L-36 topics

L-36 List of Concerns

Dec., 2006, Survey Items for Concern, L-36 - Age About 50

The following are suggested areas for thorough examination, with recommendations for dealing with any problems discovered during the course of survey of the subject vessel class, built in Costa Mesa, California, only, from about l955 on. These are in no way intended to substitute for examinations, findings, and recommendations, which would otherwise be included in a normal survey, which could be considered additional work, and effect the survey cost. These should therefore be discussed beforehand, with the attending surveyor regarding any work felt to be beyond the scope of normal practice. As there is a high probability that most of the items described below may have been discovered, and dealt with in some fashion in the past, there is always the chance that, for whatever reason, the type of repair, workmanship, materials, and methods, and how much time may have past since, it may no longer be up to the task, or possibly never was, and therefore examination in the manner of a detective with forethought might be well considered, all in view of the suitability for the proposed use, and ultimate resale value of the vessel. There is much truth in the saying "Bargain boats turnout to be the most expensive in the long run".

1. Frame Fractures. There are about 70 bent white oak frames, all of which are subject to complete or partial fracturing in tension as the hull increases girth due to planking expansion. Fractures occur at one or more locations, multiple fracturing occurring in midship areas where there is maximum girth. Partial cracking starts at the planking side, usually in way of a fastening. Midship cracks can be as much as 1/4 inch; alternatively some frames may pull inwards away from their fastenings, creating gaps between the frames and the planking. Thorough examination requires plywood ceiling and water tank, and other internals/furnature removal, several in way of the ice box cabinetry can not be completely observed.

Recommendation: Partial or complete renewal, or sistering, of frames found to be fractured, scarphing partial renewals and/or sisters to extend at least six plank widths beyond fracture(s), using existing planking fastening holes, fastened as original on alternate planks. Discussion with the designer, recommended white or red oak laminated sisters, full or partial replacements, using epoxy adhesive, as well as epoxy adhesive between the frames and the hull planking upon installation.

2. Underwater Fastenings. Original hull fastenings are #10 x 1 4/4 " silicon bronze screws, which, after considerable time, the underwater areas are only held in place by the compaction of granulated wood fibers and products of bronze corrosion binding them together. Screws are driven in alternate planks, in alternate frames, and along the garboard, spaced 2 1/2 to 3 inches, garboard fasteners, driven into mahogany rather than oak, tend to be in relatively much better condition. Remove a dozen or so, enough to make a good evaluation frame fastening condition over a wide and random range, to determine extent of deterioration, and required work scope, should refastening be recommended. There are hundreds of these fastenings.

Recommendation: Depending on the evaluation of removed fastenings and estimating their remaining service life, complete underwater refastening may be recommended.

3. Chain Plate Bolting. Chain plates are bolted through the hull onto stand off frames with 1/4 inch bronze bolts. Over time the original bolts have been weakened by corrosion, and have sheared under sailing load, allowing the chain plate to pull up, with ultimate dangerous and expensive dismasting. These are simply tested by tightening (with a 7/16 in.) wrench.

Recommendation: TOTAL replacement if any nuts should break off in tightening.

4. a. Through Hulls, Seacocks. Original through hulls were flush/mushroom type, held on a backing block with a locknut and a bronze(?) gate valve.

Recommendation: Replace any deteriorated through hulls and fit with, bolted through the planking type, seacocks, where not previously fitted, on suitable backing blocks.

4.b. Some boats were not fitted with valves/seacocks on the cockpit drains, nor with crossing over drain connections/hoses.

Recommendation: Replace any deteriorated cockpit drain throughhulls and fit with new seacocks similar to 4.a. above, with crossing over drain hoses.

5. a. Floors and Floor Bolting. Floor to frame bolts originally fitted were 1/4 inch galvanized carriage bolts, which touched or came into close proximity to the bronze planking fastenings, rusting in bilgewater and causing electrolytic de-lignification of the frame heels in the midship section, and in some locations softening of the floor undersides. Examine all frame heels and floors for deterioration and rot.

Recommend: Replace or suitably treat and/or reinforce any areas of weakness found.

5. b. In the forward vee berth area beneath the water tank area and adjacent to the two bulkheads forward and aft of the tank, bronze angles were fitted to the bulkheads and keel substituting for floors. Over time, with pounding, the angle fastenings loosen up as do those attaching these bulkheads to their adjacent frames, causing ultimate weakness in the bow area, where pounding into the sea is most severe, particularly with a full water tank, say 400 lb.

Recommendation: Remove these two bronze angles, and fit suitable, about 1 1/2 in. mahogany floors similar to those adjacent, bronze bolted through the keel and fastened to the bulkheads/frames, and replaceing any questionable bulkhead to frame fastenings

6. a. Keel Bolts, Ballast and Deadwood. Ballast keelbolts should be tested by tightening, turning easily indicates breakage, usually found where the keel and floor meet. There are ten 5/8 inch non-ferrous bolts through floors and deadwood, and through the lead ballast. The after most eight are in pairs, their lower ends with nuts in counterbores in the lead, the forward most two, singles, in pockets, possibly at different lengths and port and/or starboard.

Recommendation: Should any broken bolts be found, all keel bolts should be removed and examined and any defective keel bolts should be replaced. It is quite possible that some bolts have been replaced in the past, hopefully with silicon bronze, or better monel.

Note: Some original keel bolts were of substandard material, i.e. brass, which can be determined by examination of the upper broken stub

6. b. There are either pairs or singles, of 1/2 inch galvanized bolts through deadwood only, their upper ends atop floors, their lower ends in counterbores in the fir deadwood, above the worm shoe. One or two of these forward of the forwardmost ballast keel bolt, and the remainder aft of the aftermost pair of ballast keel bolts. The condition of these galvanized bolts cannot be economically determined, but experience would indicate there is little no steel remaining within their midsections.

Recommendation: Fit two or three new 5/8 inch bronze deadwood bolts on or near centerline, in way of the first two pair of original bolts aft of the aftermost ballast keel bolts, the third (5/8 inch bronze also), from the underside of the engine space, (which could require temporary engine repositioning for access), offset, and angled slightly aft at the lower end, so as not to conflict with alignment of original bolts, terminating in counterbores at the underside of the fir deadwood. Keel bolt length is about 54 inches, except the two forwardmost ballast bolts in pockets, which are somewhat shorter

At this time it might be economical to consider replacement of the worm shoe and/or its fastenings when/if removed for fitting lower end nuts and washers in deadwood counterbores. The worm shoe is fastened to the deadwood with galvanized lag screws.

7. Mast Step Reinforcement. There is, on some boats a non ferrous metal reinforcing strap, overlapping and bolted to the lower ends (see No. 3, above) of the upper shroud chainplates, fixed to standoff frames port and starboard, spanning downward passing the underside of the mast step, directly below the mast heel. The standoff frames, the metal condition and the floor just aft of the strap should be thoroughly examined, the frames for deterioration and fastening integrity, the metal for corrosion, and the floor for cracking on centerline in way if the galvanized deadwood bolt (mentioned in No. 6. b. above).

Recommendation: If as found conditions warrant, replace frame, strap, and sister or replace floor.

8. Headsail Track, Toerail Fastenings. Headsail fairlead track is fastened through the toerail and deck into underdeck blocking with No. 14 x 2 1/2 screws, as are the toerail screw heads concealed by the track. Due to coincidental spacing, during building, some of these screws pass into frame head end grain, rather than the intended blocking, providing little strength in attachment, passing the loads of headsail sheets to the adjacent fasteners,

Recommendation: Carefully tighten up on each track fastening screw with a brace and large screw driver bit, and replace any that will not snug up with longer screws, alternatively with 1/4 x 4 inch flathead, cut thread, machine screws. (may be $8 a pop?)

9. Rudderpost Cove. The rudderstock is faired into the rudderpost in a lead sheet lined cove shape and captured and supported in place by two pair of gudgeon plate halves, riveted to either side. Thoroughly examine rudderpost, rudderstock, gudgeons, and lead lined cove area for signs of loosening, deterioration, or softening.

Recommendation: Repair, tighten up, or replace as necessary, any areas found to be unsatisfactory

10. Propeller Strut, Rudderstock Housing. Examine the area of propeller strut mounting area and rudder stock housing tube mounting plate, and packing gland arrangement. Fresh (rainwater) can seep down around the rudderstock/cockpit sole penetration and collect atop the keel in way of the rudder housing tube and strut mounting nuts, causing softening of the keel and loosening of these bolts. Temporary fuel tank repositioning may be required for thorough examination, and may be required for any repairs to the keel and bolting The rudderstock packing gland cap was originally a re-machined 1 1/2 inch bronze standard pipe cap, bored out to fit the 11/4 inch diameter bronze stock, and quite thin for this purpose. Replacement of this cap requires unshipping of the rudder and lowering the rudderstock below the cockpit sole for clearance. The tiller head fitting is a keyed machined fit to the stock with a stainless allen head locking screw on the port side, not visible until the tiller is removed.

Recommendation: Repair, reinforce, or renew any of the various elements in this area found to be unsatisfactory. Any repair in way of the cockpit sole penetration, might include raising the sole surface blocking immediately surrounding the penetration, to allow any standing water to drain through the cockpit drains rather than down alongside the stock.

11. Lifeline Stanchion Bases. Original lifeline stanchion bases were through bolted to under-deck plywood backing blocks, and screwed to the toe-rail. Over time this bolting arrangement loosens up, allowing fresh water leakage, softening, and weakening of these bases, and a safety hazard.

Recommendation: Remove stanchion base bolting, Fabricate and fit six suitable stainless or bronze backing plates to the underside of the backing blocks, and re-bolt bases in place, over bedding compound, using new bolting, as required, with through bolting replacing toe-rail screws, with nuts set in counter-bores, suitably plugged.

12. Engine 12 Volt Charging System. The original gasoline engine 12 volt charging system consisted of an engine driven generator with detached voltage regulator. This setup was grounded on the positive side, which arrangement was later determined to contribute to electrolysis problems.

Recommendation: If not changed previously, at the time of overhaul, re-powering etc., the positive ground voltage regulator should be replaced with a negative ground regulator and associated wiring reconnected in a manner to assure proper operation and charging in the negative ground configuration.

13. Wooden Mast, Spreaders and Boom, and Standing Rigging. Mast and Boom are glued up hollow box section spruce. For whatever reasons, stress, time, or fresh water intrusion, may cause cracking or rot. These spars should be thoroughly examined for signs of de-lamination at the glue lines, particularly at the truck, spreaders, gooseneck, house top, and in the forward end of the trough beneath the double-thread outhaul fitting where there is a 1/2 inch drain hole. The spreaders are fixed with a 1/8 inch thick bronze flatbar bracket, which only allows hinge movement of the spreader in the up-down direction, which over time in service, cracks at the right angle bends. All wire standing rigging should be examined, in particular the swaged terminal fittings at each end for corrosion, cracking, and poor workmanship i.e. "bananas". Turnbuckles should be clean and free to adjust for their full travel.

Recommendations: Should any de-lamination be found, the cause should be determined, which could involve removing one complete length panel for internal examination for possible internal blocking rot, or other cause. Once the cause of de-lamination is found and corrected, the joints should be properly cleaned and re-glued, and if no cause can be found other than stress and age, all delaminated areas should be routed and properly splined. Extensive spar woodwork should be entrusted to a qualified Spar maker. The 1/2 inch drain hole should be lined with a copper tube, properly set in bedding compound, to assure no water accumulation in the trough area. Any cracked or deteriorated spreader brackets should be replaced, possibly bent up of 3/16 inch flat stock. Wire rigging found to be stranded or have corroded or cracked terminals, or "bananas" should be replaced. Turnbuckles and toggle pins should be examined and turnbuckles turned through their full range of adjustment, or replaced, as should any questionable toggle pins.

14. Transom to Deck Joint Area, and Exhaust Through Hull Fitting

The main deck consists of standard 1/2" x 4' x 8' Douglass Fir marine plywood sheets, laid on and butted between deck beams and backed at each butt by a similarly fitted ply piece, at roughly the 8' spacing. Along the topsides, fitted atop the sheer plank, is a sort of covering board, the thickness of the plywood, bronze ring shank nailed to the end grain of the ply, filling the space between the sheer strake and the toe rail, and in effect sealing the end grain. The fiberglass deck covering is atop the ply/covering board, extending outboard past the toe rail and inboard under the cabin trunk. At the transom, which is made up of three pre bent and laminated layers of 1/4" mahogany faced marine ply, the deck extends aft, terminating about 3/4" forward of forward/inboard face of the transom, therefore, no covering board detail, here As the top of curved transom runs up about 1/2 " above the fiberglass protective covering, the end grain of the transom ply is uncovered/unprotected, and if the curved two piece taffrail/toe rail pieces if not tightly sealed to the upper surface of this end grain, which is very difficult over time, fresh water entry and subsequent rot/softening of this plywood, and the internals such as the transom frame and transom beam and after ends of the topside planking may occur, and eventually progress. Similar softening can also occur in and surrounding the area of the wood in way of the exhaust outlet through hull fitting, over time, due to temperature changes, vibration, and prolonged exposure to damp environmental elements.

Recommendation: Should any softening in the upper transom, transom frame, transom beam, topside planking be suspected/found by either removing the taffrail piece and by ice pick probing, and hammer sounding, from inside the lazarette. All decayed wood should be replaced in good fashion and prior to replacement of the taffrail pieces the new end grain should be thoroughly saturated with penetrating epoxy, and then the surface protected with regular epoxy and allowed to cure prior to the resetting of the taffrail pieces, on suitable bedding compound. Should the transom be desired to be finished bright, the outer surface of the transom may be routed out to the required depth, and overlaid with a thin mahogany hardwood marine ply veneer, properly fitted and similarly end grain sealed at all end grain edges. The topsides, which taper in coming aft, allow a properly fitted veneer to be popped into place and set in epoxy. At this time it might be desired to relocate the exhaust outlet through hull, lower down and out through the topside planking, which is much more tolerant to this type of outlet.

15. Engine Exhaust System

Originally a 2 or 4 cylinder auxiliary gasoline engine with a direct drive reverse gear was fitted. The exhaust system directed the exhaust aft via a short un-jacketed piping arrangement from the exhaust manifold to a straight run of bronze cooling water jacketed piping, running from the engine compartment to the lazarrette, thence upward through another unjacketed pipe to the inlet of a cooling water injected Maxim type internally baffled cast iron wet silencer, mounted just below the deckhead, and overboard through a section of hose to the through hull mounted at the lower portion of the transom. The path of the raw cooling water is from the engine cooling water outlet through hoses, to the engine compartment end of the jacketed section, and from the lazzarette end up and injected into the silencer to mix with the exhaust gas and overboard. Over time the baffling rusts and flakes, away plugging up the silencer outlet, and causing and allowing the cooling water to backflow, flooding into the exhaust manifold and into the cylinders through open exhaust valves, with the possibility of catastrophic engine failure/damage. Because of this, and other reasons, many gasoline engines have been replaced with Diesels of a similar horsepower.

Recommendation: Irrespective the original gasoline engine installation remains, or has been replaced with a Diesel, the water jacketed piping with water injected Maxum type silencer arrangement should be replaced with a water lift type system. Failure of the internal baffleling within the cast iron silencer will eventually allow the injected seawater to flood back to the engine. Given the long distance from the exhaust manifold to the transom and the location of the exhaust manifold at the level of the waterline, this calls for the "long" type system, having a larger capacity water lift muffler, in the capacity range of three gallons, to preclude flooding back to the engine after shut down and/or repeated failed starting attempts. The raw cooling water piping/hose from the engine to the water injected exhaust ell fitting should include a riser fitted with a vacuum breaker, located as high and close to centerline as possible, and in any event above the "sailing waterline", to preclude the possibility of the cooling water back siphoning into, and filling the water lift, and ultimately the engine. This can occur when the engine cooling seacock is left open, while sailing a long constantly heeled course. Within the limited space available, this can be done, by locating the water lift in the lowest forward area of the port cockpit locker, and the vented loop vacuum breaker as high as possible directly above, . Alternatively, the water lift can be located in the after part of the engine compartment, as low as possible, with the vented loop in the cockpit locker location. The exhaust hose aft of the water lift should loop as high as possible under the lazarette deckhead on centerline, to prevent back flooding from the sea.

16. Notes on Planking Seams.

Reportedly, by original owners, the Philippine mahogany strip planking, net about 1" x 1.5", beaded and coved and finished to about 7/8" x 1.33, was glued up with casein type waterproof (somewhat) adhesive up to about Hull No. twenty something, and thereafter, by request, with resorcinol glue. The earlier boats planks were originally edge nailed with 3' x 1/8" Evedure Anchorfast (ring shank silicon bronze) nails spaced ten inches, thusly each plank has a nail every eight inches, and a nail head every ten inches in line with the seams. Some boats earlier than about Hull 22 have experienced extensive glue line fracture when allowed to dry out when hauled for more than a very short time. In some cases the hull has been cold molded, partially or fully sheathed in figerglass or extensively splined. Any splining should be done with extreme care in view of the nail heads being quite close to the surface at the seams. Sometime after hull 21 the nailing schedule was (increased) changed to 4 x 3/16' Evedure Anchorfast every six inches, meaning that three planks were nailed every two inches. This increase meant that there was over twice the nail cross sectional strength, one half the spacing distance, and three planks being through nailed, nails penetrating and spanning two seams rather than just one.


The foregoing is from personal experience and/or observation and all work described under the Recommendations has been performed by the writer and have stood the test of time. These have all been required to maintain the vessel in a seaworthy condition, and have been the result of structural design deficiencies, construction corner cutting, and/or use of substandard materials. This is not to say that there are not better, faster, cheaper, or more expensive ways to correct these Recommendations. Every workman has different ways of approaching particular repairs, depending on experience ability and budget, and will make recommendations accordingly, acorn nuts on ss bolts instead of riveted copper stock(if it's good enough for Dennis Conner? NOT) for instance. The ultimate responsibility rests with the owner, who bears the cost, trusts the safety of his/her family and guests to the seaworthiness of the vessel, and will bear the rework cost, as a minimum, if any of the three above mentioned, Design, Corner cutting, and Substandard materials are not avoided. This may take some study, thought, forethought, and analysis, however.

There has been no input or recommendations whatsoever from any outside sources in any of the above, USCG, ABYC, Insurance Companies etc. BG 12/12/06

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