Please note this thread has been inactive for 90 days. For the best results, please start a new thread.
Results 1 to 10 of 10
  1. #1
    Lieutenant Junior Grade
    Join Date
    Sep 2009
    Location
    Erie, PA
    Posts
    1,120

    Default How to pour antifreeze in without flooding cylinders?

    It is a mercruiser 305CI. I drained the block, manifolds, and risers. Now I want to put antifreeze in but I have read if I do it wrong, water will flow into the cylinders thru the exhaust ports. What is the best way to do this?
    1988 Four Winns Sundowner 235, 5.7-4V 260HP OMC Cobra
    1977 Glastron V-184 Crestflite, 165HP Inline Six Mercruiser 1
    1978 Sea Ray SRV-195 Closed Bow, 165HP Inline Six Mercruiser 1, Awaiting Engine Transplant.

  2. #2
    Supreme Mariner roscoe's Avatar
    Join Date
    Oct 2002
    Location
    Medford WI
    Posts
    17,203

  3. #3
    Lieutenant Junior Grade
    Join Date
    Sep 2009
    Location
    Erie, PA
    Posts
    1,120

    Default Re: How to pour antifreeze in without flooding cylinders?

    I know how to read and have read this several times. How do I know HOW MUCH to fill thru the hoses? And again the engine will not be running to push any out that I may overfill.


    "If you are one of those that must use antifreeze instead of just draining, for whatever reason, you can fill the block and manifolds with a 50/50 water/antifreeze mix through the hoses to the manifolds and coolers and removing the thermostat and pouring antifreeze into the engine block. Many of the RV type antifreeze do not have corrosion inhibitors in them because they are meant to be used in the domestic water system."
    1988 Four Winns Sundowner 235, 5.7-4V 260HP OMC Cobra
    1977 Glastron V-184 Crestflite, 165HP Inline Six Mercruiser 1
    1978 Sea Ray SRV-195 Closed Bow, 165HP Inline Six Mercruiser 1, Awaiting Engine Transplant.

  4. #4
    Supreme Mariner
    Join Date
    Mar 2004
    Location
    On Barnegat Bay, NJ
    Posts
    15,742

    Default Re: How to pour antifreeze in without flooding cylinders?

    Add some AF with the plugs out. When the AF emerges from the drains, install the plugs and fill to overflow. The cooling system is seperate from the combustion system, so no AF will ever get into the combustion system, unless the block is cracked.

  5. #5
    Moderator Bond-o's Avatar
    Join Date
    Apr 2002
    Location
    The Mouth of the Chaumont River, Ny.
    Posts
    47,566

    Default Re: How to pour antifreeze in without flooding cylinders?

    but I have read if I do it wrong, water will flow into the cylinders thru the exhaust ports.
    Ayuh,... You read Wrong,... That can't happen...
    Any Grease is Better,..... Than No Grease at All.......

  6. #6
    Temporarily Suspended
    Join Date
    Dec 2004
    Location
    Peoria, IL
    Posts
    6,404

    Default Re: How to pour antifreeze in without flooding cylinders?

    Quote Originally Posted by Bond-o View Post
    Ayuh,... You read Wrong,... That can't happen...
    Ayuh, exactly.

  7. #7
    Lieutenant Junior Grade
    Join Date
    Sep 2009
    Location
    Erie, PA
    Posts
    1,120

    Default Re: How to pour antifreeze in without flooding cylinders?

    This is great to know. How about where it mentioned dieseling after shutoff how water could get in? How is that part possible?

    This part here:

    "13. Bring the rpm up to around 1500 rpm and start squirting fogging oil into the carb till the rpms drop and you are getting a lot of smoke out the exhaust. Then shut off the engine. If the engine diesels, restart it fog some more, make sure the idle is very low and shut it off again. You don't want water backed up into the cylinders from running backwards."
    1988 Four Winns Sundowner 235, 5.7-4V 260HP OMC Cobra
    1977 Glastron V-184 Crestflite, 165HP Inline Six Mercruiser 1
    1978 Sea Ray SRV-195 Closed Bow, 165HP Inline Six Mercruiser 1, Awaiting Engine Transplant.

  8. #8
    Moderator Bond-o's Avatar
    Join Date
    Apr 2002
    Location
    The Mouth of the Chaumont River, Ny.
    Posts
    47,566

    Default Re: How to pour antifreeze in without flooding cylinders?

    Ayuh,... Apples,+ Oranges....

    Pouring fluid into the cooling system allows it to flow with gravity....

    Reversion from dieseling causes the cylinders to Suck the fluid back up from it's dump point in the exhaust flow...
    Any Grease is Better,..... Than No Grease at All.......

  9. #9
    Lieutenant Junior Grade
    Join Date
    Sep 2009
    Location
    Erie, PA
    Posts
    1,120

    Default Re: How to pour antifreeze in without flooding cylinders?

    Good to know. Well I guess is it much easier than I thought.

    Thanks.
    1988 Four Winns Sundowner 235, 5.7-4V 260HP OMC Cobra
    1977 Glastron V-184 Crestflite, 165HP Inline Six Mercruiser 1
    1978 Sea Ray SRV-195 Closed Bow, 165HP Inline Six Mercruiser 1, Awaiting Engine Transplant.

  10. #10
    Banned
    Join Date
    Sep 2008
    Location
    Chart 12274 Maryland
    Posts
    4,635

    Default Re: How to pour antifreeze in without flooding cylinders?

    Quote Originally Posted by TilliamWe View Post
    Ayuh, exactly.
    Ayuh, x3

Similar Threads

  1. 89 Mecury 100 Cylinders Flooding
    By shoots7066 in forum Mercury & Mariner Outboards
    Replies: 3
    Last Post: June 29th, 2009, 08:25 AM
  2. what hoses do you pour the antifreeze in when winterizing a mercruiser 260?
    By weider1717 in forum Mercruiser I/O & Inboard Engines & Outdrives
    Replies: 8
    Last Post: October 23rd, 2008, 07:50 PM
  3. Antifreeze in cylinders
    By proline2550 in forum Mercruiser I/O & Inboard Engines & Outdrives
    Replies: 6
    Last Post: May 15th, 2006, 08:51 AM
  4. Antifreeze in cylinders posted last night
    By proline2550 in forum Mercruiser I/O & Inboard Engines & Outdrives
    Replies: 7
    Last Post: April 19th, 2006, 08:04 AM
  5. antifreeze in cylinders - MCM165
    By dsamuelson in forum Mercruiser I/O & Inboard Engines & Outdrives
    Replies: 4
    Last Post: April 7th, 2004, 09:48 PM
  1. iboats Forum Directory - Over 100,000 forum posts organized by topic