Springbok rebuild

seanak 43

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Sep 3, 2011
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I just bought my first boat. It's an aluminum 1975 14 foot Springbok Runabout with a 1997 Johnson 40 HP. When I tried it out on the lake it was very sluggish, boat ran very bow high, and didn't seem to be able to get up on plane. The motor revved fine with no load but seemed to bog or load up when in gear. I had hoped to run it for the summer before tearing into it but it is not acceptable as it is. The previous owner had replaced the floor with pressure treated plywood and the transom wood was replaced with a 2x4 and a 2x6 stacked on top of each other - also pressure treated. Then to accommodate the long shaft Johnson they then fabricated a 3 inch plywood extension on the top of the transom cap. I asked what was under the floor and he said "Oh the original pour in foam is still there." The day after I got home from the lake I pulled up a section of the deck and sure enough it was the original foam complete with 40 years worth of water. No wonder performance was awful. So it seems a full rebuild is in order. Thanks to the members of i-boats I have some idea how to proceed but I'm sure I'll have questions as I go along. Thanks in advance.
 

jbcurt00

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ASAP get all the preesure treated lumber out of the boat and dont use PT on the rebuild.

Good luck w your project

Welcome to iboats

How about some pix of your Springbok
 

seanak 43

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Sep 3, 2011
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PT floor out, doesn,t seem to have caused any corrosion yet. I haven't got to the multi piece transom yet, don't know what I will find behind it. I have pics of what I have done so far, will post as soon as I get that figured out.
 

gm280

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Jun 26, 2011
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It would be interesting to have weighed the hull before and after you remove both the PT lumber and soaked foam. It is amazing to see how heavy that foam can get when soaked. We removes foam out of our tri-hull and it was so heavy. I honestly couldn't believe that foam could weigh that much. You are probably remove a few hundred pounds or more. Post them pictures. If you keep the pictures under 500 KBs they should load up without issue. Mine load easily at 100KB or less. We love pictures on these forums. :thumb:
 

seanak 43

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Yes the weight would have been interesting. I would be tempted to put a seat back in and take it for a rip empty to see the difference in performance but the nearest lake is about an hour away. 3rd post so pictures to come.
 

seanak 43

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Transom pictures. Steel plate inside splashwell for reinforcement. Transom extension is 2- 3/4 ply and 1-1/2 inch ply. I don't know if it is actually glued into one solid piece. Motor is mounted too low, it will actually plow water into the boat at certain speeds. The splashwell drains are blocked by the 2 inch lumber and sealed with silicone on the skin so the water cannot escape. <iframe width="480" height="360" src="http://s1244.photobucket.com/user/seanak43/embed/story"></iframe> Detail of dimensional lumber transom core under Splashwell
 

seanak 43

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Capacity plate Manufacture Alum Goods.50HP Chip of orange paint lower left is the clue. Springboks of that vintage were painted orange.
 

seanak 43

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Sep 3, 2011
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On to the teardown. 1st piece of deck torn up. Yes we have water. Notice the vinyl floor, woodgrain kitchen lino. starboard side pw. Bilge pump wires hanging loose but it didn't matter, pump is seized. What's the fancy shotglass with the spiral down the centre? I'm guessing it's for checking for water in your gas. Drain channel ran down middle under the foam. looks like it could be zinc but it's probably corroded aluminum.
There's a footwell ahead of the main deck, then an aluminum fore deck at the bow. There's more foam under it so it has to come out. Riveted along the front, then 8 rivets through the hull on each side. Foredeck removed. I hated to open up holes in the hull but it had to be done.
 

seanak 43

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Sep 3, 2011
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Some construction details:

No stringers, instead it has 5 bulkheads and 4 ribs.

The front of the splashwell is a 3 1/2" wide x 3" c channel.
The front bulkhead is tied to the hull by the aluminum foredeck.
Single knee brace at the transom.
Seems to be a very strong design.
 

seanak 43

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Sep 3, 2011
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I'm wondering if I should run a stringer of 1 1/2 or 2'" aluminum angle down the centre. It could be one piece recessed into the bulkheads, or cut to fit and riveted from one bulkhead into the next. I guess the deck does the same thing, I'm thinking a centre stinger would just add some extra strength and support. I believe the deck would have been 1/2 inch from the factory, PO used 5/8" for his pressure treated.
 

seanak 43

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Seating:

Seating that came with the boat: 2 miss matched buckets on 7 inch fixed pedestals.
Home built bench and storage, more treated wood. I never had the back seat in because I knew the back end was already way too heavy.
The open design was very roomy for a 14 footer. My plans are mainly for a fishing boat, usually solo, but I would also like to be able to carry 4 people if the need arises. I'm thinking one fixed helm seat, a swivel co-pilots seat, and either a bench/storage unit at the back or 2 removable pedestals. I'll have lots of time to decide on that.
 

seanak 43

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It would be interesting to have weighed the hull before and after you remove both the PT lumber and soaked foam. It is amazing to see how heavy that foam can get when soaked. We removes foam out of our tri-hull and it was so heavy. I honestly couldn't believe that foam could weigh that much. You are probably remove a few hundred pounds or more. Post them pictures. If you keep the pictures under 500 KBs they should load up without issue. Mine load easily at 100KB or less. We love pictures on these forums. :thumb:

10 large bags of foam @ about 20 lbs per bag, about 4 inches of standing water= about 18 cubic feet@ 8.3 lbs/cu.ft, and 48 sq feet wet plywood.... I'll call it 400 lbs.
 

gm280

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10 large bags of foam @ about 20 lbs per bag, about 4 inches of standing water= about 18 cubic feet@ 8.3 lbs/cu.ft, and 48 sq feet wet plywood.... I'll call it 400 lbs.

Well you just solved you sluggish motor issues now. :thumb:
 

seanak 43

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Well you just solved you sluggish motor issues now. :thumb:

I know. The Johnson 40 should be lots big enough for this little boat. I'm sure there will be a few issues when I get it back together but they should be small. I know nothing about boats or outboards but I look forward to learning. I've picked up a lot from the Starcraft guys by reading their rebuilds and decided to start a forum on something completely different. Springboks are old Canadian classics and deserve to live on
 

82rude

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May 8, 2012
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GM280my old boat gained 900 lbs.as weighed at dump scales.Soaked foam can weight a heck of a lot and cause all sorts of running problems just like the posters.
 

scoutabout

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Oct 14, 2006
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....Springboks are old Canadian classics and deserve to live on

Welcome and good luck with the rebuild! We've got a '72 14 footer that's been in the family since new.

Here's a pic of my son running a '56 Johnson 10hp on it. Goes at a respectable clip. Yours should do very well with that nice 40 - even with the extra weight of decks, floors, windshield etc our narrower open model doesn't have.

I've replaced the transom wood insert which crumbled away years ago but the family won't let me paint it! They say they like the look of her old and scuffed - shows she's lived a long life! LOL

image.png
 
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seanak 43

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Sep 3, 2011
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After more than a week of being too busy I got to do some work on the boat today. Motor has to come off so that means building a motor stand and an A-frame to lift it. I used a cable puller, you know the ones that say "Don,t use for vertical lift." Puller is rated for 2200 lbs pull, motor weighs 140 lbs, It worked fine. Disclaimer: Do this at your own risk. I watched everything carefully and was ready to stop at any indication of something wrong.
 

Woodonglass

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Dec 29, 2009
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Nice Gantry!!! Posting this for future reference...I got this at HarborFreight for $40 bucks on sale. worked great lifting my 85 hp Johnson Outboard. Screwed a 8" lag eye bolt into the garage Door Header.

image_24152.jpg
 

seanak 43

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Sep 3, 2011
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Motor off and on the stand it was time to continue with the teardown. In a previous post I noted the the transom was built in multiple pieces to extend it for a long shaft motor. the extension piece was plywood, 2 pieces 3/4 inch and what looked like 1 piece 1/2 inch. I couldn't tell if it was glued or not. this was held by 2 1/4 x 6 inch lag bolts, then a 1/8th inch steel plate bolted in by 8 bolts in total. The 3/4 pieces were glued, What I thought was 1/2 was 2 pieces of 1/4 ply, held only by the bolts.
 
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