Coolant leak help

Small Block Mopar Engine

  1. Austin Schlegel

    Austin Schlegel New Member

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    Hi all,

    I am relatively new to the classic mopar scene and working on old cars in general. I just recently bought a 68 barracuda with a 318 (bored +0.010" over). The car had been sitting outside for an unkown amount of years. When I first got it I checked the oil dipstick and it looked fine, was dark brown and full. I managed to get the engine running and it sounded like it was running fine. I never ran the engine for more than roughly 5 mins.

    Recently I checked the oil and it was milky, so I drained it all out. I have taken off the heads thinking it was a blown head gasket but they looked fine. The intake manifold gaskets looked pretty rough though. Can that cause a coolant leak into the engine? I have not taken off anything but the heads, so it could be something else. Any advice?

    Also, is there anything I need to do after replacing the gaskets? Like flush the rad?

    Thanks in advance,
    Austin
     
  2. RedFish

    RedFish Well-Known Member

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    Yes, failed intake gasket can let coolant into oil.
     
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    • 69cudaownr

      69cudaownr FABO Gold Member FABO Gold Member

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      And if you pulled the heads then change those gaskets too. I would flush the rad if it was sitting for a period of time and replace with new coolant.
       
    • Murray

      Murray FABO Gold Member FABO Gold Member

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      Next time, pressure test the system to find the leak before tear down.
       
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      • 66fyssh

        66fyssh Don't Stop Believin' FABO Gold Member

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        I once saw slightly milky oil that was the result of not getting the engine warm enough. It was cold outside though and I only ran it a short time. I warmed it up real well and changed oil. No problem afterwards.

        But in your case it sounds like the intake gasket. And, sitting that long is never good.
         
      • cudamark

        cudamark FABO Gold Member FABO Gold Member

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        I would bet on a leaking timing cover.
         
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        • Austin Schlegel

          Austin Schlegel New Member

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          I'll be sure to test the compression next time. So I have the heads off, should I remove anything else to check? Not sure how easy the timing cover will be
           
        • 66fyssh

          66fyssh Don't Stop Believin' FABO Gold Member

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          That's a loaded question, lol.

          Since you're not completely sure the problem was the intake gaskets it would be good to pull the water pump and timing cover. But yeah, you could run into trouble with seized bolts. Then there's the thing with the oil pan. I always like installing timing cover first. Then oil pan. It never stops, lol.

          Whatever you decide, take your time. And ask here if you have any questions.
           
        • Rapid Robert

          Rapid Robert Well-Known Member

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          You can buy a fitting with 1/8 NPT threads on one end and a schrader (tire psi) threads on the other end for less than $3 at O'reillys. take out the coolant sensor sender & replace it with this fitting then pump it up with your air hose to ~10 PSI or so & see if it holds pressure. as you know leaks can be external or internal. Add air in very short blips cuz it ain't like airing up a tire where you go minuites at a time & you can reach a critical pressure in no time & blow a hose out.

          SAM_0837.JPG
           
        • furrystump

          furrystump Well-Known Member

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          Pictures of the deck surface and gaskets, pictures of the valley. You would not believe what the people here will see in a picture that a newer person might miss. Plus we like pictures. You can just pull the water pump off the timing cover and it might give you an idea of how rusty the rest of the system is. SUPER rusty, you might lean towards the cover leaking. Water that hasn’t evaporated out of the oil. can make you think you have an issue when you might not. When you put the heads back on, torque the heads down in sequence and let it sit overnight. Back each off a 1/4 turn in sequence and retorque. They will turn more. Like stated above, if something feels different or just weird ask.
           
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