Determine Model from Hull ID, Stencil, or State Title Numbers

[Trmason1]

(Inferred questions]
Q1: how can I determine the model type of a 13-foot hull from its Hull ID Number or Stencil Number or a number on its state-Issued title?

Q2: how can I determine the model type of a 13-foot hull from other characteristics besides the numbers mentioned above?

Fig. 1 View of a 13-foot hull with no interior components visible. We do see a sink-style engine splash well, a long-thin rectangular bow locker, and the absence of any step pads in the bow quarter decks. There is no rub rail left to see, and the bow is not seen from head-on to assess if there is a "smirk". All of these elements are useful in determining the production epoch of a 13-footer.

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Fig. 2. View of a stencil number that is easily read as 2B8715. The gray hull color is probably due to under-exposure of the camera image, as the usual hull color would have been an off-white, not a medium gray.

102a.jpg (1.29 KiB) Viewed 484 times

Fig. View of the stripped-out interior with debris and dirt. The most interesting element seen here is the circular deck access plate.

103a.jpg (118.43 KiB) Viewed 484 times

BACKSTORY
I recently purchased a 13-foot hull planing to completely restore it for my grandson.

The hull ID on the legal title is BWCC 3365 M7 7E, and is presumed to be a 1977 model

The Stencil number is 2B8715

The boat appears to me to be a SOURPUSS, but my understanding is the SOURPUSS model production ended in 1975.

[jimh]

Q1: how can I determine the model type of a 13-foot hull from its hull Stencil Number or a number on its state-Issued title that looks like a federal HIN?

The stencil number does not encode any information about a model type. The federal hull identification does not encode any information about a model type. A number that appears on a state-issued legal title does not encode any information about a model type.

The stencil number can be used for production epoch dating, but in this case the stencil number 2B8715 is out of the known data range, which ends at 2B2700 in 1973. See the list in the 13-footer Reference Article at

The 13-foot Hull
https://continuouswave.com/whaler/reference/13/

Q2: how can I determine the model type of a 13-foot hull from other characteristics besides the numbers mentioned above?

The only source of model identification is from the hull appearance, particularly with its ORIGINAL INTERIOR COMPONENTS in place, with the assumption that however it appears now in 2026 after having been made in c.1977, that nothing significant in the interior of the boat has changed in those 49-years since it left the factory.

Since there are no original interior components seen in any of the illustrations, there is no basis for readers to infer any particular model configuration for this hull.

[jimh]

The hull ID on the legal title is BWCC 3365 M7 7E, and is presumed to be a 1977 model

There is no way to know if that number was the actual federal hull ID number that was attached to the hull with a metal tag. A more authoritative basis would be to find the metal tag or embossed lettering version of it somewhere on the hull.

Proceeding with the assumption that the HIN-like number is the actual HIN, and ignoring the unusual spacing of the characters, the decoding of the HIN yields this information

Decoding of federal HIN BWCC3365M77E

The Manufacturer ID code (MIC) is BWC which is the identifier for Boston Whaler company

The production sequence number is C3365
which corresponds to the correct HIN
production number sequence scheme for the 13-foot hull.

The letter M indicates this HIN uses the Model Year format.

The code 77 is the last two digits of the MODEL YEAR, in this case 1977.

The letter E encodes the MONTH of product as DECEMBER.

Because boats made by Boston Whaler in December were always sold as the next year's model year, this hull was sold as a model year 1977 13-footer, but was made in December 1976.

However, there are two elements that have been reported for 1977 production year boats, that do not appear in this 1976-production but 1977 model year boat. The first variation is the shape of the bow locker. The shape of the bow locker changed in c.1977 production to a more square-ish rectangle from a long, thin rectangle, and in Figure 3 we see that the bow locker is the old style long and thin rectangle shape.

The second variation from expected is there are not two step pads molded into the bow at the port and starboard bow quarters. There is just the thin gunwale section on this hull as seen in Figure 1.

On this basis, perhaps the "1977 production" for those changes began around July, which was typically when the model year changed to the coming year, in this case for model year 1978 boats.

[jimh]

The boat appears to me to be a SOURPUSS, but my understanding is the SOURPUSS model production ended in 1975.

You must be seeing something not shown to readers in your three illustrations, as nothing in Figures 1,2, or 3 suggest a particular model type.

The REFERENCE article on the 13-foot hull mentions the SOURPUSS was in production from 1971 to 1975. That model may have been omitted from the catalog listings after 1975 but perhaps a dealer could have possibly ordered a SOURPUSS version as a special order sometime after 1975. But again, the basis that this boat was a SOURPUSS seems very speculative at this point.

In the 1975 catalog the SPORT 13 is described as available in two variations: center steering or side-steering. To create the SOURPUSS model, you need to add to the center-steering SPORT 13 model a wrap-around stainless steel railing and a backrest on the helm seat, and add blue seat and backrest cushions to both the helmsman's seat and the seat forward of the steering console.

Fig. 4. Two models of the 13-foot hull as shown in the 1975 catalogue: a SPORT 13 with side steering, and a SOURPUSS 13 with center steering, wrap-around railing, seat back, and blue cushions. For c.1975, we see that the bow locker has not yet changed, nor have the step pads been added to the gunwales at the bow quarters.

SPORT 13 with side steering and SOURPUSS 13.jpg (69.76 KiB) Viewed 448 times

From a reader's perspective, we see none of those elements of the SOURPUSS in the photographs of the boat under discussion.

[Trmason1]

Thank you for your reply.

[jimh]

Q3: what makes you think this bare hull was once a SOURPUSS?