2008 150 Sport Minn Kota Quick Release MKA-21

Repair or modification of Boston Whaler boats, their engines, trailers, and gear
wldrns1
Posts: 7
Joined: Tue May 26, 2020 8:34 am
Location: Central New York

2008 150 Sport Minn Kota Quick Release MKA-21

Postby wldrns1 » Fri Nov 05, 2021 12:56 pm

Before I proceed, I'd like a second opinion.
Some Info:
Installing Terrova 55 with Quick Release MKA-21
I do not have a bow rail. Side rails only. Fresh Water use only.
I have never had a piece of phenolic in my hands so can't judge it's integrity.

Does anyone know if Richlite was the phenolic manufacturer for that used in my model year? I could get samples to test. Richlite not mentioned here in New Forum, just the Old. I see a 1/2" piece in bow location 'E'. Same is also used for ladder at 'ZA' and bow cleat 'G'. Model diagrams both show 1/4-20 at these locations. Any thoughts on suitability of using the 3/8" phenolic bow locations?

My manual pg 2-6 says 'Drill & Tap' for trolling motor bow install. Minn Kota MKA-21 uses nuts underdeck for attachment of the Inner Plate.
I contacted both Whaler and Minn Kota for install suggestions/details. Not complaining but each party referred me to the other. Neither wanted to get involved. Unfortunately, not helpful.

I'm hoping to mount the MKA-21 Inner Plate permanently to the the bow step area (have to raise it with a 1/2" Starboard plate due to the rub rail). Per my manual, the bow is reinforced for this purpose. I'm surprised at the lack of help from both OEM's. I talked with front line customer service people at each. Each did ask other people but sadly no suggestions. I did read this and Whaler Central Forums but not finding answers there.

Any Center Plate mounting suggestions (hole size/fastener type/0.5 vs 0.375 phenolic) would be GREATLY appreciated.

Thx,
Joe

Mspbadger
Posts: 1
Joined: Tue Aug 27, 2019 12:12 pm

Re: 2008 150 Sport Minn Kota Quick Release MKA-21

Postby Mspbadger » Wed Mar 11, 2026 10:54 pm

[Moderator's note: this thread was dormant for five years with no replies. Soliciting responses from the originator of a thread that is five years old is always a bit sketchy.]

I’m considering [something similar that was mentioned in this article five years ago but is left to the reader to figure out exactly what is being proposed].

My only experience with Phenolic so far is to break a tap in it.

I have a 2005 [apparently means a 2005 150 SPORT]. I believe [the backing material in my boat] is wood. I presume from [model year] 2006 [and afterwards] there are reinforcements in new places because the [150 SPORT] hull was shared with the [150 MONTAUK].

jimh
Posts: 13285
Joined: Fri Oct 09, 2015 12:25 pm
Location: Michigan, Lower Peninsula
Contact:

Re: 2008 150 Sport Minn Kota Quick Release MKA-21

Postby jimh » Thu Mar 12, 2026 11:11 am

The term "phenolic" as used here most likely refers to a material like G10 fiberboard.

Cf.:
G-10 Material
https://en.wikipedia.org/wiki/G-10_(material)

The original use of G-10 was in electrical circuits, where its insulating characteristics (remaining a non-conductor) were important, as well as its strength.

Regarding using a tap to create a threaded hole in G-10 material, the best results come with using very sharp carbide tools and proper taping techniques.

The hardness of G-10 is cited as Rockwell 110. As a comparison, Aluminum 6061 material is rated Rockwell 60 -70, aluminum would be much easier to tap.