blown head gasket?

Discussion in 'Street/strip 400/430/455' started by buickbill, Sep 3, 2018.

  1. buickbill

    buickbill Well-Known Member

    anyone have exp. with a blown gasket on a 455 . water is coming out of the pass side frnt cyl. .I guess that would be #5 exhaust port very fast .does that sound like a head gasket , or something cracked . havnt torn it apart yet. mtr. runs good aside from pouring water out that port . do these mtrs have a cracking history , block or heads . or do the gaskets fail first. mtr. was running warm as a result of no fan shroud .fixed that .seemed to be running cool ,then suddenly the water started pouring out as I said
     
  2. GSX 554

    GSX 554 Gold Level Contributor

    Passenger front cylinder would be #2 cylinder . Cracked head ??? possible
     
  3. hugger

    hugger Well-Known Member

    I've taken apart a good many with blown gaskets
     
  4. Stevem

    Stevem Well-Known Member

    Your talking about water here and not coolant?
    If the motor was running hot and you gave it cool water, then yes that shock could have blown the gasket and or cracked the head.
    Either way it's head removal time!
     
  5. Bens99gtp

    Bens99gtp Well-Known Member

    How much volume of water/coolant are we talking.

    I've seen the walls get pinholes in them.

    Any thing in the oil

    Best bet is to pull the head look at the gasket for a failure, have the head checked for cracks
     
  6. Stevem

    Stevem Well-Known Member

    If you have no steam coming out the tail pipe then chances are good that it's just the gasket.
     
  7. lemmy-67

    lemmy-67 Platinum Level Contributor

    When I bought my Buick in 1994, the 430 had a blown head gasket in-between cylinders 3 & 5, water jacket to outside. No water in oil, but couldn't hold any coolant pressure. Heads and block were fine. Had it towed up to the Bay Area, and top end was torn down & rebuilt with new gaskets/seals. Ran great.
     
  8. buickbill

    buickbill Well-Known Member

    thnx all , I quit putting it off ,and pulled it . blown at the frnt watr jacket on the head . didn't appear there was any cracks . heads back on, waiting for torqe .. used never seize on bolts . don't need silicone ? first time ever tearing in to 455 . engineers did grt. job .! fun , and simple ,to work on . nice not to even have to deal with the dist. ,at all . and 4 bolts for the rockers , no adj., how much better can it get!!! now if it works . only pulled one side . we will see !gona reuse valley pan . good/ bad/ ugly . seems in good condition !?!?
     
  9. Mark Demko

    Mark Demko Well-Known Member

    Use a new valley pan gasket:D
     
  10. buickbill

    buickbill Well-Known Member

    should I use silicone on valley , or dry .
     
  11. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD" Staff Member

    matt68gs400 and lemmy-67 like this.
  12. buickbill

    buickbill Well-Known Member

    thnx larry .same thing my parts guy said . no new gasket in stock, 3 day wait . I guess I shouldn't even think of trying to reuse ?
     
  13. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD" Staff Member

    You can reuse the metal gaskets as long as they are in good shape. Just clean it really well. Spray around the intake port section top and bottom with copper coat or high tack. Put a thin coat of RTV around the coolant ports, top and bottom of the gasket. RTV in the corners where the rubber seal tucks under the heads.
     
  14. Mark Demko

    Mark Demko Well-Known Member

    Im old enough now to say "back in the old days" Fel Pro use to include the dark blue goo for the intake ports, and a small tube of black RTV.
     
  15. buickbill

    buickbill Well-Known Member

    well all would be fine now , but my rad. isn't up to the task . need one that will keep me from doing the head gasket again . what rad. will fit in my 64 special ,that will go in easy , and keep it ice cold . I NEVER want it hot again . mtr. ran 160 yesterday morning . thought I was good . drove it in the afternoon ,and it hit 240 before I could get home . like I said . never again. has a aftermarket vertical alum. now . should I switchto horiz., while im at it? would prefer it to look as stock as poss. . as stock as a 64 special with a 455 can look anyway . but will use whatever does the job . also , mtr has gm hei dist. and I have not enough room with pwr steering ,and edlbrk. mnfld. what dist . gives me the room I need .not a race car , just a daily driver toy
     
  16. Bens99gtp

    Bens99gtp Well-Known Member

    A mallet or msd dist are smaller caps. Ate you wanting to run the vac advance??? You could pair the msd with a 6520 box and lock the timing out so it has full timing at idle this will cool it down some.

    Not sure your radiator size. Wizard cooling makes a radiator for 65 Olds 442. They make both a 15.5 and 17.5 core, they use 2 rows of 1" tube or 1.25" tubes. Not sure if it would fit your car or not.

    Some radiators are several rows of 5/8" tubes......as is the case in this olds, the have a 16" bolo fan in and a shallow shroud. Won't stay cool at all. I think with than being offset in the case it leaves a good part of the radiator with no fan and the shallowner shroud doesn't let enough air through when going down the road. The hose temp coming out of the radiator basically matches what going into it.

    The smaller tubes have the water pass through them faster plus there is less area for the fins.

    Does yours have 2 fans or just 1
     
  17. buickbill

    buickbill Well-Known Member

    I just have 6 blade /shroud , but I doubt any fans would keep it cool .had the thermostat off and drained the rad.,might have had some wtr in the block ,but not much . filled it with 2 gallons . so way to small!! 25wide 22 tall core is only 1.5 thick 2 rows im guessing . cant see very well
     
  18. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD" Staff Member

    Ignition timing can make a big difference in engine coolant temperature. Unfortunately, lots of guys have no idea what their timing is, nor how to even check it:). Vacuum advance can help.

    aluminum radiators are useless if they have small tubes (1/2"-5/8"). A brass copper with the same size tubes would actually be better. Any aluminum radiator you plan to purchase should have at least 1" tubes, preferably 2 rows.
     
  19. Schurkey

    Schurkey Silver Level contributor

    1. No aluminum radiator is going to look "stock".
    2. Crossflow radiators have a natural advantage over downflow radiators--the rad cap is on the outlet tank instead of the inlet tank. Dynamic pressure from the water pump tends to overload a rad cap on the inlet tank, whereas dynamic pressure from the water pump reduces pressure on the outlet tank--so system pressure is inherently higher even with the same static pressure rad cap.
    3. Timing, fuel curve, coolant flow, and airflow management are all really important for cooling ability. Don't immediately jump to a replacement radiator without inspecting the rest of the system.
    4. Street-driven? 160 is too cold. 180--190--200 (depending on 180 or 190 thermostat) is just right at cruise or idle. 220 under heavy load is not a problem.
    5. 160 in the morning, 240 in the afternoon? Same amount of driving? I'd be considering a sticking thermostat.
    6. Got a photo or three showing how the HEI interferes with the PS and the intake manifold? I can't get a mental image of that.
     
  20. buickbill

    buickbill Well-Known Member

    I am unable to post pix on this site for unknown reason .they post everywhere else ! the timing is backing up when I start it ,but due to the clearance I cant advance it as the vac. adv. hits the p.s. belt I think I will remove it and see if it runs any cooler advanced . but like I said ,no more than 10 qts capacity . probabley even less . cant be big enough . might keep a v6 cool ! and yes I plan on 180 thermostat when I solve the other issues . but till then it goes up to 180+ pretty quik .
     

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