Our hatch used to wake up the dead when opened or closed!
I've read of several solutions but they all involved a fair effort. My thought was to simply sleeve the exposed fiberglass edges of the hatch front - and ensure the rear slid on wood.
I started with 1/4 inch hard polyethylene tubing. It's available at most hardware stores and used for furnace humidifiers, water softeners etc.
Cut a length to fit the forward hatch edge, split it down the middle with a knife, open up the slit and slide it over the fiberglass edge. You may want to use a bit of silicone seal to keep the tube in place, but the weight of the hatch is more than adequate. Ours has never fallen off.
As for the back of the hatch, it will only screech if the wood has worn to the fiberglass. Just trim away the fiberglass so the hatch is sliding on wood. The wood won't wear further if you coat it with Cetol or smear some epoxy on it.
The hatch is virtually silent now! I keep a few extra lengths of pre-cut tubing on board, in case I loose a slider or they wear out.
Smelly fuel locker
Our M20 has the fuel tank located in the port lazerette. This area is open to the interior and we often have the smell of gas inside. We liked where the fuel tank was located - gives more cockpit space as well as one more "non-sailing" item hidden from view. The following pictures show the tank location as well as the two openings to the interior.
I remember someone commenting on the fact that the lazerette bottom slopes. This actually works well with our fuel tank. It has a flexible "clunk" style pickup - and scavenges every drop of fuel due to the slope.
I was simply going to fiberglass over the openings with West System. Unfortunately, the rear opening is to the transom. This area flexes substantially when the outboard is in use. Fiberglass would break the first time we used the motor - had to think of something else...
I finally decided on 1 1/2 inch closed cell polyurethane foam. This material is very flexible, air tight and glues well with silicone. After much trial and error, I ended up with pieces that were a tight fit in the openings. I used 3M 5200 to glue them in place followed by a bead of 5200 to ensure everything was airtight.
Noisy wires in mast
When I initially installed the masthead VHF antenna, I ran the coax down the inside of the mast. Bad idea! It goes "tink, tink, tink" all night long as the boat rocks!
I remember reading about someone using foam plastic pipe insulation - so I headed down to the local builders store and purchased 8 lengths of 1/2 inch. The material I purchased is slotted with adhesive to glue it together. I shoved the wires through each piece and stuffed them up the mast! (hint: run a band of electrical tape around the top of the first piece of insulation - keeps the seam from separating). All was well until they reached the spreaders, which have a stainless through bolt blocking the way. Had to remove the bolt, but no big deal. The mast is totally silent now.
I've always wanted a wood floor. Besides taking the strain off an area with known "core" problems, it looks much nicer than fiberglass.
It took some time to decide on material. Teak was far too expensive and pressure treated was out of the question! I finally settled on western red cedar. Seven 1 X 4's ended up being EXACTLY a perfect fit. Six cross pieces seemed about right. The outer ones use stainless steel screws (for decking - 1/16 the cost of the same item at the local marine store). This allowed me to tack it together, trial fit, adjust etc until it fit perfectly. Screws in cedar don't hold very well, so the other cross pieces use exterior construction glue. The bond is far stronger than anything I could accomplish with screws - and holds up well in water.
Finally, a couple coats of Cetol and it was a close match to the existing teak. The result is also extremely strong - no flex in the floor anymore.
The best improvement you can make to a stock Ooyang Matilda 20. Under normal sailing, the metal rudder blade deflects rearward - substantially increasing tiller pressure and greatly reducing rudder authority.
This is often mistaken for excessive "weather helm" - and can add enough tiller pressure when close hauled that both hands can barely hold it.
I tried several methods and the one I like best can be seen in picture. The cleat is a low profile, metal "racing clamcleat" by Harken. The small block is arranged so the line only needs to be pulled about 4 inches to lock the blade down. It also lets the blade stretch the line and deflect back if you ground the rudder. Seems to work well.