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Mercruiser 3.7 Build, 1970 Cj5? Part 2, Fab And Adapting!

Discussion in 'Builds and Fabricators Forum' started by 70cj5134f, Oct 20, 2018.

  1. Dec 11, 2018
    wasillashack

    wasillashack Member

    Wasilla, Alaska
    Joined:
    Mar 17, 2008
    Messages:
    268
    Been following your build, very interesting. Been away from boats since '75 when I left FL to move to Alaska. I had a Correct Craft with a Mercruiser 4 cylinder 151 cubic inch engine, Chevy based I believe. These engines, while not as stout as your 3.7 would seem to be a good replacement for a 134 and enjoy cheap Chevy parts and healthy aftermarket support.
    Good luck with your project.
     
  2. Dec 11, 2018
    70cj5134f

    70cj5134f Member

    East Tn
    Joined:
    Aug 18, 2018
    Messages:
    749
    Alum block-volvo
    Cast head, pistons, rods, valve train -460 ford
    Flywheel Ford 80s small block
    Bell bolt pattern -GM
    Delco distributor
    Prestolite starter
    Fuel pump GM inline 6
    It accepts Ford 302 ballencer
    460 ford exhaust.
    This ant the same as the smaller GM 4cyl!
     
  3. Dec 13, 2018
    70cj5134f

    70cj5134f Member

    East Tn
    Joined:
    Aug 18, 2018
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    749
    Ran it again, with water in, bout 10 min. Starter still giving trouble,won't stay engauged,
    have to keep bumping it until it starts. Trying to locate the correct drive, local shop no help, napa no help, found several on line, but gotta pull mine back apart and take measurements.
    Puffing smoke when throttle slams shut, i did not like the stock umbrella valve seals, their huge ,guides were worn, but i wasnt wasting money on them,will upgrade to alum head if all works out. Ive ordered viton positive seals, should slow down the oil. No water leaks, retorqued head again. New points and condenser going in. Electric temp gauge ordered, it will fit the small water drain in block. Need to get all these bugs out so i can run it at least 30 min.
    Still impressed how little it vibrates, its on the equalivant of solid mounts.
    Benn busy with Holliday chores, may be a while to get a video up?
     
  4. Dec 14, 2018
    70cj5134f

    70cj5134f Member

    East Tn
    Joined:
    Aug 18, 2018
    Messages:
    749
    The damn points from eBay had green corrosion on the contacts?
    If full refund don't come, BAD feedback time.
    Stoped by Napa, showed my old set, my favorite counter guy, said that's a inline 6, gm points and condenser,
    Had them in stock, their now installed.
    Hope to get time to pull starter apart tonight?
     
  5. Dec 14, 2018
    Keys5a

    Keys5a Sponsor

    Florida Keys
    Joined:
    Jan 23, 2014
    Messages:
    4,170
    If I recall, the starter (and starter parts) was sourced from IH V8 Scout or Travelall.
    -Donny
     
  6. Dec 15, 2018
    70cj5134f

    70cj5134f Member

    East Tn
    Joined:
    Aug 18, 2018
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    749
  7. Dec 16, 2018
    Framer Mike P

    Framer Mike P Member

    Hopkinton, NH
    Joined:
    Jan 4, 2016
    Messages:
    217
    If both those starters indeed fit I would lean towards the scout one. I had a starter similar to the other one on my boat (OMC 3.0) and the ring gear for the gear reduction stripped its plastic teeth. This was on a boat - I would think there is much more potential to abuse a starter in a Jeep.
     
  8. Dec 16, 2018
    70cj5134f

    70cj5134f Member

    East Tn
    Joined:
    Aug 18, 2018
    Messages:
    749
    Well choosing a starter may be moot.
    Took mine apart 1 more time, payed attention to the wear marks on the spines,
    Reassembled , and it works! First startup, drive stuck out engauged with flywheel,
    Until it started, then a slight pop noise, and the drive went home and got quiet.
    Next startup it works as should. Kinda reminds me of my high school shop teacher,
    First day of class, he said to put stuff back like u find it.
    Ran it bout 35 min this time, no temp gauge, so I left the rad cap off , it would not boil.
    Got a little steam but no bubbles. Had a window fan strapped to rad, turned it off, still would not boil at idle and ocassional revving. No thermostat yet, I believe the stock cooling system will keep it cool, with a medium elect fan on rad.
    With new points and cond it really is a lot smother and easier to start.
    New valve seals going in, I'm using KW block seal next startup.
    Carb seems a little fat, no blk smoke, but I can smell it.
    Not at idle, but when above idle on the mains, but a boat is always under load, so I may have to lean the mains?
    Donny-any idea the stock timing, before they reduced it to 8 degrees btdc ?
    My book shows 8, I have it bout 12, but it wants more.
    When warm, no squirt, just bump the key and it starts.
     
  9. Dec 16, 2018
    70cj5134f

    70cj5134f Member

    East Tn
    Joined:
    Aug 18, 2018
    Messages:
    749
    .50 Vinton seals would NOT work on .55 guides.
    Steel bottoms.
    I had some .531 teflon seals from a previous build.
    Took apart, stretched seal over .58 socket, laid on stove a while.
    Spring ratainer gets opened up on a taper punch, and heated with a torch, not red just enough to change color.
    Cleaned guide with paint prep .
    Installed seal, then retainer.
    Only had 4 seals, enough for intake side.
    Hope to start and run with KW block seal before day over?
     
  10. Dec 17, 2018
    70cj5134f

    70cj5134f Member

    East Tn
    Joined:
    Aug 18, 2018
    Messages:
    749
    Pic for previous post. 20181216_171010.jpg 20181216_171010.jpg 20181216_170846.jpg
     
  11. Dec 17, 2018
    70cj5134f

    70cj5134f Member

    East Tn
    Joined:
    Aug 18, 2018
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    749
    During last night's 35 min block seal, the lower hose( part shop vac hose) sucked shut and split.
    Found a cb550 Honda pipe that made nice steel couplings for my scrap hose.
    Won't give trouble now.
    The pump has more power than I thought, I'll be keeping it as long as my speedy sleeve repair holds up.
    Took a simil ar carb apart off scrap shelf to get a couple smaller mains, came off a small gm v8.
    Mine had 66 mains, this one had 50s.
    I'm reaming them to close to 58s, the first edge of blue tape, rubber band at stock 66 jet.
    Hamb guys complained bout them being fat on the mains, several going to 2100 motorcraft
    ( I have 2 if I decide to go that rout.)
    Would rather tune the factory carb to suit.
    Still un sure on inital timing and advance cruve I almost believe I need to slow down the advance?
    Hope to crank tonight and flush KW block seal out?
    20$ e Bay elect temp gauge came in, it will fit my 1/8 threaded hole in block, mechanical sender won't fit.
    Slowly getting inital problems in check, i hope!
    1545087336224542918407.jpg
     
  12. Dec 18, 2018
    70cj5134f

    70cj5134f Member

    East Tn
    Joined:
    Aug 18, 2018
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    749
    Well sender too long, I'll have to put a 90 ell in then leave room for sender.
    Ran another 20 min and flushed. Still NASTY, at least one more flush.
    Still loads up if idling a while(3-5 min or longer) taking a fuel pressure measurement today, 3-4.5 spec. May have to lean idle circuit? May try enlarging air bleeds, found a dirt track build that does this .backed initial timing down to 10 dag BTDC, still 2 deg above spec.
     
  13. Dec 19, 2018
    70cj5134f

    70cj5134f Member

    East Tn
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    Aug 18, 2018
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    Fuel pressure 10 psi, way too high.
    Pressure reg next.
    Temp sender installed, had to run a tap through it to deepen the threads.
    Block flushed again.
     
  14. Dec 20, 2018
    70cj5134f

    70cj5134f Member

    East Tn
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    Aug 18, 2018
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    Regulator installed, new needle and seat, still pushing fuel at long idle periods?
    Back apart tonight. Check power valve and look for cracks.
    Going to lower float a bit.
     
  15. Dec 20, 2018
    70cj5134f

    70cj5134f Member

    East Tn
    Joined:
    Aug 18, 2018
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    Float set,1-1/4 stop, 1-29/32 drop, bout 1/8 in lower than previous!
    Power valve cha ked out ok.
    Ran a wire through all these holes!
    Opened the outside holes, just a tad.
    Inspected for cracks, none visdiable!
    Blew on fuel port at needle- seat, seemed to work correctly!
    Temp gauge hooked up for first time.

    Oil pressure benn 45 pluse. 1545354189356924031987.jpg 1545354225712821263081.jpg 15453542631331010982697.jpg 1545354289102318054179.jpg
     
    73 cj5 likes this.
  16. Dec 21, 2018
    70cj5134f

    70cj5134f Member

    East Tn
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    Aug 18, 2018
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    749
    Oil pressure ,30 at hot idle, 50 with rpm.
    Temp 195, no fan after idle 30 min.
    Temp 185 with fan on at idle.
    No thermostat yet.
    1545438902844415596270.jpg 1545438943511696260633.jpg
     
  17. Dec 21, 2018
    Jw60

    Jw60 Sitting up n buckled down. 2024 Sponsor 2023 Sponsor 2022 Sponsor

    Sedalia MO.
    Joined:
    Apr 8, 2008
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    4,716
    Small recorded sequential changes. Keep up the good work. Looks like you will have it ready for a Transmission soon!
     
  18. Dec 25, 2018
    70cj5134f

    70cj5134f Member

    East Tn
    Joined:
    Aug 18, 2018
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    749
    Hooked hot water to one end of intake, for test, it warmed up in bout half time 20 min till intake warm to hand touch.
    Going to tap intake (blue tape), for 3/8 pipe thread ,and send hot water to intake.
    Don't need much flow, need the heat!
    Merry Christmas everybody!
    Got a new wallet for today?
    Mines been thread bare 6 monthhs or longer!
    After Christmas shopping, I ant got nothing to put in wallett??!!
    LOL!
    1545772344131508667386.jpg 15457723898881447656840.jpg
     
  19. Dec 26, 2018
    70cj5134f

    70cj5134f Member

    East Tn
    Joined:
    Aug 18, 2018
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    Home reamed , 1545856249769786831558.jpg 51 mains installed.
    Hot water entering rear of Intake, 1/2 in line.
    Exit front of intake ,Teed into radiator return hose.
    (Hope to tidy that up with 1/2in line when install in cj).
    Family coming for meal tonight, might get to test jet after meal?
     
  20. Dec 27, 2018
    70cj5134f

    70cj5134f Member

    East Tn
    Joined:
    Aug 18, 2018
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    Warms up in 5 min now.
    No smoke or stumble then.
    51 mains close.
     
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