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Draining Mercruiser 228 cooling system

J

jackman

Contributing Member
Are the petcocks on cylinder block fragile? I tried turning the taps but they are very tight and I'm afraid of using too much pressure and snapping something. Likewise the various drain plugs won't move. I've given all a good dose of WD40 and could use a long torque wrench with socket on the drain plugs but thought I'd seek advice first. Thanks in advance for any info.
 
Those are all brass 1/8" NPT hex plugs, right?
Normally they enscrew with little effort.
The block drains typically have a built in small drain valve with a tiny valve handle that you turn CCW to open.
Sounds like they were put in too tight for some reason.
Regardless, if its RWC, they have to come out for winterizing.

Rod

Rod
 
When you get the petcock plugs out probe the openings to flush out the rust and scale. I use a 6" length of heavy solder or aluminum wire and bend the probe end a little to be able to twist it around inside the hole until there is a strong flow of water exiting the opening. Reinstall the petcock plugs after coating the threads w/a dab of neversieze or heavy grease and turn them untill they are finger snug. If they leak a little water the rust in the block will soon stop the leak.
 
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You may want to warm the engine up before trying to remove these. Heat can be your friend on things like this.

FYI; the automotive version of Never-Seez or Anti-seize contains conductive materials. Engine bolts, etc, it's a great product!
But these should NOT be used a wet Marine environment.
Instead, substitute a thread sealant, or the Marine version Anti-seize.

.
 
RicardoMarine said:
You may want to warm the engine up before trying to remove these. Heat can be your friend on things like this.

FYI; the automotive version of Never-Seez or Anti-seize contains conductive materials. Engine bolts, etc, it's a great product!
But these should NOT be used a wet Marine environment.
Instead, substitute a thread sealant, or the Marine version Anti-seize.

.
Click to expand...

Rick,
I have been using the silver never seize by permatex on the spark plug threads for longer than I can remember, should I quit doing this? I am a fresh water trailer sailor.
Thanks.
 
gl115 said:
Rick,
I have been using the silver never seize by permatex on the spark plug threads for longer than I can remember, should I quit doing this? I am a fresh water trailer sailor.
Thanks.
Click to expand...

Ayuh,.... You'll be just Fine....

Though I admit, I've been movin' to Merc Perfect-Seal...

I've been slatherin' things I've taken apart with Never-Seize most all my life...
Especially if I thought I might wanta take it apart Again someday...
 
I'm going to keep using it. Below is the label. If it's good enough for my brothers in arms standing guard against terrorists it's good enough for me. Former US Army Spec. 5th Class, HAWK Radar and Missile System Repairman, Aug. 1969 - Feb. 1972. Proud to be an American! Support our troops.

Permatex® Anti-Seize Lubricant
A highly refined blend of aluminum, copper and graphite lubricants. Use during assembly to prevent galling, corrosion and seizing and to assure easier disassembly. Temperature range: -60°F to 1600°F (-51°Cto 871°C). Salt, corrosion and moisture resistant –ideal for marine use. Non-aerosol version meets Mil Spec #907E. Aerosol - Level 3*
 
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bondo said:
Ayuh,.... You'll be just Fine....

1.... Though I admit, I've been movin' to Merc Perfect-Seal...

2.... I've been slatherin' things I've taken apart with Never-Seize most all my life...
Especially if I thought I might wanta take it apart Again someday...
Click to expand...
1.... I too like Perfect Seal.... pretty hard to beat it.

2..... Bill, for anything that is not subjected to sea water, sure..... it works well. I been using Never-Seez for over 45 years.
In fact, I have one can of Never-Seez that is probably older than many members here.
But give this a try on your salt water stern drive nuts/bolts..... you may be playing a different tune in the not so distant future.


gl115 said:
Rick,
I have been using the silver never seize by permatex on the spark plug threads for longer than I can remember, should I quit doing this? I am a fresh water trailer sailor.
Thanks.
Click to expand...
NO.... don't quit using it for this application..... works great!
Your spark plug threads are not going to be subject to salt water.
(See above response to Bill)

guyjg said:
Permatex® Anti-Seize Lubricant
A highly refined blend of aluminum, copper and graphite lubricants. Use during assembly to prevent galling, corrosion and seizing and to assure easier disassembly. Temperature range: -60°F to 1600°F (-51°Cto 871°C). Salt, corrosion and moisture resistant –ideal for marine use. Non-aerosol version meets Mil Spec #907E. Aerosol - Level 3*
Click to expand...
If you are reading this from a can of Never-Seez that contains aluminum and/or copper, I'm quite surprised.
It's these two elements that offer superior anti-seizing ability.
However, these same two elements will give you grief when salt water gets to it for any duration.

I love these products.... don't get me wrong.
I simply pick and choose them for the appropriate application!
Do this, and you'll be fine. :)

.
 
First , sorry Jackman, did not mean to hijack this thread.
second, thanks for all the responses, it has always been silver for low temp and copper for high temp.
That's what makes this forum great I always learn something.
 
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