Thanks Thanks:  0

Thread: Fast Fred's Secrets of the OMC MOD50's Thread #1

  1. #451
    Team Member
    Join Date
    Nov 2008
    Location
    Horseshoe Bend, ID
    Posts
    657
    Post Thanks / Like

    Default More thoughts

    Hello Sam,

    There are about 5 hours on new gears so far and the oil is clean. Having run FE for years, it was the only case to choose. It's been bulletproof under the 45 and my FE triples, parts are readily available, and props in a useable pitch range are plentiful. The power won't hurt it too bad for laking.

    With the quiet tower, noise isn't a problem. But, the Sheriff can tell the difference between 55 mph and 100! With it's ferocious acceleration, you chew up alot of lake and can't stay out too long. So, durability isn't an issue. Even if they last only 25 hours, the ride will be worth every penny!!!!

    Tim

  2. #452
    FFX-61
    Join Date
    Aug 2005
    Location
    Stellwagan Ledges
    Posts
    1,389
    Post Thanks / Like

    Default

    you got cast in liners or pressed in, in that case your runnin?
    nice rig.

  3. #453
    Team Member
    Join Date
    Nov 2008
    Location
    Horseshoe Bend, ID
    Posts
    657
    Post Thanks / Like

    Default Sleeves

    Hi Fred,

    That would be the real McCoy pressed sleeve two port. Was collecting parts for about 10 years to pull that monster together. It proved well worth the wait! Here's the business end.

    Tim
    Attached Images Attached Images  

  4. #454
    John (Taylor) Gabrowski
    Guest

    Default I keep hearing OMCs and 25 hours for 3 Holers?

    Tim:

    I have a new 3 Holer OMC 49 cubic inch replacement complete block with innards and all that I bought with an entire blown up short shaft fishing engine at a neighborhood garage sale a little over a year ago now. I have been reluctant to tear it down just to put some other aftermarket pistons in it as opposed to keeping the new factory pistons in it now. I keep hearing this OMC 25 hour life span rumor stuff of some kind tossed around that such a new engine will last until what starts happening? Irregular wear, bore goes out, pistons wear out?? I am new to OMC 3 Holers specifically after being tortured by 3 Holer Mercs and Mariners that really jaded me and these 3 Holer 49 inch OMCs are sure no Merc so they all must have some stories and pointers to go with them all their own I know little or nothing about. Want to share????? Everyone???

  5. #455
    FFX-61
    Join Date
    Aug 2005
    Location
    Stellwagan Ledges
    Posts
    1,389
    Post Thanks / Like

    Default

    gots me one of them McCoys, gots the part number for the sleeves?

    25hrs????????????? , thares a Stinger 65hp at the shop, thay got it New back in the day, got way more than 25hrs on it.

  6. #456
    Team Member 850cc racer's Avatar
    Join Date
    Sep 2005
    Location
    australia
    Posts
    220
    Post Thanks / Like

    Default

    ive just found x3 of these fred .. this one has had a BOOM at some stage looking at it
    Attached Images Attached Images  

  7. #457
    Team Member
    Join Date
    Nov 2008
    Location
    Horseshoe Bend, ID
    Posts
    657
    Post Thanks / Like

    Default 25 hour lifespan

    Hi John and Co.,

    The 25 hour life limit is about right for of my best blister-sleeve FE engines. It should be noted that's the equivalent of 5 seasons racing mostly at wide open throttle. During this time the engine is expected to be flipped at least twice, run on bad gas with worn spark plugs, and occasionally starved for fuel, cooling water, or lugged (the worst possible conditions). Considering these engines were designed for 70 HP at 6000 RPM and are delivering more like 95 HP at 8500 RPM, what do you expect? My developmental engines were lucky to make 10. The 20+ pistons in my "offerings to the God of speed" box tell stories, along with my engineering & testing notes.

    The single most important thing to remember is a high ported OMC loop triple requires tandem vacuum pumps or an electric. Fuel starvation is your #1 enemy followed by loss of cooling water. Daring souls will run pumpless. I wouldn't run one without. So,

    If your powerhead has new factory pistons, and you race it hard, run it for two seasons, tear it down, and crack check. If you only run occasionally for fun, don't worry, the cast pistons usually just break a skirt off, blow chunks through the thin case with little or no damage to the engine otherwise. A little welding, a new piston, and voila' you're back on the water.

    Good luck!

    Tim

  8. #458
    Team Member 850cc racer's Avatar
    Join Date
    Sep 2005
    Location
    australia
    Posts
    220
    Post Thanks / Like

    Default

    Hi Tim, what fuel pressure have you found works best? using electric pump

  9. #459
    John (Taylor) Gabrowski
    Guest

    Default Electric Fuel Pump with a Holley regulator??

    Tim: I take it that 2 OMC fuel pumps looping through the 3 carbs is playing it fail "safer" than any single pump. I have some experience with Holley 12 volt pumps and fuel pump pressure regulators as well as Dupree 12 volt pulse pumps too from playing with turbocharging smaller automotive stuff but nothing on outboards. Stick to a minimum of 2 OMC fuel pumps?? Somewhere I heard that these OMCs also bring in water for racing different than stock fishing use. Is that adding on an extra line opposite each cylinder through the water jacket outer including what comes up the base? I am hearing that OMCs from 35 horsepower and up heat up real fast.

    Actually from that 25 hour description that is taking a pounding at high rpm no fishing version would be put through is pretty dang good alright. Being a Merc fanatic (excluding 2 carb 3 holers) early on and for so long gives one false opinions based on the older non-loop OMC engines where I as others would term them being worked on by the hammer, screwdriver and crescent wrench crowd. Seeing what is going on these days on those and your engines by example would get one a poke in the eye or a vicious clubbing about the head for expressing such sentiments anymore for sure! LOL! Now I find myself being the enlightened and converted!

  10. #460
    FFX-61
    Join Date
    Aug 2005
    Location
    Stellwagan Ledges
    Posts
    1,389
    Post Thanks / Like

    Default

    you are a long way from a 25hr life span with a stocker or a Mod Stinger,
    the one ring Mod50 piston, the long rod makes piston speed faster, the BTUs made, ya a long ways.

    it cool to see all three units, the 19s, the Straight-in, and the 31m.

    any body gots a set of liners?

Thread Information

Users Browsing this Thread

There are currently 2 users browsing this thread. (0 members and 2 guests)

Similar Threads

  1. Quincy Welding Speed Secrets Revealed
    By Original Looper 1 in forum Outboard Racing History
    Replies: 15
    Last Post: 03-02-2007, 04:33 PM

Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •