B28 Repower Crusader 6.0 help

[Stephen Shadegg]

I have a 1973 Bertram 28 that has been in my family for 37 years. We love the boat and are proud Bertram owners.

However, it has come time to re-power and although I would love to drop a pair of 4LHA 240hp yanmars into it, if they were still in production, I just don’t see dumping 60k-80k into this little boat.

As a result, we will be re-powering with a pair of Crusader 6.0 375hp MPI’s and I'm looking for anyone who has done this re-power in a 28 or knows someone who has. There was a 1980 B28 for sale in Miami that had the 6.0’s but my attempts to get a hold of the owner have failed.

Because the boat is pre-1984 it does not have the raised engine decks, however, given the 6.0’s dimensions it should fit without modifying the decks.

Any feedback regarding this set up would be greatly appreciated.

Stephen

P.S. – This will be my first post and am glad I finally became a member.

[Yannis]

Hi Stephen,

I have a '73 B28 too, with 4LHA STP's.

Before I bought my boat in '13, I had considered many other options and while evaluating them I had asked for a cost estimate for a new 240 Yanmar to power a single motor fishing boat. This is the cost estimate a local Yanmar dealer had offered me at the time (2012). As you can see, although the text might be a bit incomprehensible to you, the bottom line for a new 240 Yammie was 14.415 €, which together with all peripherals (#2: Hydraulic reverse-1600€, #3: Shaft and prop-2.070 €, etc) totaled 18.646 €, plus VAT, plus installation.

All this,just to give you an indication of how much a re-power with the 240's would cost you. The equivalent cost for the 160's was 17.000 €, plus VAT, plus installation.
If I can be of further help, let me know.

[Yannis]

PS1: It is my impression that for the post '84 models, what was raised was the gunnels around the rear deck; I don't think that the motor boxes were raised or changed in any way compared to the previous model.
PS2: I have 2 American cousins (brothers) of Greek origin. One lives in San Diego, the other in Phoenix !

[scot]

Sorry I have no helpful response for you or insightful tips, but I will add;

As a result, we will be re-powering with a pair of Crusader 6.0 375hp MPI’s

The boat should be very fast by B28 standards. I assume the original power was twin 260hp small blocks. If you can fit them without issue that should make for a very nice power package in that boat IMHO.

[Preston Burrows]

Stephen,

Start with the easy thinking with respect to new engine fit!

What engines are in the boat now and can you compare their dimensions to the new Crusaders?

I re-powered my 1976 B28 FBC a number of years back [2004] and have copious notes/comparisons as to what would fit under the hatches which I would be happy to dust off and share.
I went with gas Chevy small blocks, 260hp, carbureted.

I believe the 1973 run of B28's are amongst those with the smallest engine deck/hatches?
[I believe there were either 3 or 4 engine deck/hatch variations dimensions wise over the B28's entire run 1971 - 1994?]

Another thought on new 6.0 Crusaders is their operating rpm with respect to propping and shafting and whether you would/could re-use your existing transmissions / shafts or go all new.

[Bruce]

Stephen,
A pair of 375hp engines in the 28 is a bit on the excess side considering they turn another 1000 rpm.
A pair of 275 to 310 works real good in the 5.7 liter.

[MarkD]

Stephen:

I went through a similar choice last year when I repowered. The MPI's, I was told would be a tight fit and I have a 1988 version. Bruce gave me some good advice and I ended up going with two new vortec carb'd 310 HP packages. I swapped my accessories and transmissions and it was very cost effective. I saw 2-2.5 knots faster at the same rpm.. And these motors can spin up to 5000 rpm vs. the 4400 on the old engines. All I had did with the running gear was put a small cup on the props. If you'd like more detail, send me a pm and I'll get right back to you. I think I was about $14k with rebuilt gears all in and that included new coolers and incidentals. I've been very happy so far.

Mark

[Preston Burrows]

MarkD,

What's your transmission ratio?

And, my friend, don't take this out of context, what is your shaft size?
1 1/4"? [If it makes you feel better my shaft size is 1 1/8"]

[Stephen Shadegg]

This all very helpful.

Transmission ratio is 2:1, with 1 1/4' shafts. Given the extra hp had planned on new trans, shafts, struts and props. Why did you go with the carb'd 5.7's and not MPI's

Also, what is interesting is the 5.7 MPI is L 41.6"x W 28.1" x 28.6" H were as the 6.0 is L 43.7"x W 27.8" x H 24.4". What I think is good about the 6.0 is it brings the boat up to today's standards. The boat also now holds 210 gal of fuel, 60 gal of water and 30 gal for bait tank so I would rather put low stress on high hp and not high stress of low hp motors.

At least that was my thinking.

[MarkD]

Preston:

I have the Borg warner 1.5:1 gears if I remember correctly. 1 1/4 shafts. I left everything stock when I upgraded the engines.

Mark

[Tooeez]

Welcome Stephen:
When I did my 28 2 years ago I did a lot of research on different engine options. I found a lot of negative posts about the 6.0, although I can't recall the sites they were on. I wound up replacing my original 228 Mercrusiers (305 blocks) with 5.7 vortecs with carbs, using my trannies (1.5:1), manifolds, etc. I went from an 18 kt cruise to 21+ kts at 1.2 to 1.5 mpg, all for about 14k total, which was the price I was quoted for one mpi Crusader. Fuel injection is nice, but I don't think it makes as big a difference in fuel consumption on a deep-v as it does on a modified-v boat.

[Carl]

Stephen,
A pair of 375hp engines in the 28 is a bit on the excess side considering they turn another 1000 rpm.
A pair of 275 to 310 works real good in the 5.7 liter.

You cannot get better information from a better source so thought worth a re-read.






In my opinion, carbs are real simple and for boats I love simple.

... whatever you decide is the perfect decision.

[Stephen Shadegg]

Stephen,
A pair of 375hp engines in the 28 is a bit on the excess side considering they turn another 1000 rpm.
A pair of 275 to 310 works real good in the 5.7 liter.

Based on Bruce and Carl's advice, it sounds like the 5.7 L is the best path to take.

With this in mined, is the 5.7 vortec that has referenced, simply a Chevy/GM motor that has been marinized with aftermarket manifolds, risers and heat exchangers/FWC? Or is it in reference to the MerCruiser 5.7 L or Crusader 5.7 L?

I appreciate everyone's advice and the Bertram31 forum is truly a great resource for Bertram owners.

Stephen

[Joe E]

Don't forget marine power, I repowered with a marine power EFI 5.7 350 ram jet in my 20 foot skippy and loved it. It sipped fuel and ran smooth as silk. Joe

http://marinepowerusa.com

[Tooeez]

The vortec is, I think, a 350 chevy truck engine. It has different heads and intake manifold than a standard 350, and a roller cam.

[MarkD]

It is also my understanding that whether Marine Power, Crusader 5.7, Mercruiser or other 5.7 engine package, they all use the base GM marinized vortec 5.7 block. Obviously, each makes their own modifications but I felt comfortable with two new 5.7 GM marine engines for my repower. So far so good.

[scot]

The difference between Vortec and non-Vortec engines is the head port, combustion chamber, manifold design, manifold to head bolt pattern and "maybe" pistons. The rest is basically the same. Roller cams showed up on just about all Chevy V8s & 4.3 V6s in the mid 90s, including the Vortec as stated. Some of the early Vortec engines that got the name stamped on them, but basically only had a different head port design. The later Vortec engines incorporated all of the above mentioned changes. Vortec heads will bolt onto earlier non-Vortec blocks, makes for a nice hp upgrade to an older block.

As noted ALL 5.7s are basic Chevy 350 small blocks. Truck, car, marine.. take your pick. Very early marine engines had some good stuff in them, i.e. forged cranks, forged vs cast pistons, HD rods, 4 bolt mains, etc. But about the only difference today is brass freeze plugs, stainless exhaust valves, 1.94 intake valves, 1.60 exhaust valves and stainless head gaskets, which are easy to add to automotive based engine. Main thing to watch is the head casting numbers when marinizing an automotive based 350. Chevy does offer a head that is typically found on marine engines, but it is not particularly thick and doesn't really flow much better than other high output heads. The same head is often also found on the GM Target Masters replacement engines. There are a lot of thin castings out there that should be avoided with smaller valves (a lot of truck engines have smaller valves).

I like the Pleasure Craft Marine (PCM) marinizing packages. Simple, inexpensive components that hold up very well, also easy to find replacement parts when needed.

[waggles02673]

Years ago I repowered my old B28 with Marinepower 5.7 325hp MPIs and the boat ran real nice. I had posted about it on the old board. I will see if I can find the numbers I was seeing after the repower.

Jon