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Thread: 454 stuck valve, new heads? ('90 Black Widow 24' )

  1. #1
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    454 stuck valve, new heads? ('90 Black Widow 24' )

    Hey everyone, after a long day yesterday I finally got the motor apart and the heads off. The oil was white with water in the rocker area but I think it's just from condensation (visibly forming on rockers) dip stick is pristine as was coolant in passages, after lots of cranking for compression check.

    Low compression on most cylinders, from 50 to 131.. stuck valve = 0 psi obviously, but at least I know what the deal is now! That piston has a slight mark but seems to be okay.



    So, that leaves me with these gross heads - they're majorly rusted underneath and I think the valves aren't seating correctly at all which is causing the crappy compression numbers. The cooling passages are ~30% blocked with crud, and.. well.. they certainly look all of 2 decades old.

    Should I just trash these and get a set of Edelbrock Performer RPM Marine heads? ...or should I get these redone, and buy a cam kit with new timing chain, new lifters, and buy a nice set of rockers and pushrods. The casting number seems to indicate these were the vortec heads actually.. so I probably won't see TOO much of a gain in flow, which means I might be better off spending the money on nice valvetrain components and a nice cam.

    Does anyone know what cam or compression these 454s ran back in 1993 when Donzi replaces the Ford 460s w/ these? Details are sketchy to say the least. I'm trying to figure out what mods I can do and what kind of power it will give me - she came with a Torker II intake manifold, Holley 800 CFM, and SMI headers already (plus MSD blaster ignition). If it was running correctly before with a stock rating of 360hp (I think that's what it was) then I should easily near 400 with those mods.. hopefully rebuilt heads, nice valvetrain, and a cam can get me a nice bump in power as well.

  2. #2
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    I bet some of the guys on here will be able to give you some insight on the condensation issue. I would be surprised if the oil could turn milky while sitting from condensation. The oil should be separated from the water if it hasn't been churned by the crank. Since you have the motor torn down mostly, yo might have the block and heads checked for cracks so you arent wasting lots of time and money. If the block and heads come out with a clean bill of health, all you have spent was time. Then you can make a more informed decision on what would be the best place to spend your money. It would suck to spend money, only to find you have a crack in the block or a head you decided to keep.

    -My 2 cents

    --Nate
    Never Kick a opossum at 40 mph!

  3. #3
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    If you've got the money, sure - pop for the heads. Remember that you'll still need a few extra bucks with them though as they don't come with springs/locks/retainers.

    I'd also ditch that Torker II - low rise single plane intake? No thanks. I'd go with something a little more modern and a dual-plane design like the Performer RPM.

    The 800 cfm carb was likely more than that motor needed in stock form, but does give you lots of headroom to support mods.

    The $20 question is: What's your end goal? If you want to make 500 hp (or more...), you'll need some heads. If you just want a reliable powertrain that you'll maybe add a cam, intake, and exhaust to, the stock oval ports can just go to your local machine shop for a clean-up.
    Don
    '01 22 Classic, 502/B1
    And a bunch of other stuff

    "If everything seems under control, you're just not going fast enough" - Mario Andretti

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    I also think you need to look deeper into that milkshake looking oil situation..
    The fact that you had stuck valves and very poor overall cylinder compression along with that milkshake oil tells me that you have much more than just condensation going on there.

    You either have an exhaust cooling water reversion issue where water is being sucked-in the exhaust valves, leaky marine exhaust manifolds & risers, or a casting crack or rust pinhole porosity problem with one , or both, of your cylinder heads, corroded intake manifold water crossover water outlet passage, bad intake gaskets, bad head gasket/s or a rusted, or corroded engine block problem.

    Milkshake looking oil is much more than just a condensation issue.
    "BENCHSEAT 18" ~~YellowJacket~~ project owner~
    1929 Chris~Craft 28' Tripple Cockpit Mahogany Speedboat / A-120-A 845 Cu.In. 375 H.P. Chris~Craft V-8 racing engine.
    24' American Skier
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    1991 454 SS Chevy Super Sport Pick-up for towing my "Toys".

    There is no such thing as going too fast ~ ~~
    OR~ Being too old~ for a new "Toy"!

    Brad Hunter
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    what thermostat?


    Edelbrock ovals and a nice cam will really wake it up
    Charter Member - WAFNC, SBBR, KWOSG
    1955 Perfect Mate
    1986 Hornet III, 502-415 TRS

    www.donzi.org


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    Thanks for the comments everyone.

    As far as it not being mixed - I'm aware that water isn't readily absorbed into oil ( lol) but my thought process was that after cranking it for 5-10 minutes through starting attempts and later full compression check on each cylinder, anything could happen. I did see large drops of condensation, so I know that's happening for a fact. Oil pres went up to ~60 just cranking and seemed very good, and again the winterization coolant in the block was crystal clear as was the oil in the pan.

    Someone here mentioned that if the valve got stuck it probably screwed the guide and other things allowing water passage.

    zelatore - thanks, I too was wondering about that.. I need to check engine hatch clearance however since I'm wondering why they used the low profile intake anyways.

    Would you just match the performer PRM intake manifold to the performer RPM cam kit? And to answer your question, I've got a decent number of mods sitting here and if I freshen up the heads and put a cam in there, I should be at ~430hpish which I'm TOTALLY content with. I'm certainly not looking to push my luck with a 20 year old block (although I've heard stories of 454s in cruisers going 6000 hours). mid-level power but good reliability is what I'm trying to get, I'll sleep much safer at night with a good set of rockers/springs/pushrods and the newly matched valves and pristine heads

    I mean honestly I'll probably put 20 hours on it this season, and sell it to get a ZX or something. I got this as a project because banks weren't trying to touch anything old/expensive (ahem, donzi? haha) so I just threw some cash at something I could flip.

  7. #7
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    Thats good that the oil in the pan was good!!!!
    Never Kick a opossum at 40 mph!

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