Halyard tension and friction
I hope my input is not too wordy... but your boat has enough displacement and sail area where you are well into the gray area of whether or not to "need" a winch to get halyard tension correct.
I have crewed on an E- 27 with the halyard led aft to a single-speed housetop winch (just like larger boats) and it worked fine. I note that this "fix" does add complexity and more friction.
I used to sail a similar size boat with a fractional rig and a larger main -- we considered the winches vital.
OTOH, as you have noticed, adding a winch to the mast will help your problem and involve the least other changes... but only after solving the winch-mounting quandary.
I have seen welded aluminum flat mounting pads, and contoured teak or plastic pads used to mate the flat winch base to a curved mast side. All had problems with the SS fastenings intereacting with the aluminum alloy mast over the years. Some yacht builders would put a turning block at the mast base and then locate the winch on the house top a foot or so away (C‡C and Tartan, to name two).
If you read the fine rigging book by Brion Toss, one of his big lessons is to always look at rigging problems in terms of the whole load path and not just get distracted by one part of it.
In hoisting your main, start with the place where you shackle on to the headboard just above the boom and... follow the path.
First, the slugs have to ride up the extrusion with no binding or undue friction. Second, the halyard does a high-friction 180 degree turn over one (or two) sheaves at the masthead. With a cleat at the base of the mast the friction load stops there...
Note that some of our common "solutions" add more friction -- like a turning block at the base, and a cheek block to route it aft, and then a winch by the hatch. Note that winches, whether on the spar or aft, also have their own built-in frictional losses. We used a can of MacLube on slugs once or twice a season, and on all sheave axles -- it helps a lot.
Let's be sure we first understand what you have now -- external halyard? all line or is it wire halyard with a rope tail?
Then, can you (or some light weight friend) be hauled up there to lube up the axle of the masthead sheave(s)?
In short, do not be too quick to drill holes in the mast wall.
There are a lot of experienced E-27 sailors on this site, and they will help you as best they can. Lastly, if you have a digi camera, you can post small pics of your cleat, sail slugs and whatever else seems pertinent which will help fellow Ericson owners all over the country assist in the diagnosis.
:nerd:
Welcome to the group!
Loren in Portland, OR