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Broken Spark Plug amp I canbt get it out

H

hmeislin

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"Mercruiser 7.4 MPI IO, boat w

"Mercruiser 7.4 MPI IO, boat was in salt water for a long time, though on a lift when not in use. While chagning plugs, one broke off and I can't get the spark plug socket in far enough to get a grip on the plug. The base of the plug and surrounging opening are corroded. HELP?!?!"
 
Soak the area with WD-40 over

Soak the area with WD-40 over night. WD-40 has amazing penetrating abiity. Perhaps this experience will demonstrate the value of using anti-sieze on the threads of spark plugs when installing them.
 
there are better penetrating o

there are better penetrating oils than wd 40 but you get the idea. soak the area. Use a 6 point socket if you are not doing so already. You may need to dedicate a few sockets to the task. You may need to grind the sidewalls of the socket thinner so it reaches in deep and seats around the socket. Use a touch of anti sieze compound on the threads of the new plugs when installing. I've used anti sieze on plugs for 15 years and swear by it.
 
Tried everything suggested. Th

Tried everything suggested. The plug is getting rounded and I can't get torque. What now??
Will an easy out work?
 
"Harvey:

You have to disso

"Harvey:

You have to dissolve the corrosion first. Vacuum the metal particles and dirt from the plug area and use a tiny thin slotted (flat for you BYMs) screwdriver to scrape around the plug and vacuum it again. SEVERAL applications of PB BLASTER over SEVERAL days with additional scrapings and vacuumings may save your wallet.

When turning the plug; lefty loosey or CCW to remove plugs. Apply alot of downward force with a 1/2" drive socket, 12" or longer extension and 1/2" breaker bar. If you feel a slight budge and not a slipping socket, STOP and soak it again and repeat several times daily until it is free. Then chase the threads with a thread cleaning tool, not a tap, covered in grease to catch the crud.

Don't make it worse if it won't budge--take it to an automotive machine shop.

Guy"
 
Acetylene torch. Heat the hea

Acetylene torch. Heat the head in the area around the plug and out it will come.

Jeff
 
"Harvey: When all is done, us

"Harvey: When all is done, use Mercruiser's protective engine and OD spray since you are in salt water."
 
"The torch (aka smoke wren

"The torch (aka smoke wrench) is a great technique but for the sake of safety, I would NOT advise unless you are as comfortable with a flame as using a ball point pen. Time to pay the man."
 
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