← The model library
Model profile · for Great Loop buyers
Mainship 400 Trawler
What the published record establishes about this model, what owners report,
and the questions worth asking while a boat is still a listing. This page is about the
MODEL — a specific hull always gets its own homework.
The published record
| Length overall | 41.33 ft |
| Beam | 14.17 ft |
| Draft | 3'8" |
| Fuel | 300 gal |
| Water | 130 gal |
Source: boats.com sea-trial spec box.
A listing that disagrees with these numbers isn't necessarily wrong — but the
disagreement is a question to resolve before it costs you.
Clears the water gate with ease at 3'8" — air draft has no published basis at all, so this hull's own tape measure decides. Drivetrain choice and tank inspection are the rest of the homework.
Mainship's third-generation trawler (introduced 2003), purpose-built for exactly this kind of cruising, and orphaned with the rest of Mainship since 2012. The buy questions: what this hull carries aloft and how tall it really is, which drivetrain and what that choice traded, and the aluminum tanks' condition. Model fit and model risk only; condition is for a surveyor.
How to read this: 🟢 Fact = confirmed against a document, spec sheet,
or owner. Everything else — Claim, Pattern, Question, Context — is not yet
verified: things to check, not settled truth. Sources are linked where published.
The published numbers
FACT
41'4" LOA, 14'2" beam, 3'8" draft, 24,000 lb — 300 gal fuel, 130 water.
The boats.com sea-trial spec box. The '400' name undersells the length: slips and haul-outs price the 41'4".
src:
boats.com sea trial (Tom Thompson)
Air draft
CONTEXT
No professional review publishes a bridge clearance for this model.
Neither the boats.com sea trial nor Yachting's review states one, and listing figures scatter (12'8" to 16'4" mast-down have both appeared). A folding radar mast was a factory OPTION, so hulls genuinely differ. Height figures are stated often and confirmed rarely; on this model there isn't even a stated factory number to argue about.
src:
boats.com options list (folding radar mast)
Your move: Establish what this hull carries aloft, whether the mast folds, and tape-measure everything-up before planning any fixed-bridge leg.
Tanks and systems
FACT
Two aluminum fuel tanks, mounted outboard.
Aluminum tanks have no fixed expiry — inspect, don't assume. Outboard placement decides what inspection access looks like on this hull.
src:
Yachting magazine review
Your move: Sight the tank bottoms and their outboard mounting areas at survey.
CONTEXT
The generator lives aft under the cockpit in its own compartment.
Good for noise at anchor; check it where it actually is — the afterdeck hatch, not the engine room.
src:
boats.com sea trial + Yachting review
Livability
CONTEXT
Two staterooms, one head — and a reportedly spacious engine room even with the largest single.
boats.com found easy all-around access to every service point on the 385-hp single. Don't import other Mainships' engine-room reputations in either direction; open the hatch on this hull.
src:
boats.com sea trial
Buying
CONTEXT
Mainship has been an orphan brand since 2012.
The Luhrs Marine Group (Mainship, Silverton, Luhrs) filed for bankruptcy in 2012, having ceased powerboat production that January. The hulls didn't change; the parts-and-support questions are the standard orphan homework, and the owner community is large.
src:
Trade Only Today, 2012
QUESTION
The predecessor 390 has documented quirks — ask whether this generation shares them, don't assume either way.
The 390's record (public Trawler Forum testimony, held in its own profile) includes sealed-foam swim-platform flooding on original platforms and a wallowing gait in a following sea. The 400 is the third-generation redesign, not the same boat. The honest move is to put both to the seller and the sea trial: how does she run in a following sea, and what's the swim platform's construction and drainage story?
src:
Mainship 390 profile's Trawler Forum citations (predecessor scope)
CONTEXT
The record is quiet — and that's a finding, stated with its limits.
In the professional reviews we've opened (the boats.com sea trial, Yachting's review) and the owner discussion gathered since, no recurring mechanical defect pattern has surfaced for the 400 the way one has for some contemporaries. That is an absence in what we've searched, not a guarantee about any hull — individual boats fail surveys for individual reasons. The model's loudest open items are the unpublished air draft and the predecessor 390's separate record.
src:
scope: the sources this profile cites, searched through 2026-09
Engines
The engines research — factory options, tested performance,
and the engine-specific questions our members' dossiers carry — is part of the
full profile inside the product. It travels with every dossier and survey brief
built on this model.
Looking at a specific 400 Trawler?
This page is the model's story. The product reads an actual listing against it —
your requirements, the hard gates, the record cross-checks, and the questions ready
to send. See a full
sample dossier first if you like.
Join at the founding rate →