Improve Your Catalina 30: Upgrading the World’s Most Popular 30-Footer


The Catalina 30 is a remarkable success story. We suspect that more Catalina 30s have been built than any other boat of that size anywhere in the world. While the basic boat has remained unchanged since it was introduced in 1975, there have been dozens, perhaps even hundreds, of minor developments in the boat in the course of a produc­tion run that is approaching 4,000 hulls.

catalina 30 sketch

The advantage of a boat in production for so long is a high degree of product refinement over the years. The challenge for the owner of an early version of the boat is to upgrade his boat to the standards of models currently in production.

In the case of the Catalina 30, a number of bulletins have been published by the builder over the years, detail­ing improvements to the boat. In addition, there is an ac­tive owners’ association, and many individual owners have embarked on significant programs of upgrading their boats.

As a rule, the changes to the boat over the years of pro­duction have been true improvements. At least one change, however, was less successful. The original changeover to diesel power resulted in a boat that was significantly underpowered, according to many owners.

Almost all the suggestions presented here for the upgrading of the Catalina 30 come from owners. Over 80 responded to the detailed questionnaire about the boat, and many added more pages of comments to the responses. The owners responding own boats that run the gamut of the production history of the Catalina 30, from hull number 2 to hull numbers well over 3,000!

Here, then are the suggestions of Catalina 30 owners for the improvement of the world’s most popular 30-footer. Not all will be applicable to any particular hull. Many of the changes suggested or performed by owners of early boats were incorporated into the production of later boats. In addition, some of the changes became factory retrofits, so that some older boats have been upgraded to the specifications of newer models.

Hull and Construction Details

Until very recently, all through hulls in the boat below the waterline consisted of gate valves screwed onto pipes fiberglassed into the hull. Current models utilize RC syn­thetic seacocks incorporating recessed through hull fit­tings.

The advantage of the old system is that there is no ex­posed, drag-inducing external skin fitting. The disadvan­tage is that gate valves are a generally poor substitute for seacocks, since it is not always possible to determine if they are open or closed, they can be jammed in the open position by debris, and they are as a rule more subject to corrosion.

Replacement of the gate valves with proper seacocks, either of tapered plug or ball valve construction, is recom­mended. Proper skin fittings should be installed at the same time, and these can either be faired in externally, or recessed (see Better Boat, February 1984).

As a rule, deck hardware is installed with large washers, but without proper backup plates. Stanchions, pulpits, and cleats can be made stronger by the addition of aluminum backup plates to help distribute load.

Like many other builders, Catalina has finally abandon­ed running lights mounted in the topsides. If being seen at night is a priority, install a pulpit-mounted combination running light, as is used in current production models of the Catalina 30.

Generally a little more attention to bottom detailing on the Catalina 30 should get you
a little more speed. The rather large gap between the skeg and rudder should be filled in with fairing flaps to reduce crossflow. This im­provement, suited to many boats, will be detailed in a future issue. In addition, lines and seaweed can jam bet­ween the forward part of the rudder blade and the bottom of the skeg. A deflecting rod, perhaps a piece of 5 11 6″ diameter bronze rod, can be glassed into the bottom of the skeg, just overlapping the opening between the rudder blade and the bottom of the skeg. In New England, this type of rudder/skeg configuration, without the deflector, is known as a potcatcher because of the amount of lobster pot warp that can lodge in the opening.

Prop skeg configuration has changed slightly over the years, but as a rule, the skegs are fairly clean airfoil bronze castings. On the new Catalina 30s we examined, the casting was quite rough, however, and would benefit from a touchup coat of epoxy and microballoons, followed by a thorough sanding to smooth it out.

Prop wash when under power can make the Catalina 30 a bear to handle for extended periods. The original rudder was redesigned, and many older boats have been retrofitted with the improved rudder which greatly reduced the helm problem. If you bought your Catalina 30 used, and find the helm excessively heavy when powering, contact Catalina for information on the new rudder. If in doubt, send a photograph of your rudder to the company. Theyll tell you whether you have the new or old version.

Rig The rig of the Catalina 30 is decidely old fashioned, with its untapered mast tube, wooden spreaders, and unanodized mast and boom. Mast and boom should be painted, both to reduce surface oxidation and improve appearance.

Standing rigging, chainplates, and rigging fittings bring negative comments from a surprising number of owners, who consider this part of the boat a weak point. Beef-up kits for lower shrouds are available from the builder at nominal cost, and most older boats have had this modification If you have an older boat and don’t know, compare your boat to a recent model nearby or take a picture and send it to the builder.

If you have closed body, stainless steel turnbuckles, replace them with open body turnbuckles of bronze, chromed bronze, or mixed bronze/stainless steel construction. Steel on steel turnbuckles have a nasty habit of seizing, and the closed body makes its difficult to judge the amount of adjustment left in the screw.

The small diameter wire used for shrouds and stays stretches excessively, according to some owners, making it difficult to maintain headstay tension. Going up one wire diameter, at least on forestay and backstay, is suggested by many owners.

catalina 30 propellor

Although it is rarely mentioned by owners, we would suggest replacing the wooden spreaders with airfoil aluminum spreaders.

Internal halyards, led aft along the cabin top to the cockpit, are a popular modification. There is just enough room between the forward edge of the seahood and the cabintop handrail to put turning blocks on the deck for the halyards. Be sure to stagger the halyard exit holes on the mast, and fit them with chafe guards to keep the halyard wires from eating into the mast tube.

The boat quickly develops weather helm as it heels, a not uncommon trait of wide boats such as the Catalina 30. Even sailing upright on a broad reach, there is a fair amount of weather helm. This is minimized with the tall rig/bowsprit option, and can be reduced on the standard rig by raking the mast forward slightly, and having the mainsail cut with minimum roach. Unfortunately, reducing the roach gives away sail area that the boat may need in light air. We see no reason why the bowsprit couldnt be added to the standard rig boat to move the center of effort of the sail plan further forward. This will, of course, increase the boats rating under any racing rule.

Although the shrouds are set well inboard, the genoa track is mounted atop the toerail. This may be fine for reaching, but it leaves too wide a sheeting angle for going upwind, according to owners. Installing a genoa track inboard, between the stanchions and the cabin trunk, would decrease the sheeting angle by about 5 , and significantly improve windward performance. It may be necessary to install foot blocks at the aft end of the existing genoa track to get a good lead to the sheet winches, but this inboard track could probably be used with the working jib as well, which has a poor lead to the jibsheet winches without leading the sheet through a second block on the outboard track.

Traveler location is problematic. At the aft end of the cockpit, the lead to the boom is poor, and the mainsheet can pose a problem when jibing, according to owners. Locating the traveler forward, over the companionway, both interferes with the companionway and complicates the installation of a dodger.

As on most boats, we suggest the installation of the largest self-tailing jibsheet winches that will fit atop the coamings. Overkill is a nonexistent word when it comes to handling headsail sheets, and the self-tailer is the only way to go. Once youve tried them, youll never go back.

Engine and Installation Over the years, five different engines have been used in the Catalina 30: the workhorse Atomic Four gasoline engine, and the Universal 5411, Yanmar YSB12, Universal Model 18, and Universal Model 25 diesels. The engine compartment was designed for the Atomic Four. Some of the diesels present a tight fit.

According to owners, boats equipped with the Yanmar YSB12. and Universal 5411 diesels are underpowered. The current Universal Model 18 is only slightly larger. The two most desirable engines are the Universal Model 25 and the Atomic Four.

The Atomic Four is relatively quiet and powerful. All of the diesels are more noisy, and with the exception of the Model 25, much less powerful. If youre going to repower, go to the Universal Model 25. Slight modification of the hatch under the port settee will be required to fit the diesel, which is about 3 taller than the Atomic Bomb, as it is affectionately known.

If you can possibly manage it -and space is at a premium here -try to fit some sound insulation in the engine compartment, as the boat is noisy below underway with any of the diesels.

Since the prop installation is exposed, the boat could benefit from a folding or feathering prop. Since we have experienced a slight loss in speed and power with most folding proprs, don’t do it unless you have one of the larger engines. As a rule, we prefer the feathering Max-prop to a folding prop because it generates equal thrust in both reverse and forward, unlike most folding props. Watch the tip clearance carefully, as there isn’t much room here.

If you have a 25 amp alternator and dual batteries, you should switch to a larger, 55 amp alternator. According to owners, this is a simple adaptation.

While dual batteries have always been optional, most boats are equipped with them. If yours isn’t, do it. If the batteries are in the original port side location, shift them to the starboard side, under the chart table. This will eliminate the slight port list found in some older boats.

Comfort and Convenience

Ventilation is a problem on older boats. According to many owners, the sliding port in the head leaks, and there is no provision for ventilation in bad weather. The forward-sloping bulkhead between the cockpit and the main cabin makes it impossible to leave a hatch board out in rain or heavy weather.

Opening cabintop ventilation hatches over the head and forward end of the main cabin, as found on new versions of the boat, can be easily installed on older boats.

catalina 30 icebox

A cockpit dodger makes it possible to leave the hatch open in bad weather but makes access to the mainsheet a problem if the hatch-mounted traveler is installed. If you don’t want a dodger, and havent led the halyards aft along the cabin trunk, cowl vents in Dorade boxes on either side of the cabintop at its aft end will provide ventilation with the main hatch shut off.

The strong taper of the sides of the companionway, coupled with the fairly narrow internal and external teak pieces which hold the drop boards, strikes us as a serious weak point. While modification of the hatch, which we feel is just too big for offshore use, may not be practical, theres no reason that the teak retainers for the drop boards can’t be made an inch wider, both inside and outside. This would mean youd have to lift the boards further to either remove them or install them, but it would also make them more secure in a knockdown.

Modifications belowdecks are as many and varied as the personalities of the owners. As a rule, most Catalina 30s from all years suffer from inadequate division of storage spaces. Vertical dividers in the galley storage spaces behind the stove would greatly increase the practicality of that storage area.

Several other galley improvements will pay dividends. While the two galley sinks help give the Catalina 30 the feel of a big boat, the outboard sink, according to owners, can flood back through the drain if the boat is well heeled on starboard tack. Wed eliminate the outboard sink, fitting a dry well for storage instead. The inboard sink probably can’t flood under most sailing conditions, so the sink drain can then be left open for use.

Owners report mediocre icebox insulation, particularly on older models. Some owners merely stuff fiberglass house insulation between the outside of the icebox and the hull, but a far more effective solution is to glue on sheet urethane.

Older boats have no insulation in the icebox lid. This can be corrected by gluing sheet urethane to the underside of the hatch, fitting as closely to the sides of the hatch as possible to still give clearance on the inside. The sheet urethane can be glassed over directly. Dont use Styrofoam -its less efficient -and don’t glass over it, if you do. It will dissolve in polyester resin. Even the insulated hatches on new versions of the boat need improved gasketing between lid and icebox to reduce heat intrusion.

The chart table has been improved on new models by making it flat, rather than angled. Angled chart tables only work when they are mounted athwartships, rather than fore and aft. Theres no reason older tables can’t be modified in the same way. While youre at it, add drop leaves to the fore and aft ends of the table to increase the working surface, and make the fiddles removable so you can use all the surface.

If the boat is to be used for any serious cruising, consider replacing the standard alcohol stove with a gas stove. CNG is offered as an option on new boats, and it will greatly increase the livability of older boats. We guarantee that the improved performance of the cook will make this a worthwhile change every time.

Your cruising will be more comfortable if you add an extra water tank under the forward cabin berth. This has become a standard option on new boats, and is an easy retrofit in older boats. Do not, however, keep this tank full for daysailing or day racing, as the weight this far forward will accentuate pitching moment.


The Catalina 30 comes as a fairly well equipped basic boat. However, the responses of owners indicate that a lot of customizing can significantly improve the boats function.

Because there are so many Catalina 30s in the world, it has probably been the subject of more minor modification than any other 30-footer. The changes suggested here are by no means all the modifications that owners have made. Rather, they are either the most common ones, or the ones we feel do the most to make the boat easy to sail and easy to live with.

Every boat is a compromise, from the moment it leaves the designers drawing board until the end of its life. With a lot of thought, some money, and a fair amount of thoroughly enjoyable labor, you can improve any boat. And the Catalina 30 must surely be one of the most thoroughly owner-improved boats in the history of boat-building.

Practical Sailor has been independently testing and reporting on sailboats and sailing gear for more than 45 years. Supported entirely by subscribers, Practical Sailor accepts no advertising. Its independent tests are carried out by experienced sailors and marine industry professionals dedicated to providing objective evaluation and reporting about boats, gear, and the skills required to cross oceans. Practical Sailor is edited by Darrell Nicholson, a long-time liveaboard sailor and trans-Pacific cruiser who has been director of Belvoir Media Group's marine division since 2005. He holds a U.S. Coast Guard 100-ton Master license, has logged tens of thousands of miles in three oceans, and has skippered everything from pilot boats to day charter cats. His weekly blog Inside Practical Sailor offers an inside look at current research and gear tests at Practical Sailor, while his award-winning column,"Rhumb Lines," tracks boating trends and reflects upon the sailing life. He sails a Sparkman & Stephens-designed Yankee 30 out of St. Petersburg, Florida.


  1. You guys use a spell checker? I can see a dictionary not having some of the nautical terms, but you forgot the apostrophe on LOTS of words like theyll isnt LOL

  2. Very interesting info. I have a 1979 tall rig 30 ft catalina and looking for the Tensions on the rigging, especially the Lower afts. If anyone can suggest where this is listed, It would be appreciated


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