Stumped…AGAIN, 1962 OMC 10hp

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Viewing 10 posts - 21 through 30 (of 46 total)

  • jeff-register

    US Member - 2 Years
    Replies: 1564
    Topics: 54
    #36826

    Mr Beerman,
    My 1979 Cadillac pinged like crazy on regular gas & needed to run premium grade fuel. That car has vacuum hoses everywhere. I replaced every hose on it & it ran like new on regular fuel & NO pinging!
    I also have a 1958 Johnson 18 that was stumbling. Replaced the top seal & oil line to top bearing & cleaned up the mag & contact areas. Never had a bump or wet powerhead ever again. Please do not give up & sell it. Replace the shift shaft seal, top crank seal & oil lines. It will purr for you. If not get a spray bottle of premix & run it at idle. Spray a little fuel on the crankcase halfes & if it speeds up it is leaking.
    ATTACK it like a new motor for your collection. It will run very nice, I know you know how to get it right!!!


    jeff-register

    US Member - 2 Years
    Replies: 1564
    Topics: 54
    #36827

    Way to go it runs good now!!!
    Jeff


    beerman57


    Replies: 596
    Topics: 126
    #36841

    It ran great, not ever one sneeze in 6.5 hours of break-in, mag plate bone dry. I already have a buyer for it, but how do charge what it’s worth if it covers the powerhead with raw fuel. Upper and lower cowl, powerhead all clean and dry again, we’ll see in a couple days. Jeez, I’ve got another 10hp to get running, if it gives me any trouble like the last 2…………..


    beerman57


    Replies: 596
    Topics: 126
    #36928

    Major bummer for me!!! It’s the split in the block halves. Got it back together and fired it up on the hose in the driveway, saw it leaking this time near the top on starboard side. Now it is a small leak there, but warm, raw fuel and water (I think) were coming out of the lower bolt for the motor mount on that side – then it started dripping off the bottom of the shift handle where it comes out of the midsection. Now I’m pretty darn sure I used almost brand new anaerobic sealer from NAPA on the block. That seems like a LOT of fuel coming out of those other places and I went through 6 gallons of gas in 6.5 hours of break-in (80% – 85% idling). That does seem like too much, right? Man, I’m pretty darn careful to do things right when assembling a powerhead. So what did I screw up, or what is wrong with this block? I know, I know, disassemble and find out – well I’m about done with this damn motor for now. TIRED of everything going wrong on these 10’s, that QD19 just before this with the hot midsection. IT JUST GETS OLD!!


    Mumbles


    Replies: 5764
    Topics: 298
    #36938

    The anaerobic sealer should have worked unless there was some oil or grease on the two halves but there is a fix if you don’t want to split the cases again. If you can get into the leaking area with a dye grinder, rough up the metal and degrease it with lacquer thinner or something similar. Apply your favorite epoxy compound and let it harden up for a day or two before touching up the area with matching paint. No one will ever know. 😎

    As for the outside mounts, on the CD and AD models, one screw goes right thru into the exhaust chamber and needs some sealer on it to prevent that leak. The QD and FD motors might be the same but I can’t remember.


    fleetwin

    US Member - 2 Years
    Replies: 4737
    Topics: 46
    #36942

    OK, there is raw fuel on the powerhead, and dripping off the shift handle, correct? I’m thinking the raw fuel is dripping down the powerhead, then leaking out onto the shift handle through the lower motor pan. You have replaced the recirc hose and fuel pump with no change. I feel responsible for this mess if I unloaded the powerhead on you. Did you split the crankcase halves? If so, I am thinking there is a slight external crankcase leak. Yeah, I know you would think a leak would affect the idle, but maybe it is slight enough not to have a big effect. I guess I would wash the powerhead/shift handle off with some sort of soap that will dissolve left over fuel/drool and let it dry. Next, you might try running the engine after sun set and watching that area with a timing light, the blinking light in the dark might just catch a fine mist/vapor leak that is much tougher to see in the day light.
    Refresh my memory and let me know just what I sold you, complete powerhead, empty crankcase?? Blue or white??


    beerman57


    Replies: 596
    Topics: 126
    #36948

    Don, It’s probably something I did or didn’t do, especially if this block didn’t have this problem before. But now I’m really stumped by this fuel coming out of motor mount holes and the shift arm through the midsection. The leak between the block halves is very small, I’m just so confused – where is all this fuel coming from, out bolt holes and shift arm thru the mid – a whole lot more compared to the spit coming from the block split. Like fuel running out the bottom of the block and being washed out any tiny opening by exhaust water and gas? This thing runs perfect, it does take 5-6 pulls cold, but will idle down to where you can just about count the rpm’s and has good get up and go – never sneezed once. So now, after running for about 5 minutes till I finally saw a spit of fuel from the block split – the block is still clean and dry, a tiny bit of fuel at the top of the block split, but fuel basically pouring out the midsection openings, I mean a lot.
    It was just a bare block, white (Johnson?) For the last 3 hours of break in, I was/am going to run my 10" pitch prop and I’ll bet it would push my 13′ Feathercraft 23mph. Both of my QD11 (70psi) and QD19 did.


    fleetwin

    US Member - 2 Years
    Replies: 4737
    Topics: 46
    #36961

    At this point, I would take Mumbles’ advice. Locate exact leak area, use the die grinder and epoxy sealer. The engine runs so nice, would be a shame to pull it down again. It is possible that the block is slightly porous, and the leak has nothing to do with your sealing job. I know my 10hps leave a pretty good oil sheen on the water, but I just attribute that to the 16:1 mix I use. You already pulled the powerhead back off once, correct? Did you replace the shift lever oring? Go ahead and use some heavy duty sealer on those mount bolts like Mumbles says….


    beerman57


    Replies: 596
    Topics: 126
    #36965

    Just one thing though, that is a heck of a lot of unburned fuel coming out, really too much to ignore I think. Where can all that fuel be coming from? The carb and reeds should only be allowing in a little more than the motor needs, right? It’s not running lean and if I had it way, way too rich, it would bog down when I give it throttle and not idle down too? Do the epoxy thing and see how far I can lean it out, I guess. I just can’t figure where all that fuel is coming from, a gallon an hour at idle probably 85% of the time seems like way too much fuel consumption to me. I should be able to run all day on a plane with 6 gallons, shouldn’t I?


    Mumbles


    Replies: 5764
    Topics: 298
    #36971

    There’s also at least three manifold screw threads on the front of the motor which are drilled thru into the crankcase. These need sealer on them to to prevent any leaks. Especially if they have the factory star washers under the bolt head which I think your ’62 motor might have.

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