bilge draining in old runabouts

[Frank Mehaffey]

I was just looking at the discussion about limber holes on a sailboat.It brought to mind a design problem!?? on a Cruisers 18' lapstrake/plywood runabout I am starting to work on. The sides of the boat are traditional laps, no problems there. But the bottom of the boat is a relatively flat piece of 3/8' plywood, with the ribs attached from the sides of the lapstrakes to the plywood, to the keelsom. There is no way for water to get to the back of the boat, where the bilge pump is, unless it fills up one, and flows to the next, fills that up, etc.etc.to the back. I have serious misgivings with only 3/8' as the thickness of my bottom, and am considering doubling up the bottom, epoxy and new fastenings into the ribs. But I keep coming back to where does the water go????on the inside. One option for me is to trust in the great god WEST SYSTEM, and put 2-3 coats on the inside plywood and ribs, up to where the plywood meets the lapstrake. It seems to me that some builders back then, had some beautiful hull designs, and skimped on the strength and reinforcement factor on some of these boats. The Lyman and Thompson hulls, to me, seem to be the best in strength and longevity, but it seems that even on some well built runabouts, the bottom of the hull could have been overbuilt just a little more. Anyway, does anybody have any ideas (not involving sponges) for getting the water back. Someone even told me to bring the boat to one of those places that puts the urathane truck bed liner spray on the flat ply bottom, on the inside, to the water line!

[Andrew Craig-Bennett]

I know nothing about runabouts. But it seems to me that a pair of limber holes each side of the keelson at each frame would not significantly weaken the hull, and would solve the problem, since "g", in terms of the boat accelerating and then sitting on the plane, will send the water aft through them to the pump suction.

[Andreas Jordahl Rhude]

The Thompson and Cruisers, Inc. hulls were basically the same design and same construction materials. Makes sense since they were both owned and operated by Thompson family members.

Are you sure there is not a slight gap between the end of the rib and the keelson so the water can flow thru? The end of the rib should be tapered to create a small gap between it and the bottom hull planking. It's probably filled up with gunk. Don't go and pour more "stuff" in there are really clog it up.

Have you visited www.thompsondockside.com (http://www.thompsondockside.com) yet? This is the website for Thompson and all her various spin-offs inlcuding Cruisers, Inc. The second annual THOMPSON ANTIQUE & CLASSIC BOAT RALLY takes place August 9-11 at Marinette, Wisconsin, about 20 miles from Oconto (home of Cruisers). The Rally is for Thompson, Cruisers, T & T Boats, Thompson of New York, Thompson Royal-Craft, Grady-White Boats, etc... Last year we had 61 boats and canoes on display, including ten or more Cruisers'.

[Andreas Jordahl Rhude]

DO NOT put truck bed liner spray junk in the bilge. You are just asking for MAJOR trouble down the road.

Keep the bilge varnsihed like as she came from the factory or use a marine bilge paint. If you decide to piant, you'll probably have to strip off the existing varnish to make the paint properly adhere.

[Paul H. Morris]

I just this week-end finished a complete restoration of a 1963 Carver lap-strake open runabout of exactly the construction your Cruisers is. On this boat, the very first cleaning operation we did on the inside of the hull once we rolled her back upright is to clean the limber holes that are down next to the keelson. We used gardenhose, shop-vac (wet pickup), prodding wires, and compressed air. I don't think the previous two owners even knew they were there,-THEY WERE PLUGGED SOLID! ! Now a quart of water poured in next to the keelson can get to the stern and the drain or bilge pump in about 40 soconds.
The current owner was amazed and swears he'll check/clean them each fall at lay-up.
I have suspected that on production boats like these, some of the debris that is down there was there right from the day it left the manufacturer. Good Luck Paul