg still to go on. Notice the stainless plate on the transom assembly, with a hole in and a grease fitting

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Leg back on, antifouled

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From the outside, there is very little difference. In fact she's probably a bit dirtier if anything!

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A few more jobs to sort out but should be launching next week.....
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Tommy
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Re: B25 '68 advice

Post by Tommy »

Great progress, Beach Bum; keep up the great work!
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Re: B25 '68 advice

Post by beachbum »

I won't lie, I was pretty nervous (not about the crane procedure but about leaks from the sterndrive / having forgotten something etc)

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Quite a disappointing 25 knots flat out though she'll sit at 20 knots very comfortably. There was a bit of swell so it was difficult to find the right trim. By the time I've trimmed her correctly, I reckon there is at least 1 or 2 more knots available!
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ktm_2000
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Re: B25 '68 advice

Post by ktm_2000 »

the speed seems a little slow based upon the HP you have, are you making the rated RPM for the motor?

the reason why I ask is that a buddy has a similar sized boat to my B25 and a 383hp mercruiser mated up to a Bravo II outdrive and his boat couldn't go all that fast and a lot of it was that he had too low of a pitch in his prop. In his case he could push well past the rated RPM of the motor and he chose to not swap the prop and live with the slower speed.

I think the bravo drives have different gear ratios in order to swing larger diameter props
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John F.
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Re: B25 '68 advice

Post by John F. »

Nice work and your boat looks great.
1968 B20 Moppie - Hull # 201-937
1969 B31 FBC - Hull # 315-881 (sold)
1977 B31 FBC - Hull # BERG1652M77J (sold)
beachbum
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Re: B25 '68 advice

Post by beachbum »

Rev counters on both helm positions don't work...on the flybridge it'll give a reading every now and then but it's one of the 101 things I need to do still.

The turbo whine is absolutely fantastic, when it was spooling up I was thinking, "jeez this thing is gonna fly" but I think you are right in that the prop isn't correctly specced or the gearset in the Bravo is wrong.

The gearshift, when I first bought the boat, was horrendous. Had to lead hard on the throttle to get her into gear. This lead me to stripping down the top half of the Bravo leg as I thought it was caused by the small indent ball, which can often get stuck or the spring corrodes. It wasn't, and the spring was fine, so I took the upper gearset apart and the cone clutch was on the way out big time. Further investigation revealed that part was NLA so I found a 2nd hand one in the US after a lot of looking, but it means the leg is from pre-1999. Gearshift is now pretty good but I'm sure the boat should be getting a better top speed.

When I sea trialed, we hit 21 knots and that was with a very dirty bottom and the old turbo (which I couldn't save so replaced), 4 people on board and about 3-4ft seas.
beachbum
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Re: B25 '68 advice

Post by beachbum »

John F. wrote: Mar 19th, '21, 15:56 Nice work and your boat looks great.
Thanks John.

My paint guy didn't manage to repair the chips and scratches in the hull, which was mildly annoying as he'd promised me he'd do it, but the boat is starting to come together slowly. The problem with working on a superyacht as the day job, is that you see everything through superyacht eyes. I still see her as a mess even if the enginebay is now sorted. A few days with the polisher and some rags will certainly help, plus some 2-part on the upper bench seat and siderails.

Does anyone have a .jpeg of the outline of a B25 Sport Fly? I'd like to get a few t-shirts made up, with the boat's outline on the back.
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DanielM
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Re: B25 '68 advice

Post by DanielM »

She looks nice. Good looking picture with her at rest by the dock.

Funny thing I didn’t even notice there were a couple other boats in the picture until I scrolled through the pictures a second time.
beachbum
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Re: B25 '68 advice

Post by beachbum »

Couple of extra questions:

Anyone know the fuel tank capacity? Single tank version. It certainly looks original.

I was told the fuel gauge was working when I purchased the boat. I stuck 30 litres in before doing a quick seatrial and the needle did move a tiny bit. However upon opening the tank to check (I was convinced the boat felt heavy and could almost 'feel' the sloshing of the fuel at faster speeds when turning), it turns out to be nearly full, 80% or so. Happy days!

Does anyone have a .jpg of the outline of a B25? I want to get a few t-shirts made up for people that have helped me along the way, thought it would be a nice touch to offer a t-shirt!
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ktm_2000
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Re: B25 '68 advice

Post by ktm_2000 »

Hi,

I don't have one of the sport fisherman, I'm guessing one exists. Here's one that covers the moppie and express

https://photos.app.goo.gl/itMw52T2UkCTLAJm9
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Re: B25 '68 advice

Post by mike ohlstein »

1968 boats has the smaller, 177 (?) gallon fuel tank. 1972 and later boats have 220 to 230 gallon tanks. Everything is build by hand, so they're all slightly different. Mine says it's 231.
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beachbum
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Re: B25 '68 advice

Post by beachbum »

Thanks mike & ktm

177 gallons (presume US gallons..) = 670 litres, which seems bloody massive for a 25fter to me!

I guess when there were 2 petrol engines pushing her along, that 670 litres went pretty quick
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ktm_2000
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Re: B25 '68 advice

Post by ktm_2000 »

I think Mike may have given you the B31 numbers, I doubt a B25 had much if anything over 100 gallons
Ttownthomas
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Re: B25 '68 advice

Post by Ttownthomas »

Original literature says 112 gallons. here is a snippet. PM me your email address and Ill send you the pdf of the owners manual.

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beachbum
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Re: B25 '68 advice

Post by beachbum »

Ttownthomas wrote: Apr 4th, '21, 01:48 Original literature says 112 gallons. here is a snippet. PM me your email address and Ill send you the pdf of the owners manual.
Thanks a lot! This site is awesome
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Re: B25 '68 advice

Post by mike ohlstein »

ktm_2000 wrote: Apr 1st, '21, 16:21 I think Mike may have given you the B31 numbers, I doubt a B25 had much if anything over 100 gallons
Yes...... sorry.
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Re: B25 '68 advice

Post by beachbum »

Does anyone have any info on the original toilet?

I assume trying to get anything for it is no longer possible. I disassembled it the other day and found a few parts that are beyond salvage. I tried using the flush only for a load of very reddy brown water to appear - luckily this was only rust infusion! I think it might require a complete new toilet. The small motor that powered the flush is good however.
beachbum
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Re: B25 '68 advice

Post by beachbum »

Just an update for anyone interested.

Had a good few days out on the B25 so far. Only 1 real issue - the engine stopped when coming off the plane recently. Checked everything I could think of on the engine itself, no issues. However upon opening the fuel tank, the pick up pipe was clogged, really clogged. Cleaned it all and cleaned as much of the tank as possible and she was up and running again.

This also added 200rpm onto WOT - now 4000rpm which is 100rpm more than the rated max.

Boat is still too slow (single 320hp diesel on Bravo 2) and I think the reason is either the gear ratio in the top part of the Bravo or the prop.

I have no idea where to begin with experimenting - half of me thinks that someone rigged it this way for a reason (fairly big, torquey engine for a sterndrive so make it spin faster with less stress....), the other half thinks that these Bravo 2's shouldn't have a problem dealing with pushing a 3.5ton boat a bit quicker. From what I can gather, the prop is the last part to change and first, the upper gearset should be altered. I don't even know if I have a 1.5:1, 1.62:1 etc...

She's beginning to look a bit neater. Want to give her a fresh coat of paint over the hull and any white area - torn between Alexseal and International (I'm going to avoid Awlgrip / Awlcraft as I don't think I'll get the best out of it).

Image
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Carl
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Re: B25 '68 advice

Post by Carl »

I'd agree the boat sounds slow for a 25', 320hp diesel boat. Where to start...get ALL your information and bring it to a good prop shop. You can ask us...but our opinions are like "arse"holes, everyone's got one including myself. However, I'd take our opinions here over much of what can be had for the same cost as the opinions given on any given dock.

So why not get started...with nothing to go on other than keeping the low-end unloaded, but wanting more speed I'd look into less pitch with more cup. I'd also look into shops or friends that may be willing to let you "borrow" a wheel.


The boat looks great...
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Re: B25 '68 advice

Post by beachbum »

Thanks Carl - a bit of Semco on the teak and a few hours polishing makes a huge difference.

Yep I'e considered having the prop cupped a bit. It's also got antifoul on it which must effect prop slip etc, really not that smooth a surface in contact with the water.

I'm not bothered about crazy speed at all, just a decent 28 knot top speed and the ability to cruise at 22 would do me fine.
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CamB25
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Joined: Nov 10th, '10, 08:11
Location: Wilmington, NC

Re: B25 '68 advice

Post by CamB25 »

From that picture, the boat looks heavy. Is the water covering the boot stripe forward to the superstructure or are my eyes not processing this image correctly. Hard chines appear to be significantly under the water line in the stern. Your making full RPM, so I'm not sure why you would adjust the gear ratio. You might increase the pitch of the prop an inch or 2 to stay at or just below max rpm, but that change will probably not get you to your desired top speed.

As a reference, my boat is light. Single outboard..maybe 600 lbs. with the bracket. 60 gallons of fuel. no people on board. Chines are out of the water at rest. If I place a 200 lb person on each swim platform, the chines just touch the water. It's light. With 300 hp and a 17pitch prop, I top out at 37 knots spinning 5700 rpm.

You might have all she's gonna give you.
1963 Bertram 25
1973 Boston Whaler 13 - sold!
1998 Scout 172 SF - beach taxi
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ktm_2000
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Joined: Jul 17th, '18, 14:46
Location: Central Mass

Re: B25 '68 advice

Post by ktm_2000 »

While I agree with Cam that your boat seems like it is on the heavier side, I do not agree with the concept that weight is the limiting factor on speed.

my rig which was definitely less weight with I/Os had 270hp and could easily hit 33kts and with that I was under propped and probably could have hit 35-36kts with correct props.

I have some experience with a Bravo setup with a buddy having a Fibfab 25' which is powered by a 383 stroker and Bravo 2 drive. Specs for the 383 are - Rated at 350hp @ crankshaft; torque specs: 390 lb/ft @4,200 rpm. His boat is less of a deep V than our Bertrams and is fairly heavy, probably in line with the weight of Beachbum's rig. His boat cruises at 3600 rpm at 22 kts and can top out about 28kts. I'm not sure what pitch prop he has on it but it can also slow troll wire line really well for stripers at 3kts so I am under the impression the previous owner who was a charter captain had setup the boat for that style fishing and really didn't care about top end.

I have not been on the boat when it was brought up to full throttle so I cannot comment on what the RPMs are and if it is definitively under propped but I am assuming that it is.

My recommendation would be the same as Carl's check with a prop shop and try different pitches.
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