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Sign Reads "Wanted: Good Woman Must Be Able To Clean, Cook, Sew,  Dig Worms, and Clean Fish.  Must Have Boat and Motor. Please Send Picture of Boat and Motor.


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If your Mfgr. says:

That motor's 7 years old!!
Part is no longer available.
We lose $$ on service!
EPA made me do it!
Part's at central warehouse, you'll get it next month.
We don't make parts for those.
We only do warranty work.
Our techs only fix late models.
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You thought I was kidding about all those restored B Mercs? Well, here's photographic proof that they exist. And there's a thumper and one more totally original one not in the photo. Look close at these, this is NOT a trick photo. Some have short skegs, some long. Some have steering bar bolts, some don't. These thumbnails are links to bigger scans, so click your mouse on 'em to see the real picture.


For those of you who haven't a clue, this motor was developed by Mercury in 1954 as a replacement for the KG-7H "Hurricane", as the competition was fierce in class "B" racing, and they were getting beat! It has a similar cranktrain to the Mark 25 service model introduced in 1955. However it used unique components for most of the powerhead parts, not shared with the MK25. Originally equipped with a Carter model "N" carburetor.

Champion motors developed a racing "B" called the "B hot rod" that soon eclipsed the 20H, so Mercury engineering got busy and developed a revision to this motor titled "new carburetor and accessories". The "accessories" consisted of a new fully tuned exhaust. This noisy item soon earned the nickname of "thumper". This motor just died out with age, as the parts sources dried up, and race sites banned the noisy critters. The motors seen here are mostly "de-converted" with this tuner removed. Several are originals though. This model is very collectible right now, as all those old dudes (like me!) that raced 'em are wishin' they had'a saved one - -

There has been a renaissance of the old "B" class runabouts using these 20H motors as well as the other contemporary models of the 50's. Under APBA rules, boats and motors must comply with the rules then in effect.

CREDIT must go to Charlie Williams of Performax Marine in Puyallup, WA for spending the time and effort to restore all these to as close to original as possible. He can be contacted at OUTBOARDRACING.COM. The rules for "Classic B" may be found there as well.



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