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  • ~Chad~
    replied
    Or buy that 350 they have listed on here.

    Leave a comment:


  • Paul
    replied
    Originally posted by Brad-S View Post
    How did the mechanic diagnose a cracked block below the top of the pistons? That sounds like a shot in the dark. I agree with Beckman, I almost guarantee it's a head gasket. A little white smoke last year was probably it going south. After it sat all winter the antifreeze leaked into the cylinder which is why it wouldn't crank. When you finally got it started, the extra pressure from being hydro locked made the head gasket situation worse and now you have a milkshake.
    Change the oil and run it again. If the oil turns milky again you know you still have a problem. You should be able to pull the plugs and see which ones are clean, which would indicate which cylinders are getting water in them. You can also do a leak down test to see which side of the motor may have the bad gasket. Most likely as Beckman stated, between 2 cylinders. I've seen it many times.
    I have a 5.7 and also added an Edelbrock Intake and 4 Bbl Holley carb, it made a nice difference!
    This. And Beckmans thoughts.
    Worth a try to simply do a couple oil changes with cheap oil to absorb and flush out as much milkshake as possible and to see if the problem persists. If it comes back then it probably the gasket/s. If not could have been trom dumping the antifreeze down the wrong pipe.

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  • 205ccrCrownie
    replied
    I had a boat 25 years ago and left it uncovered during a downpour. The next week, I checked the oil and it was high and milky. I changed the oil and didn't have problems like this ever again.
    Maybe this is the case for you. It's a long-shot but worth a try. If you are not that lucky, i agree that it is probably head gasket.
    Joe

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  • Brad-S
    replied
    How did the mechanic diagnose a cracked block below the top of the pistons? That sounds like a shot in the dark. I agree with Beckman, I almost guarantee it's a head gasket. A little white smoke last year was probably it going south. After it sat all winter the antifreeze leaked into the cylinder which is why it wouldn't crank. When you finally got it started, the extra pressure from being hydro locked made the head gasket situation worse and now you have a milkshake.
    Change the oil and run it again. If the oil turns milky again you know you still have a problem. You should be able to pull the plugs and see which ones are clean, which would indicate which cylinders are getting water in them. You can also do a leak down test to see which side of the motor may have the bad gasket. Most likely as Beckman stated, between 2 cylinders. I've seen it many times.
    I have a 5.7 and also added an Edelbrock Intake and 4 Bbl Holley carb, it made a nice difference!

    Leave a comment:


  • Michael Beckman
    replied
    Well, here is my 2¢, I believe the issue is the Cylinder Head Gasket. The weakest points of the Cylinder Head Gasket is between the cylinders. The engine is definitely sucking water into the Crankcase and it is being agitated, hence the "milkshake". Before pulling the Engine, pull the Intake Manifold and Cylinder Heads for examination. Either way this is part of the repair process at some point. If it is just Head Gasket failure you can handle this repair in the privacy of your own garage as a DIY project. One or both of the Cylinder Heads might be warped causing the Head to leak at the web between Cylinders. Have the Cylinder Heads resurfaced and rebuild. If your 208LX is currently adorned with a 2Bbl carb. and you desire a little "pick-me-up", change your current setup with a new 4Bbl Intake Manifold and Carb. Good Luck.

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  • ~Joey~
    replied
    Interesting. I’d change the oil and fire it back up. If it continues maybe head gasket or crack? Good luck man

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  • Mark-P
    replied
    I winterize the same way but not through the allen bolts on top of the risers.

    For as long as i have had my boat the starboard riser on the first 20 min of running is way hotter than tthbprot and they do equalize. Not sure what causes that but have quit worrying about it.

    You may have hydrolocked it. I might just change oil again and watch it and see if it duplicates it without the winterization.

    Leave a comment:


  • Ksupaul
    replied
    Wow this is bad luck. I’m sorry your facing it. Come on gear heads, what are your thoughts? I haven’t knock on wood experienced anything like this so no help mechanically or replacement cost wise.

    Leave a comment:


  • sek-hunter
    started a topic Long Read/Advice Needed/Cracked Block?

    Long Read/Advice Needed/Cracked Block?

    So, this is kinda painful, and long. I'll try to get to the point.

    So it was a busy spring and we were late as always getting the boat on the water. Memorial weekend we decided to put it in the water for the first time. I always start the boat at the house on muffs before going to the lake the first time of the year. So I hooked the muffs up, turn the key, and get a loud 'click'. Check the battery, checks good. Buy a new battery anyway. Same result when I turn the key. Sounds like the starter is engaging but not turning.

    Pull the starter and bench test with old battery. Starter works. Take it to starter shop for confirmation. Starter checks out OK. He replaces the solenoid for good measure. Says they sometimes work intermittently. Replace starter. Hesitant to turn over, but finally does.

    So now the engine is cranking, but won't start. I determined that I may have flooded it, so I run to the parts store for some plugs. $70 later, I replace the plugs and BAM fires right up! But I notice a problem. I'm getting some whitish smoke out of the prop and starboard side exhaust port out back. Not as much water coming from starboard side. The exhaust riser on the starboard side is noticeably hotter to the touch than the port side. ???? I remember a faint smoke last fall around the dock coming from under swim platform. I'm thinking risers or manifold rotted or head gasket.

    Check the oil and sure enough, it is milky looking and way overfull.

    Rewind to last fall. The boat is a 2003 Crownline 208LX with the carbed 5.0 Mercruiser. I have owned it since 2012. I have always done my own maintenance on the boat from impellers, to oil changes, to outdrive fluid changes, to winterization.....

    This may be wrong, or incomplete, but here is how i winterize as far as freeze prevention. It has always worked. Drain water at 5 points. Reinstall blue plugs. Remove hoses from thermostat housing going to exhaust. Fill each side with RV antifreeze until it runs out the back. Remove thermostat housing. Fill with RV antifreeze until full.

    This year I was in a hurry and had trouble getting cooling hoses for the exhaust free. So I removed the Allen plugs from the top of the riser and filled the exhaust that way. MAYBE THAT WAS WRONG? DID THAT HYDROLOCK MY MOTOR?

    Also, I didn't fog the engine this year, but I rarely do?

    My boat is stored in my garage year round. It is insulated, but unheated. We live in KY and had a very mild winter. I cannot see how freezing would have been an issue.

    Take the boat to a fellow who specializes in inboard engines. He calls a few days later says I need a motor. Water is getting in the oil but not on top of the pistons. Must have a cracked block, but how.

    He says a reman Merc with new heads is $4,300 plus $1,700 labor to remove and replace. Does that sound about right?

    I have to chat with him some more..... Not sure what to make of this. The boat runs fine. Don't know what went wrong. What are your thoughts on diagnosis and the price for the new motor? I'm kinda in the dumps about the whole deal. It is too nice of a boat not to fix, but damn, I was not expecting this!
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