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first post... simple questions I think.

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  • first post... simple questions I think.

    Hi all,

    Quick background... midlife crisis age I built a variety of sea-fleas and things as a kid, and in high-school - a Clark Craft CU-42 to B class specs. I went through a variety of engines but ended up with a bunch of Merc 20H stuff. I never raced the boat in any sanctioned events... Just played. We had a few on the lake, enough to have some memorable moments.

    Life happened... I did other motorsport things, and other things in general.

    I have no intent on running sanctioned events, just want to get the boat back up and running (Partly so my dad can see it go again before he can't...). The boat itself needs work, but that's not an issue. A week of evenings and it should be back in shape.

    However, while 30 yrs ago I could confidently pull a motor down on the beach and replace whatever and go back out. Now I'm more hesitant, and the supply cabinet is smaller, I don't want to make any mistakes.

    Here's kinda what I have:

    Couple 1:1 lower ends, (edit! 16:21 gears! )
    too many 10 drilled hole mid cases
    Several blocks and a few lower ends without rod exit wounds
    Couple of good cranks
    enough pistons and rods
    Plenty of angry pixie control units
    A real corn-popper mid case! (I really want to run this, the noise may be too much to bear on "the lake" even on short runs, but **** the torpedoes)

    So really enough to build a motor (maybe two)...

    My google fu is normally pretty good, but I can't find a general spec manual/page. l I have rods with different widths, some length differences, lower ends with various different fuel pump arrangements. Has someone produced the venerable "guide to all things". I figure in the real racing world, someone may have put something together.

    Sorry if I missed something obvious here on this site. I spent some time searching around, but haven't found it yet.

    Thanks for your help! Looking forward to this little project.

    Oh and great to see an active BBS type forum!!!


    Last edited by madmattf; 05-18-2022, 10:28 AM.

  • #2
    Matt, welcome to www.hydroracer.net ! Sounds like you had a great time with the old racing engines and you've come to one of the right places to get help putting your gear back on the water. There are as many options and opinions about what parts to use as there are grains of sand on the beach, but one older guy, George Stillwill once had as close to the "guide to all things" you mention. His website is long gone, but you can access most of it here on the ole Wayback Machine: https://web.archive.org/web/20091021...bsh/index.html

    George & his father concentrated on the A class KG-4 engine, but his build techniques, parts used, and tips would apply to your 20ci engine build as well.
    Maybe mention your location/where you live now, Matt, and there could be help for you locally?


    • #3
      25xs, Thanks for the warm welcome! I spent some time this morning (when I should be working...) poking around again, and started to find more info, it's about finding the right rabbit hole! Thanks for the George Stillwill stuff! That's exactly the sort of thing I was looking for. Also found JohnsOldMercs this morning too. I have various lower cases with various sized carb inlets (some I remember modifying myself, but some is foggy...) etc.

      I actually just spun a lower end I have on hand here and it's a 16:21!

      I'm in Montreal, but the boat and most of the "stuff" is north east of Parry Sound Ontario. I have a couple of blocks and the complete drive train with the corn popper here... enough to get me started (at least remembering what all this stuff does) until I make it back in a few weeks to get more of the "stash"

      Edit... 25xs! YES the https://web.archive.org/web/20091021...bsh/index.html is awesome! Even just reading through the build up process quickly. Lots is coming back! oh fun!
      Last edited by madmattf; 05-18-2022, 11:00 AM.


      • #4
        Welcome to the site. I've stood next to a popper helping them launch and the noise is really something. That being said if your neighbours are understanding and you're only going out a few times a summer...It would be a shame to leave those parts on the shelf.


        • #5
          Ok Matt, now you can go surf here: https://aeroliner-boats.com/ https://outboardracing.com/ Look at these collections and check out the reproduction parts for racing as well. There is a HUGE fanbase of old racers and "racer wannabees" out here. I fall in between those two! You mentioned www.JohnsOldMercurySite.com as well and that's a great wealth of knowledge. Just keep in mind these are 100% volunteer sites with some of the best racers & engine builders around, but you can't expect immediate answers or parts offers. Some guys don't check these sites but every few months. Best to use the "SEARCH" function on any site you find and see what you can learn on your own from the old posts before asking a question that has been answered many times.

          Another suggestion is to have the Quicksilver racing gearcases inspected and rebuilt by a reputable person rather than trying yourself. It's well worth the money and they just don't build them anymore. The gearcases are the 'weak link' in these old race motors and it's important to treat them well and learn to service them so you don't break them.


          • #6
            How did I miss finding https://outboardracing.com/ !

            Really what I needed was the "what do I have on my hands" answered...(and you have already helped tremendously! ) I was going to post pics, but I only have the 2 blocks here... the real mess is a ways away, and I need to bring it home (discretely as tool/stuff creep is an issue in my small shop that is supposed to be shared with the rest of the family! ), but moving forward!

            No immediate responses expected! And that's why I was looking for page resources too... so as not to keep coming asking more one liner questions, although sometimes that's part of the fun right!

            I think some of my early search issues were my recollections I was searching for "Hurricane" stuff because that's what I remember calling it, and, and stumbling on mostly "old outboard" sites without the hydroplane/race boat slant, and when I went that way, it was youtube vids of rebuilds by folks like me (just enough knowledge to get get in trouble)... with no specs. Fun to watch, but...

            Yes re the lower ends. I'm a hobby machinist, and have some decent tools to measure and check tolerances, backlash etc., but knowledgeable eyes and hands can't be beat! As I dig into it more is coming back.

            Anyway, really getting quite excited about this. It's been collecting dust for too many years, and I'm too busy with other things, but sometimes we just need to dive in and get it done.

            Here are a few pics though for fun!

            First is a screen shot of a vid I took... I already pulled the motor down, so nothing better and long story, but that motor was displayed at a boat show minus much of the internals... cobbled together to "look good", but that was ahhh... over 25 years ago!
            Click image for larger version  Name:	Screenshot_20220518-175945_WhatsApp.jpg Views:	0 Size:	246.3 KB ID:	479600

            Next ones are from a head that I actually tried... I got a bunch of stuff from "a guy" that was a notorious tinkerer, and he had built expansion chambers to fit this contraption, but no longer had them. For giggles I remember putting this on a drive train and ran it with the exhaust like seen! made no power... but was almost as load as the corn popper... now taking it apart I'm amazed at the effort that went into making that exhaust splitter! Looks to be done with stick welder, a file and maybe a grinder? anyway, that's another "good" rotating assembly but I'm not sure yet what the reeds or reed cage is.

            Click image for larger version  Name:	20220518_183503.JPG Views:	0 Size:	829.5 KB ID:	479601 Click image for larger version  Name:	20220518_183524.JPG Views:	0 Size:	735.0 KB ID:	479602 Click image for larger version  Name:	image_43097.jpg Views:	5 Size:	842.0 KB ID:	479599
            Attached Files
            Last edited by madmattf; 05-18-2022, 04:30 PM.


            • #7
              The Beaver Lake Regatta, planned for July 25 and 26, 2020 at Erinsville, ONT is a great place to reconnect with old racing friends and enjoy a racing weekend in Eastern Ontario! Check out " Old Boat Racers and Friends Reunion Weekend" on facebook. Should be about halfway for you.

              They will be running 20H's there and there will be people who know how to build them.

              They rune 20H's at a September race at Crystal Lake, Redwood New York . Not too far from you. Some good engine guys will be there.


              • bh/
                bh/ commented
                Editing a comment
                TORC, the Toronto Club. is running a race @Tweed, ON, an hour west of Beaver Lake, on June 11-12. MLAOC, {antique o/b's} will be there also. A dozen or so TORC guys run poppers, or try to ! (bh/)

            • #8
              Just thought of boatsport.org. They have Harry Brinkman's manual. Lots of info on engine building.


              • #9
                Harry Brinkman's manual...


                YES! Gold. THANK YOU!!!

                I own Bill Fisher, and Bob Waar's "How to modify your datsun engine" And even though I have never been inside a Datsun engine (i did briefly own a 240z...)... it was a gold mine. A quick glance over Harry's manual, and this is amazing.

                I measured my 2 heads I have here, last night, one is 20 over, the other 30 over! (the one with the crazy exhaust ports). The corn popper was running 700 827 pistons, the contraption was running 718 1193's those piston numbers took me on a deep dive into merc pistons. Skirt, rod to deck hights look similar, but the casting is very different with the 718 having way more volume, and no "flame cut" ( I'm not really a 2 stoke guy at this point) through the exhaust side.

                Much reading to do on Brinkman's book!!!!

                oh fun!