bertram31.com

I Hall i'm Greg to New Caledonia
I ride a B28 with twin 6lpa

Welcome Greg!

Welcome aboard!

New Caledonia, I had to look that one up...quite a trip from my neck of the woods.
Great to see Bertram makes its presence there too.

Boat looks great, thanks for sharing pictures.

Boat gets used to Cruise, dive, fish or socialize? or quite possible its non of my business.

You found a great place for questions to be answered with a great group of guys.
Chime in when you can.

Welcome again,


Carl

Welcome Greg; love the boat and love the Yanmars (I had them in my 31). You will be right at home on this website. Thanks for posting the photos; please share some performance specs: cruising speed, etc.

Welcome. Very cool. Please post more pics of New Caledonia (and your boat).

Welcome

Nice looking 28. New Caledonia, not many of us are going to get over that way. Let us know what it is like. We all love Pictures of far away destinations. Especially warm ones.

Welcome Greg,

What's the trick to fit these yanmars into the 28? From the pics I see that you (or some previous owner) somehow lowered the stringers...is that so?
Thanks.

Yannis my friend has them in his 28. I believe they are 4 cylindar.

6 lpa 4 cylinder?
My search tells 315 hp...unless I didnt type correctly.
I thought my 240's were the biggest one could fit in there!

Yannis

I will double check with him when he gets back from Florida.

Tony,

If you cut the stringers to accomodate a bigger engine you may compromise the boat's structural integrity.
The way I see those pics this is what happened, but then again, I may be wrong as the pics are not so clear.

Yannis and others,

Those are definitely 6LPAs and are 6 cylinders (look at the 6 injector lines).
The hull stringers have not been cut. They are not visible in the pictures as they are covered with a structure that has been built to fit these engines.
Much like the original engine mounts.

Also, remember that Bertram built a number of B28 with 6 cylinder Volvos installed in the factory. These boats have a significantly different, bigger, engine compartment, and can accommodate the 6 cylinder motors. I would guess that this is one of those boats.

To get a better look at the hull stringers and how my boat was modified for the 4LHAs go here.

https://www.sbmar.com/repower-projects/ ... board-way/

We simply removed the wood engine supports, which were bolted to the hull stringers and laminated to the bulkhead. Then re-enforced the entire engine room (glass).

I would guess that Greg's boat is one of he ones originally fitted with Volvos.

Bill

Bill,

These stringers look like they're cut down to hull. I dont get the "structure" part.
Again, let the man explain.

315's in a 28? How?

Hi My B28 is an Australian version "Caribbean Bertram 28"

I just bought the boat 3 months ago and already 60 hours of navigation,

Originally the boat had 2 Mercuiser 170 hp and the previous owner changed the engines in 2006 by a professional

I reassure you the hull stingers did not have to modify, just to adapt new suport engine (soon I will make you photos of the work realize)

My numbers is: 2800 @ 21.5 / 22 kts 3000 @ 23.8/24 Kts and Wot 31.8 Kts at 3600



With a 4 blades 17x21 and Hurt 1.56

Next month new botom paint and I think the numbers will be still better

I go through a translator because I speak little english

Greg, thanks.
Whats your native language?

I am French and live in New Caledonia for 7 years

I came here to live because I am passionate about fishing

Yannis,

A couple of B28s on this site with 6 cylinder motors.
SteveZ has/had a B28 with 6BT Cummins, which I believe was repower from original 6 cylinder Volvos.
RAWicklund has/had a B28 with factory installed 6 cylinder Volvo KAMD42.
Again, these boats have longer and maybe taller engine compartments than our models.

Bill

Now that is fishing.

Bill,

I didnt say anything about 6 cylinders. I said specifically about the yanmar 6lpa which is 315hp and is so tall that, i thought, couldn't fit. The volvo is 230 hp.
But since Greg says all is well, then its OK with me too.
As you're saying, perhaps the Australian 28 is modified, so it can fit those motors.
But still, this boat should be a speed demon with 315's, the rev/speed numbers Greg is providing are similar to my numbers with 240's. I too hit 31 knots at wot and cruise at 24 knots with 3000rpm's. With 20% less motors. Strange.

Yannis,
I keep talking about 6 cylinder motors because the key to fitting them into a B28 is the length of the engine compartment.
There is plenty of width. Height can also be a problem but again, Bertram made these modification when they put the 6 cylinder motors in the boat.
They are quite different that what you and I have. Look up pictures of SteveZ boat with Cummins 6BTs (same size as the 370 HP 6BTAs except for the afte rcooler). They are way bigger than the Yanmar 6LPAs.

Greg,
Which 6LPAs do you have 6LPA-STE(P) or 6LPA-DTE(P)?

Bill

Hi Bill and Yannis

My Yanmar is 6LPAM-STP " why the M ?????"



I also noticed that I had the same number as the 240 'that comes from the transmission ?? or the propeller ?? , the person who remotoriser this 28 advises me to change the proleller for Radice 19x22 when do you think?

Greg,
Yanmar spec for your motors is that they should turn an honest 3950-4050 RPM at WOT and fully loaded.
Adjust the pitch in your props to obtain these numbers. if you have Yanmar tachometers be sure to check their accuracy with a photo tach.
Yanmar tachs are almost always not accurate.
Nice looking boat.
Sounds like you are having a lot of fun with it.
Bill

Bill, thanks.

Greg,

Could you possibly take a few close up pics of your bimini's metal frame, more specifically where the vertical supports meet the bridge? I wish to change my whole bimini structure and this one seems very simple and practical, have you tried it in bad weather to see if it's sturdy enough?
Thanks.

Hello everyone

Here is some picture of T top

Greg, thank you.

That looks like a nice top.

Tony,

Do you think this goes thru Bertram weather?
Or it goes up and down? I'll be having 2 big solars up there; it has to be very stable with Aegean winds.

Yannis

Unless the cover material is rigid it will move in the wind. Probably bellow. Plus if canvas , sunbrella ect it will actually be too soft and would not support any weight. The frame would need to be designed to support the dollar panels.

The guy in my yard took measurements from my boat and created a rigid bimini top for another 28 (foam core covered in glass), which is beautiful because it is concave exactly as it should be (he used the exact concavity of the bridge floor that he transferred to the bimini) and it is not too bulky nor too big - ideal for my boat.

Of course, there has to be a tube frame so I thought Greg's one is simple and not too crowded with diagonals and extra supports etc that would render it heavy.
So, inside that rigid bimini top he incorporates (during the foam cutting procedure) a couple of wooden beams that he subsequently covers with the glass layers. On those beams (that are positioned exactly where you want them to be, according to the pannels' fixing dimensions) you secure the solars with through bolts.

The only thing is that if I'm to do all this, I'll have to first demolish the existing structure, and while I'm at it, remake the seats and everything else up on the bridge, a task that is so complicated that I may just sit and dream of nice rigid biminis for the moment!!!

PS: In my current configuration, my 2 solar pannels sit on a SS frame that is constructed over and above the sunbrella bimini. There is a gap of about 3-4 cm in between, to allow for the sunbrella to move but also make so that there is a necessary air drought to cool the pannels. The pannels produce more electricity when their temp is kept the lowest possible!

Yannis

Sounds like you have it figured out. I would run the current set up until you are comfortable with the. Panels you currently have. Then in a year or three you can consider some upgraded.

Like so. The flood lights on top are not mine!