Bilge pump repair

I almost forgot about the manual bilge pump repair, it was done between test sails 1 and 2. I was at a party before Christmas and got talking about the Teria with Tony, when i mentioned that the bilge pump probably wasn't working (but we did have a bucket and big sponge) he looked at me aghast and said " you had better fix that soon!".

So one day I had a look at it. The pump is a whale gusher hand pump which is located at the aft end of the starboard quarter locker. An intake hose went down to the yachts bilge-sump below the companionway step. The outlet hose exited from a transom fitting.

Starboard locker with bilge pump. Porta-poti can stow here for day sails but now it's kept at the aft end clear of the pump handle.

Our garden hose got plenty of water into the bilge sump but nothing happened when the pump handle was moved, no suction or water flow. So everything was removed from the locker and the pump was unbolted from the bulkhead.

Whale pump. Intake and elbow on lower left, the outlet goes to the right.

A 90 degree angle in the intake hose was occupied by a very rusty galvanized pipe fitting that shouldn't be in the saltiest parts of a boat in the first place, so removed it and replaced it with a  25 mm low pressure plastic angle from the hardware store for $1.50.

The pump still wouldn't work so my 8 y.o. daughter and i pulled the pump body apart. We found allot of debris under the valve seats, so cleaned it and reassembled. The pump worked well in the kids pool test. So it went back into position in the boat, we put the bolts back in - It's a 2 person job one for the inside nuts and another for the outside bolts. It worked a few pumps then stopped again, so open the pump on the bulkhead and same thing, full of debris which must have come from the sump.

The sump was full of black muck and debris which was getting sucked up.  I don't think anyone had cleaned out  the sump for a very long time. So this was cleaned out though-roughly. Then the intakes hose was cut off at 45 degrees on the end so it wouldn't suck stuff up as easily.  It wasn't long before the pump was moving garden hose water out as fast as it came in. 

Job done for now, but may have to get a strainer cage on the intake.

Shake down cruise # 2 - Ross River to Magnetic Island

The Teria was back on the road again on the 24th December, she already towed better with the trailer modifications. 

I arrived at the coast Guard ramp in Townsville about 9 am on 30th December but it was soon apparent that all the trailer spaces were already full.  

Had a chat with the coast guard officer on duty, the boat-trailer car park was filled at about 4.30 AM by recreational fishermen. It was the annual Christmas and New Year holiday plus the weather forecast was for light winds and flat seas - a perfect combination for a packed-out boat park. In desperation some boaters had parked on the councils grass nature strips, only to risk getting slapped with a $50 fine from the council.  The Port Authority runs the Coast guard ramps and boat trailer-park but the city council is responsible for all the surrounding nature strips etc. The ironic thing was cars without trailers or even tow-bars were allowed to take up valuable boat-trailer parking space, counted at least 5 solo cars there and it's still legal to do this on weekdays. The nearby casino car parks could have accommodated these solo cars who don't pay annual boat or trailer registration fees (around $400 pa). Meanwhile some guys religiously paying their rego fees are also paying parking fines for going on the grass,  I hope the authorities get together and sort it out one day soon.

It was suggested by the coast guard officer that we try the Barnicle street ramp at Ross River, so once my crew Ricky arrived we headed over there and found it had plenty of spaces available. It's run by the Townsville city council and there were upgrades and expansions done in recent years. It's a relatively quiet ramp , possibly because it's about 2 km to the Ross river mouth and an extra 1 km to Magnetic Island. However, the big deterrent for all masted vessels  is the new low-slung port access bridge over the river entrance, which has a low clearance of only 6.5 m which is not even enough for a trailer sailer. The Port Authority built a new harbor to seaward of the bridge for the prawn trawler fleet and Ross Haven ship yard  within the new port reclamation area. Townsville based Yachts now have to moor in the marinas or anchor in the more exposed  break wall near the casino. There was a proposal a couple of years ago, for a river break-wall seaward of the bridge and pile moorings for yachts too but this may have not been approved.

Fortunately we have a tabernacled mast and I hoped that it could be possible to motor out and raise the mast to seaward of the low bridge. Ricky was an experienced catamaran sailer and fisherman having owned two Cobra 16 cats and a 14 foot runabout, and the weather was good, so felt confident we could try the unusual sailing ground of Ross River.

We launched with only a few big pushes this time and tied up at the floating pontoon.

Mast down at the floating pontoon on Ross River

Then motored past the nearly deserted pile moorings, inhabited by a few motor launches and several yachts trapped in there until they can figure out how to lower their masts. A couple of yachts at anchor had their masts lowered and had mast lowering-raising systems with tabernacles and sheer legs. 

Once  we passed the bridge, we anchored in a quiet spot behind a natural sand-bar on the natural river entrance. After checking that my centerboard pivot seal was holding back the sea, the mast went up as it would on the trailer - everything can be done from the deck. Then the rest of the rigging up continued. This time the jib was raised and furled before raising anchor and motoring out. 

Motoring out of Ross River with mast raised and sails ready.  The port break wall  extends well past the bridge and provides protection from Northerly winds and waves common in summer. 

Once clear of the port's rockwall we unfurled the jib, cut the engine and began sailing. The wind was light from the North, so we were going slowly. One of the good things about sailing is you have to adapt to the wind conditions and this sometimes suggests the best way to go. So it was decided to motor-sail  upwind -destination Magnetic Island about 11 km offshore. The sea was flat calm so we got hull speed.

I checked my Garmin GPSmap60 handheld but it decided to play up with an inverted screen and no access to navigation pages. Maybe the rains in Papua New Guinea where i used it for work finally got into its micro-chip.

The midday sun up here is extreme. I knew that already, but you have to experience it to believe it, skin fry's quickly. With mainsail up there was nowhere for the boom awning to go, so just covered up with anything at hand, like a spare life jacket. Also we took shifts on the helm, the cabin with it's pop-top raised was good protection for the off-watch crew.

Pop top and fore hatch raised keeps the cabin cool. 

We  wore sun hats, long sleeves and sunblock but more could be done to ward off UV and IR radiation. Some lessons learnt for next time - like wear long pants, foot wear, better sun-hats etc. A large and very nice yacht sailing along called "It's a Beautiful Thing" sailed past with full main and Genoa heading for Cape Cleveland, she had  a broad bimini sunshade top over the cockpit and it looked very comfortable for the skipper. Hmmm, a bimini would be a nice addition..

Magnetic Island ahead!

Magnetic Islands hills loomed near and Picnic Bay's beach gradually rose into view. Rick had been in here before so knew of the reef and navigation beacon marking the safe entrance to the bay. The jib rolled away with a haul on the roller furling line and the fully battened mainsail was pulled down quietly after the halyard was released.  It was low tide and we saw some small power boats anchored at beach near the stinger net. We motored in there for a look but it looked too shallow and constricted for us, so we anchored off the end of the pier on the other side. The blue canvas boom awning was pulled from it's stowage compartment below the cockpit and was up in minutes. What a difference the shade makes.  The awning has 3 PVC pipes inside long pockets that go across it and 6 ropes tie it down to the wire lifeline that goes around the side of the boat.

Picnic Bay, Magnetic Island - the blue boom awning creates cool shade. 

While having lunch we had a look over at the wharf. It had closed to commercial Ferry traffic partially due cylone Yasi damage in Feb 2011 and partially because of a huge marina and wharf development further along the Island at Nelly Bay. People could walk out to a large safety fence about 3/4 the way out.  The wharf was great for anglers, and with little boat traffic now Picnic Bay has become a very nice quiet haven to visit.

We didn't have a dinghy aboard in order to keep things simpler on this test sail.  I vowed to get one and set foot on the Island one day.

Conditions looked OK for the first sailing off the anchor test. The awning was stowed, center-board lowered, mainsail raised and anchor pulled up. Once Ricky was back off the fore-deck, the jib was unfurled and backed to help the bow swing around and we tacked to windward to clear the reef marker post. It's a nice sensation to sail off from an anchor or mooring.

The wind quickly increased as we cleared land, it had picked up to 15 knots from the North East while we were anchored, and was on the port quarter when we raised the center-plate and set course for Ross River's entrance. Teria sailed with a bone in her teeth before 1 m seas, there was strong weather helm so i lowered the pivoting center-plate about 1 foot (30 cm). This had the immediate effect of balancing the helm significantly and the yacht tracked straighter - one more advantage of having a swing back keel, very pleased about that.

It took about 50 minutes to cross to Ross River.   we were doing about 11 kilometers/hour according to Ricky's GPS smart phone app.

Rick on the helm as we approached Ross River entrance

Ross River entrance ahead

Once again we were in the calm of Ross Rivers port breakwall, we slowed down a bit by furling the jib but the tailwind on the mainsail kept Teria sliding forwards at a respectable rate of knots. We passed the new ship basin which was home to Ross Haven Marina and the trawler fleet. They had to relocate here when the bridge began to block their access to the sea off. I don't know whether private yachts can anchor in there even for a short while so kept going

New Ross Haven Marine and Trawler harbor in Ross River

Rounded up again at the sandbar anchorage about 300 m to windward of the  grey concrete port bridge.  A fully battened mainsail is a great thing in these tight situations because it doesn't flap crazily in a strong wind like a normal mainsail would do. The fully battened main remains still when the wind is flowing on both sides of it, lowering the main can be a well paced task and not a quick grab at flapping sail cloth. Once the sails were off the mast was lowered again. It needed the two of us to do it, so though to better get a mast-crutch down aft happening so i could do the job myself next time.

We tested Teria's ability to drift downwind without a rig or a motor. It actually had some steerage way and could turn downwind then ran before the wind on hull windage alone at about 1 knot, there was also a 1-2 knot incoming tide behind us so we cover about 1 km of river silently at about walking speed with no sail or engine. Felt like something out of the engine-less era and time to see life on the river drift by. 

Finally we conceded to the modern world and increased the decibels for the final run to the pontoon. The trailer mods were not perfect as the boat was riding bow high due to the cross frames not being low enough up forward. Rick came up with a quick solution, in the boat trailer park, i lowered a bow roller 40 mm or so by unbolting it from the aft side of a beam and re-bolting it to the front side. 

The retrieval went without a hitch the repaired trailer rollers were good. Once on the hard i re-adjusted the keel rollers and side bunks. The Teria was now acceptably level on its trailer, the bow had dropped down by about 3" (75 mm) (Some serious re-fabrication to a trailer frame will be needed to drop it further.)

Once on the road home, i noticed how much the stability of the boat on trailer had increased by lowering the boat on the trailer by about 6" aft and 3" forward. This lowering also made it far easier to launch and retrieve Teria than on shakedown sail #1. The trailer is still backed in as far as possible with the mudguard tops nearly under, but now the hull can float much further up onto the trailer. This in turn allows the aft side bunks to hold the hull and stop the stern drifting off while the winch cable is being attached.

The process of mast raising and lowering in the river doesn't take much longer than doing it on land at the boat ramp. The bridge deters 99.9% of yachts so it is a very uncrowded un-rushed river and ramp with ample time and space.  Picnic Bay is a really laid back idyllic day anchorage and the Teria sailed well. All in all the 2nd shake down cruise was a success and the boat seemed about ready for regular passengers.

Ship's battery

The heart of a small yacht's electrical system is it's battery. It's need for navigation, cabin, anchor and compass lights as well as VHF radio and other electronics if fitted. I wasn't sure how many AMP hours would be needed, probably 30 or more i heard so went on the higher side to make sure it wouldn't get too discharged on a 2-3 day trip.

Charging system

The other factor influencing battery size is the type of the recharging system. Is it a shore-based  12 v battery charger or an independent at sea type such as a solar panel (or use both systems)?

For now i have a 4 amp Arlec 12 Volt battery charger bought at a car accessories shop long ago. It's fed by 240 volt AC power via a long extension lead from the house to the boat in the backyard. It tops it up in a few hours or overnight and regulates the charge level, it starts off with 2-4 amp on the dial and ends up with less than 1 amp when near full charge.

Battery charger 240 volt household AC input plug and DC output alligator clips for negative (black) and positive (red) battery terminals.

The AMP meter shows the amount of power going into battery. 

Many trailer sailers who sail allot use solar panels to keep the battery topped up. I have on hand a very old 35 W panel and recently bought the solar charging regulator and some wires etc and plan to fit this eventually.  (Jan 2016 - Finally rigged up the solar charging system!)

Battery types

It's a confusing subject for the uninitiated. There is a pleothora of batteries out there and many battery shops catering for all types of uses. To simplify the search I chose a boating shop - marine chandlers  to buy one - they have done allot of the homework and probably found the most popular batteries. In my case Bias boating was also the best location, near home.

I bought a 60 Amp hour general purpose sealed lead acid battery for around $150, (The following specs are from Bias's catalog) It's a "Sea master"  ECG expanded calcium grid battery. It's an extra  heavy duty, maintenance free, wet cell with a built in hydrometer eye. Dimensions in mm are 235 long x 172 wide and 220 high. Found out later it has a high cold cranking Amps CCA of 575 so is probably more suited to powerboats.

So in retrospect I should have got an deep cycle battery , such as an 80 amp hour "AMP Tech" for around $180 at Bias, it has similar dimensions at L269, W173 and H200mm).

A 35 amp hour AGM absorbed glass mat may have been enough, certainly allot smaller  but the cost was up per amp hour. 35AH cost around $150  at Bias, it has "significantly longer life" than lead acid batteries and it's fully sealed can be turned on any angle. A 55 AH AGM for comparison cost around $270.

Gel cells are also sealed lightweight, more costly. But you probably get longer life, smaller size etc
The lighter - smaller - longer lasting  AGM or gel cell types could also possibly be fitted in more locations like in the starboard cockpit locker or up forward in the V-berth locker.

Fitting the battery

My lead battery weighed allot and was a hefty size so wanted to keep the weight low and central with the added benefit adding a bit of extra ballast to make the boat more stable.

There is a little used space under the forward end of the cockpit behind the center board lift pipe and companionway step. A previous owner had small blocks of wood here which i removed - these were probably old battery mounts.

The Investigators production companionway step, although a nice piece of workmanship, was permanently riveted onto the bunks each side and made it impossible to access the relatively voluminous space behind the step. Besides wasting valuable space on a very small boat was a sad state of affairs for maintenance too, so drilled out the rivets, cut a bit away at the pipe and removed the production step from the boat.

I cut a battery base from 12 mm plywood. Wood gives a bit of spring and shock absorption. Made up a battery bracket with 30 mm angle steel and 10 mm threaded rods. Two holes were marked then drilled through the ply battery base. The angle iron was fabricated to form the top plate with two holes for the threaded rod drilled.

 The base was positioned in the boat and the holes continued through the fiberglass floor. I took care to make sure i didn't drill through the hull, it gets pretty close but there was about 10 mm spare each side out to the keel sides. It was a bit of a Chinese puzzle and contortionist game to get the bolts in and standing up but it all bolted together nicely and should keep the battery firmly in-place during road trips, rough weather, knock-downs or worse. It should actually help right the boat when it heels over.

The battery has some room each side of it still. One side  is room for the 8 foot long rolled up boom shade awning. It can be slid past the battery. The other side has room for two 8 foot long oars and the boat-hook to be stowed.

Battery under cockpit. Long items stowage is on either side of battery. Awning is to left and oars, and mainsail-boom etc can go to right. Negative power cable is off terminal to isolate battery. Battery hold-down is very robust. 

As long as a battery is about 173 mm wide it could be much larger in the other two dimensions (depth and height). The extra weight in this location would be OK. This may be of use if an electric auxiliary outboard is ever experimented with.

A quickly removable step was needed but I ran out of time to modify the production step for this function. Quickest solution was to make up a temporary wooden step from 25 mm hardwood which sat on the bunk tops. A notch for the centerboard pipe was cut in the wood step and the bunk fiddles wedge the front end in place. It's a  heavy and very strong step.

Removable wooden step

With the step out, it is now possible to access and do maintenance work below the cockpit. Checking the battery, Cleaning the bilge - I think it was the first time  that anyone had ever cleaned the bilge under the cockpit. Quite allot of rubbish from corroded coins,to bits of wire, rusty screws and other accumulated crud were removed.

Battery, bilge sump, lift pipe and stowage access by removing step.

Battery lead removal  to isolate it is easy. 

The location is hopefully a fairly dry one, it is tucked under the cockpits edge and behind the companionway hatch opening.

Floorboards in the cockpit locker

Next job, the port side cockpit lockers floorboards were replaced.

I read that early Investigator 563's had an outboard well in the port cockpit locker. At first i didn't recognize the remnants of this on Teria as it was covered by thin plywood floorboards. The discovery was made when i had stepped on the aft floor, which was rotten by now and I crashed through it. Being an eternal optimist i left the forward floor board in only to meet the same fate later.. This left no choice but to replace them with something stronger.

Remnants of an old locker floor board

So the old 6-8 mm thick ones were recycled as garden mulch.

Early investigators had an outboard well in the locker, it looked like this was the case in Teria at one time.    It may have been  noisy, smelly, maybe a bit dangerous to have a sparking outboard next to 5 gallons of petrol in a confined space, also valuable storage  and some hull buoyancy was lost. I also suspect that when a boat heeled to port the well compartment could have flooded.  Nearly all Investigators adopted transom mounted outboards after locker wells fell out of favor.

Signs of an outboard well remain in the port locker. I inadvertently demolished the aft floorboard covering the remnant outboard well, 

Nothing in the lockers well was square. So made up  templates of the floorboards with thick cardboard from packing boxes.. These were easy to cut and shape with a Stanley knife until they fit well.

Cardboard floor template in place.

Then the templates were taken out and the edges were penciled in on the 12 mm plywood. The floorboards cut out with circular saw. Only a little bit of pruning of the edges with the saw and surform plane was needed to get the final fit.  The  floorboards allowed the petrol tank and other gear to sit flat safely once again. Also they are strong enough  to walk on.

Lots of Bad weather lately it's Feb 2014. So time to remove the floorboards and clean out the locker.
Used a Karacher high pressure water jet machine to blast away grime, it took away the remains of some  flaking silver heat shielding glued to the bottom of the hatch too.

Karacher high pressure water jet gun. garden hose attaches to pump body and the motor is 240 volt electric.

Next engine degreaser was scrubbed around, an oily layer had got on every surface, even high under the cockpit coaming. This and the reflective under hatch heat shield layer, suggests that it once was an engine room with an outboard well which was later patched over. The square ply box glassed to the hull may have been a 12 volt battery box in the old days. More water jet blasting also removed loose white epoxy paint applied after construction.

Degreasing the starboard locker.

There is a black rectangular hole which gives access to the hull. The old speed log paddle wheel fitting still sits in here.

The old outboard well possibly glassed over.  It looks like an old battery box on top right.

 The ply floorboards were dried, then belt sanded before 3 coats of "Ultradeck" wood stain finish was brushed on to seal it.

sanded and ready to coat

Drying deck oil coat

The floorboards have a natural non-skid surface with the wood stain finish. Sometimes you need to stand on them to get stuff out.

Floorboards back in place

I tried stowing the 2nd anchor in the old well but decided against it after a few trips. Water does fill the sump a bit as the hatch seals aren't perfect, then its hard to bail out. Stow the 2nd anchor high and dry in a small crate in the other locker now.  

 Split floorboard allows access to sump below while the 24 liter (5 gal) petrol tank's in place.

Locker hatch closed

Trailer overhaul

The old trailer was pulled out to do the centerboard work , so what better time to concurrently overhaul the trailer.

The photo below show the trailer as it was when i got it. The Rear rollers assembly was a rusty conglomeration. It looks ok thanks to cold gal, great stuff for getting road safety certs, But behind the pretty face two guide rollers had seized, the lower one rolled but the whole thing had been welded on a bit too high. The side bunk supports (wooden with white carpet) which hold the bilges up and stop the boat from toppling over sideways, were welded in a fixed position. Besides looking a bit flimsy they were not adjustable and took far too much weight - a possible reason why the boat didn't want to slide off the trailer at the ramp. Another reason was the second rear roller had a bent pin and would rotate only a half turn before seizing.

Next i bought trailer parts - New rear rollers etc. Found out that in Australia blue color ones are for aluminium hulls and are too hard for fibre-glass hulls. So bought red rollers with the medium flexibility rubber -plastic? compound designed for fibre-glass. The trailer had allot of black rollers, these are the softest type but more prone to damage themselves, may be good for wooden boats??

I had only overhauled one other trailer before the Fatty knees 8's box trailer which is a lightweight rig Boat about 50 kg - trailer about 100 kg . The Investigators had to hold up and move a bit more weight about 900 kg of boat and 300? kg of trailer. The Research of  trailers on-line and on the streets revealed lots of good information, the investigator forum again had some good threads and pics to get a better idea. Pics of Investigators on their trailers gave a good impression of where the boat should sit to achieve safe balance etc. I wanted to lower the whole boat by about 4-5" on my trailer - This would make it easier to float off and more stable on the road.

The trailer before work began

At the wyloyard the trailer was pulled out clear of the hull into a nice shady spot. I had planted a sapling deciduous tree long ago and it now grows a very thick crown of leaves in all directions to shade from the western sun most of the hotter months of the year. The shed roof provides good morning shade.

Shade makes all the difference to work outdoors in the tropics

The 5" and 9" angle grinders cutting discs removed the rear roller amalgam but soon discovered the rear box section beam had partially rusted out at its lowest point. So i fabricated a 3 mm plate patch and welded it over the  area.

The trailer was raised onto it's sides for easier work. I chained my 1/2 ton chain-block to the roof beam-support pole join. It's nice to have a strong shed frame capable of lifting heavy objects with chain-blocks, sort of like having your own slow-moving crane around.

The welding is easier down hand and also could access underneath the trailer frame to spots usually missed.

Rust treatment was grinding - chipping the thick stuff off, wire brushing , phosphoric acid to convert rust into black phosphate compound bonded to clean steel, cold galvanizing metal primer spray and then grey water soluble metal primer.

The new rear rollers C-mounts were welded on. Then the keel rollers checked, oiled up to regain adjustment and repaired as needed.

The trailer had way too much down pressure on the tow-ball so i moved the axle 5" forward. Cut away welds attaching the mudguards to the upper frame but left them on the lower axle frame. This allowed it to move once the 6 big u-bolts were released.

Adjustable height side support bunks were needed next. First the wooden bunks were unbolted - most bolts had rusted up. angle grinders cut the fixed supports off the trailer.

Building side bunk adjusters. Bought some 30 x 30 mm galvanized box section tube with 2 mm walls. Recycled the 20 x 20 mm square solid rods fittings which held up the side bunks, de-rusted and painted these - they would later  insert into the adjuster pipes.

To make the adjuster box pipes i cut them to length, the drill press was handy to drill out holes for the locking bolts.

With the 1/2" holes drilled the locking bolts nuts were welded to the box pipe.

Having good welding gear helps allot. Awhile back i bought an automatic shading welding helmet as their price has dropped to affordable levels over the years. These are great as there is no dark glass flap closing by hand when arcing up. They have a small solar panel to power them up from weld rod light too. Another must for me is to use my reading glasses, my usual bifocals just aren't the right tool for this job.  The job quality gets a whole lot better! Good Protective clothing is needed, weld gloves, long sleeves, long pants and slip on steel cap boots. It's hot in summer here, around 30-35 C so have 4 industrial fans  to stay cooler. The most powerful one sits on the ground, has a circular shroud, makes a huge noise and blows like a wind tunnel. It has to be at least 3 m away and not directly aimed at the welding area or it blows the arc gasses about and spoils the weld.

The bunk adjusters were painted , assembled and welded onto the trailer frame. The recycled brace rod was then welded on too. 4 side bunk adjusters were fitted.

Side bunk adjuster - two lock bolts grip the sliding square rod inside. The brace rod adds allot of strength. Axle U-bolt is also shown.

The aft guide rollers  were a 1970's product but looked just right for the job of capturing the keel and guiding it along the center of the trailer. I checked with the marine chanderies in town but nothing like this was available, the choice is wobble rollers only. So restored the originals. First the rusted in axle pins were removed and reconditioned. My slide adjusters were similar to the side bunks except thick wall galvanized round pipe was used. They were welded on to the aft beam.

Trailer rollers reconditioned. The blue side rollers were later found to be too high, so they were lowered to the level of the red keel roller..

Centerboard restoration and refit

The restoration began with knocking out the old plastic pivot bushing at the workbench, keeping it and other pivot bolt parts together so measurements could be taken to replace the entire pivot unit assembly.

The rust was removed, mostly with a power wire brush on a 5" grinder and 9" angle grinder with cutting wheel.

One thing that surprised me was the completely square edges on the 12mm thick centerplate. These looked very un-hydrodynamic so i set to it with the 9" grinder to reshape the forward and trailing edges into semblances of a parabolic foil shape to improve sailing performance.

There, that's starting to look better! A final bit of rust converter acid  to neutralise the deeper pits. The hot dip galvanising plant recommended some paint stripper to make sure no remnant paint remained anywhere as cold gal won't stick to paint etc.

A pic of what the center-case slot looks like without the plate, its a hardly-ever seen (let alone maintained) part of a trailer yacht, its either under water or on the trailer near the ground with rollers and steel beams all around it which prevent easy access to it.

The center plate of the 18 foot Teria is a similar size to the daggerboard of the 8 foot long Fatty knees dinghy. The Teria has a shoal draft fixed keel that makes up about 75% of the yachts lateral resistance, the center-plate is about 25% of the lateral resistance. The Fatty knees has only a 1" deep rub-keel and small skeg so it's dagger board does most of the work.

The pivot assembly was re-built from scratch. A stainless 10mm diameter bolt and the remains of the 3 bushes were taken around town to see what could be done. I started at the marine chanders, went to a power boat chandlers and they knew of an engineering firm just down the street - Arndt Engineering.. In luck, they had refitted yacht rudder shaft assemblies. The callipers were taken out, centerplate and pivot bolt bits were left with them, they made the bushes on a lathe with white polyacetate? a tough hard wearing plastic suitable for marine immersion for a very reasonable fee. They drilled out the pivot hole a bit and allowed for some clearance after the cold gal was on. The center bush was slightly larger than the original which made it thicker walled and stronger.

The center plate went to the galvanizing plant, it weighed around 20 kg which was just under the 25 kg minimum lot weight. So paid $55 for the plate's acid bath and hot dip in the molten zinc vat. The going rate for hot dip galvanizing at the Bohle plant is $2 / kg. Due to a long work Que it took a week to get done but it was worth the wait, it sure did look like new.

Back at the boat yard cheek pads were fabricated and fitted. I bought 2 mm black polyethylene? plastic sheet (aka chopping board plastic - is a bit slippery) at Northern Plastics. Cut round circles 270 mm in diameter with a 20mm hole in the middle.

The plate was refitted with the help of a friend. Mike got the pivot bolt in while i lifted the plate up. Some pencil marking and a strong torch helped align it. Afterwards it was apparent that the 4 mm packing was not enough the plate was too loose in the case and wobbled about. So i dropped it out and added a third 2 mm spacer.

This time i got it in solo and allot easier. The plates 20 kg weight was held up by the trolley jack below, when up in the case there's almost no fore and aft play so the pin aligned with the hole far more easily. This time, with  6 mm of plastic packing, the board fit snugly with no sideways movement.

The benefits of a "deco" floor, dug a small trench for centerplate to lower into.

Note: Decomposed granite "Deco" is an economical material often used for car driveways up here. It can be spread out like soil, but after being compacted (by cars wheels) sets hard. However it still remains workable, it can be added to or even dug through (eg to lay a pipe). It's great on the expanding clay soils we have, as it never cracks up like concrete. In the open, grass will grow over it. Under a roof it's resistant to grass and weeds, i just spray the few that do sprout.

The pivot bolt assembly got bedded down with liberal amounts of silicone sealant to prevent leaking.

Pivot bolt nut and washers inside the bilge area. The high compression plastic washers spreads load out while having a little "give" 

To refit the lift wire i bought a 3.2 mm swaging tool. It looks like a pair of bolt cutters but with a different business end that crimps the swage tight around the wire.
This time the eye was not integral with the plates lug, it was attached with a screw pin shackle instead, so future maintenance (possibly by some new owner?) will hopefully not require the purchase of an expensive swaging tool!

Lift wire now shackled to center-plate for easy plate removal.

Everything together - the plate worked well. Rising up into it's case with a haul on the lift rope in the cockpit. Lowering down by letting it out. I marked the lift rope with 2 positions, 1/2 raised and 3/4 raised. The system is simple, no purchase block and tackles required, just a pipe for the lift rope-wire, exit sheave and horn cleat.