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Conference unifix::sailing

Title:SAILING
Notice:Please read Note 2.* before participating in this conference
Moderator:UNIFIX::BERENS
Created:Wed Jul 01 1992
Last Modified:Mon Jun 02 1997
Last Successful Update:Fri Jun 06 1997
Number of topics:2299
Total number of notes:20724

1398.0. "Freezeout plug repairs" by VLNVAX::FRENIERE () Tue Nov 21 1989 11:01

    In order to keep afloat this winter, I'm in a pratnership
    with a friend who has a Lyman 19 ft inboard bass boat. We
    are going to commision it in January after working over the
    bottom & planking. Also going to install a freshwater heat
    exchanger for the engine.
    
    The engine is just about a duplicate of my Gray in my sailboat.
    It looks about 40 or so horse power. It has a freeze out plug that
    leaks. My guess is that the best bet is to sand down the cast iron
    around the plug and epoxy over it.
    
    So Questions;
    
    If best bet is to pop it out & replace, what is the procedure?
    
    If best bet is to cover over with epoxy after cleaning the surrounding
    casting, what is the best epoxy to use.
    
    Although these are called out freeze out plugs, it is my understanding
    that they really are required to enable the blocks to be cast.
    Any comment ?
    Don

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1398.1Fun job.TARKIN::HAYSWhen the Gales of November come early .. Phil Hays LTN1-1/G08Tue Nov 21 1989 11:3317
RE:.0 by VLNVAX::FRENIERE

> a freeze out plug that leaks. 
> So Questions; If best bet is to pop it out & replace, what is the procedure?

Your best bet is to remove it and replace it with a rubber one.  If it is easy 
to work on,  and the plug that leaks is rusted through,  you might want to 
replace all of them.  If one is gone,  the rest may be close behind.  

To remove it, punch through the most rusted part of the center with an old 
screwdriver and try to pry it out.  If that doesn't do it,  use a broken 
hacksaw blade to cut through the rim and a punch to loosen.  The rubber freeze
plugs push in and tighten with a bolt.


Phil

1398.2Generalities about "freeze" or "core" plugsULTRA::BURGESSTue Nov 21 1989 11:4730
re                      <<< Note 1398.0 by VLNVAX::FRENIERE >>>
>                          -< Freezeout plug repairs >-

	I don't know the specific engine, but here are a couple of 
generalities:

	"Freeze plugs"  doesn't mean that they will absolutely protect 
the engine from freeze/ice damage.  As you say, they are plugs that 
fill holes which (in most cases) are necessary for the casting process 
to be practical.

	If this is a "general application" block (i.e. also used in 
cars. trucks, busses, wherever) it is likely to have standard plugs,
typical sizes are 1 inch, 1 1/8 inch, etc.  They are fairly easy to 
remove with a punch or chisel (or even a screwdriver) and even easier 
to replace, using a socket as a driver.  Replacements should be 
available from any auto parts store, but make sure to get brass 
"marine" plugs.

	At a guess the one that is leaking is probably steel and has
rusted, if this is the case then mucking around with epoxy won't fix
the underlying problem. 

	Another option is to replace it with a 115 Volt block heater,
these are ~$20, I mention this because you seem interested in winter
use. 

	Reg


1398.3Comments on Freeze plugsGIAMEM::T_MOORETue Nov 21 1989 12:1324
    Comment:  Do not fiberglass/epoxy over, at some point in time the
              epoxy/fiberglass will lose it bond (due to oxidation,
              ect).  I have worked on an engine that this was done,
              very messy to clean up and do right.
    
    Comment:  Replace is simple and easy.  If you experience difficulty
              removing use a "dent puller" (it's a sheet metal tool).
              Does a great job, if you need one I have one.  They can
              also be purchased at Sears, Kmart ect at the auto dept.
    
    Comment:  Most freeze plug are standard size (I bought a pocket
              full from a local auto parts store for a 1955 Jag).
    
    Comment:  To my understanding (of older auto's) they were used when
              antifreeze was not the quality of what it was today...
              IE they (the freeze plug) was to pop before the block
              split.
    
    Cheers,
    
    Tom
    
    

1398.4brass plugs?VLNVAX::FRENIEREMon Nov 27 1989 09:5219
    Talk about timleyness..
    
    My son had a freezeout plug pop on his Ford 6 cyl. It was under the
    manifold and difficult to get at. The auto parts place sold him
    a rubber plug of the type mentioned in .1. HOwever, they told him
    that this should not be depended upon beyond 6 months .
    
    John had a Chilton's manual. It had little to say other than to use a
    driver close to the diameter of the plug to drive it in. It also 
    said to use a "sealer" on the plug. There was no mention of the type
    of sealer. Guess I'll use Permatex when I do it as this is one that
    withstands heat & acids & water, etc.
    
    The engine I'm working on is another Gray of about 65 HP. The freeze
    plugs are of steel. The idea of brass plugs is interesting. I'll
    look for their availability.
    
    Don

1398.5CORE Plugs, not "freeze" plugsBIZNIS::CADMUSMon Dec 04 1989 15:5949
    
    
    Core plugs. Not "freezeplugs" is the proper term.  When a complex
    hollow casting like an engine block is made, holes are left for the
    sand core to attach to the main mold. THese attachment points for the
     casting core result in holes in the exterior of the casting and they
    are used to pour out ther sand from the core after the mold is cast.
    
     They are cleaned up with maching and a metal "plug " usua;l;y of steel
    or brass is used to plug the hole.
    
    BTW- the preious comment about anti-freeze not being the wuality og
    today's  stems from the days when Methanol was used as  a cheap
    substitute for ethylene glycol. It used to evaporate. leave yoyu with
    water, and the engine would freeze- the sore plugs, being weaker than
    the cast iron would pop out first, therefore, the commomn
    misunderstanding of their purpose. I have seen a lot of engines with
    the "freeze plugs popped out and a cracked block as well- I also
    have seen a lot of cracked blocks with the core plugs intact.
    
    
     Any good auto parts store should have the  BRASS plugs in the size you
    need. DO not use steel plugs or the rubber plugs with the steel bolts!
    
    The core plugs are dished and once the block is cleansed out- you
    should see that the block has a lip tha acts as a stop ( not as a seal)
    for the plug.  Liberlly apply Permatex to the lip, insert the plug with
    the Dish out, and flatten the "dish"- thus expanding the plug and
    sealing it.
    
     In some of the newer engines , the pkugs are cupped, and are inserted
     with the lip out- this is the case where a big socket that just fits
    inside the  plug is used as a driver- again- liberal use of permatex as
    a sealer and a lubricant is in order. With the cupped plugs, there is
    no lip inside the block to act as a stop- so only insert the plug until
    it is inside the block  and the lip is recessed about 1/8" all around.
    IF you push this type of plug in too far- it will be inside the block
    and if it's brass will give you untold grief with restricted water flow
    until you pull the head(s) and extract it through one of the water
    passages.
    
     There is a recent conference in AITG::Mechanics_II that deaks with
    Core plug removal and installation.
    
     my 2�
    
     Dick