The current issue of B&H has a front page shot of a B20 Moppie that belongs to Mack Boring and they just put a 6BY220Z Yanmar & outdrive in her....also they pretty much overhauled the whole boat, red paint, new windshield, etc. Article says they are going to use it as a demo for the 6BY series and take her to boat shows. So you guys toying with diesel-izing a B20 might want to go take a look at her.
Doug C, Harv and myself went for a ride on it at AC. Nice boat. She scooted rignt along, but she jumped at the dock when in and out of gear, and had a pretty high idle speed.
It was also at the NY boat show in January. Very pretty. I prefer a Volvo D-3 190 hp with it's Ocean series (graphite) Duoprop...but can afford neither. Walter
walterk wrote:It was also at the NY boat show in January. Very pretty. I prefer a Volvo D-3 190 hp with it's Ocean series (graphite) Duoprop...but can afford neither. Walter
Walter I think I remember a few guys on the B25 board talking about those props shearing. Am I remembering correctly?
To be perfectly honest, I hadn't heard that. My reports from some who put them in was excellent. They seem to be a perfect fit in terms of size and weight. The Yanmar/Bravo 3 combos needed a special external cooling setup to prevent the Bravo 3 unit from overheating. Didn't feel good about that.
I agree with Walter and as someone with 3 Volvo D3 160's, 1 in the B20 and 2 in the B25, I feel that I can speak from experience on this one. These engines are far and away the best choice for such a conversion. I've been in a boat powered by those 170 hp motors built under contract to one mfr for another, coupled to a drive not built specifically for said motor and can say they suck compared to the D3's. In one boat, 350 trouble-free, fuel-sipping beefy power hours over 3 seasons and in the other, only 15 similar hours in one season-Hey, I got a late start, what can I say? The idea that a coupled engine/gear set-up made sense to me and I can say that, in practice, it is an amazing deal...
That boat was at the Bertram Mid-Atlantic Rendezvous. The install looked clean and yes it is a BMW engine. Last year a 28 Bertram showed up with those motors. Mack Boring is demoing the boat; plus they are fishing a lot of tournaments in a sportfish boat. I forget the make.
The Bravo II HP's are used all the time up to 800HP in go fasts. The drive shower does help keep the upper bearings cool. Remember that they are out of the water and in the water all the time. Even with good throttling that is hard on outdrives. I wouldn't think that a B20 would stress them much.
The thing that bothers me about them is that those showers are an "after-fix". They burned up a lot of them before they figured that out. What they need is a Bravo four where the cooling is designed into the outdrive's cooling system rather than this add-on. Walter
