Calling Ian: Bertram 20 Help

[Tommy]

Ian,

I am "internet-challenged" and I want to get up and running on your Bertram 20 link on 25Bertram.com, but need help. It's time to repower the '69 Sportsman and I need the expertise from you and the others on that site. Give me your "tips for dummies" to get started.

Thanks,

Tommy

[In Memory Walter K]

What have you got in it now and have you changed your fuel tank yet?

[Tommy]

Walter,

I started a restoration on the boat about 7 years ago after Uncle Vic graciously helped my buy her down in Coon-ass land. I pumped the tank dry, pulled the engine and outdrive, and then got distracted and put her in mothballs. The engine is a Merc "188", which is a 20 year old 4 banger, with an Alpha Drive. I figured the engine didn't have much life left in her, and that it was a good time to sweeten the pot. My brother is taking over the project, so I'm just trying to get as much info that I can from you pros. He's thinking a V-6 in the 225 range might be a good package. Changing out the tank is one of the things on the list. The boat is in pretty much original condition, so we figure she is a good candidate for a repower. I know that Ian and Doug (up in Canada) know these boats inside and out, and that all you 31 guys are pros as well. Thanks for jumping in here!

Tommy

[Michael]

Tommy,
I have a B20 Sportsman. Was repowered several years ago with a small block V8, which is a tight fit. Boat is very stern heavy with this power package and I feel it does not perform well as the driving position is very far aft. Carried 20 gal of water in bow to help balance the boat. Think the V8 power works better in the Moppie or Bahia Mar, where driver weight isfurther forward.
Because of this I removed the V8 and my next choice was a V6, even though itis only about 100 pounds lighter. Problem you will have is that it will not fit without modifying the aft deck storage boxes. they need to be cut to give clearance for exhaust risers. So i never actually installed a V6. Actually I think that just about any modern engine will require that these boxes be modified except the V 8. Even the Volvo D 3 needs this modification. The D3 is the best as far as weight is concerned, but I have heard too many issues with it to consider it a viable option. I think the engine is good, it is the electronics that cause problems.
As I wanted to keep my boat original, I have put an old Merc striaght 6 back in, which was the original power when new. I know most would not do this, but I am mechanically minded and do not like the electronics that accompany virtually all new engine

[ianupton]

Tommy -

RussP manages the site. I'll have to search around for his email, but he can get you signed up.

I have never actually seen a Sportsman, so I would follow Michael's suggestions. There is a current sportsman thread going where a new 4.3 was put in. He didn;t mention anything about the rear deck boxes needing to be retrofitted though...

http://simplifying.net/phpbb/viewtopic. ... 09&start=0

I think from a $$ perspective a 4.3 V6 is about the best performance for the money package. Not much heavier than the original inline 6 but huge increase in performance.

As Michael noted, the weight distribution is further back on the Sportsman so weight is a consideration.

Another power option that is growing on me (although I'm not considering for my project) is outboard. If you are in saltwater an not dry stored, this might have real merit. If I were to go this route, I would not ad a bracket, because I think this throws off balance even more. I would cut the transom down and put in a 'splash well' where the large rear deck is. I actually thought about this for mine, but couldn't come to terms with hacking that much fiberglass off. I did trace it out in pencil though.

You alraedy know this, but be ready for a wet transom. In the pictures in the post above, it seems that the stringers are fully fiberglassed unlike the Bahia Mar and Moppies that I have seen. Foam is probably wet as well.

Plus side is that there are not any other 20 foot center consoles that will get the attention that she will.

Get ahold of Russ and put up some pictures of her.

Cheers!

Ian.

[ianupton]

Sorry... just re-read some of "Spike's" post. He did have to modify the storage boxes.

Ian.

[Michael]

Ian, the Sportsman being redone on the B25 site has had the storage boxes modified already as I beleive the engine that was in there before was a V6.

[ianupton]

Tommy -

Here is another sprotsman thread with a V8 repower.

http://simplifying.net/phpbb/viewtopic.php?t=365

Ian.

[Tommy]

Ian and Michael,

Great info; thanks to both of you. I think we're leaning towards the 4.3 V-6, but have not eliminated the possibility of going with the original in-line 6.

Ian, what is the ideal cruising RPM of the 4.3, and what cruising speed does it provide. Same question for you, Michael; what is your ideal RPM/cruise speed?

Thanks to all,

Tommy

[ianupton]

Tommy -

I'll take a stab, but I have not had a B20 in the water for some time and my old hull had the old straight six in her.

Here's a picture of Doug's vessel view:



If I recall, pretty linear. At 3000 rpm engine is loafing and you are going about 30 mph.

Ian.

[Tommy]

Thanks Ian,

30 MPH at 3000 RPM is excellent in my opinion.

By the way, what is it you do in that far-away land? Any Bertrams there?

Tommy

[Michael]

Tommy,
I haven't splashed it yet with the straight 6. But from Bertram advertising it was supposed to do about 39-40mph at WOT - I am sure testing done under ideal conditions. I would say realisitically WOT would be more like 36mph.
So my guess at cruise would be around 28mph

[boatnuts]

A few extra suggestions.
1. Widen the engine bay in the rear floor if you intend to use either a V6 or V8 (aprox 36" overall width)
2. Raise the drive cutout when you redo the transom. X plus 1'' will work welll.

I did both on my 24 Moppie and have been very satisfied with the results.