Freeze Plug Blew Out
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From: San Antonio, TX
A friend was driving the Miata last night and it started fish tailing on her on a highway exit ramp then the temperature started climbing fast so she shut it off and coasted it into a parking lot. I got it towed back last night and took a look this evening to find the freeze plug missing. I'm wondering if I installed it improperly or got the wrong size or is this a common thing (I would hope not)?
It was a 30mm plug for the front water neck. I used black gasket sealant on the inner edge and tapped it in with a flat tip screw driver and hammer keeping it even along the perimeter. The edge of the freeze plug sat flush with the edge of the hole. Is it supposed to be sunken in further?
Should I just replace it with another, get one of those adjustable ones, or buy a block off plate from Begi just up the road and be done with it?
Mine installed 2 months ago...

Photo from tonight of the aftermath...
It was a 30mm plug for the front water neck. I used black gasket sealant on the inner edge and tapped it in with a flat tip screw driver and hammer keeping it even along the perimeter. The edge of the freeze plug sat flush with the edge of the hole. Is it supposed to be sunken in further?
Should I just replace it with another, get one of those adjustable ones, or buy a block off plate from Begi just up the road and be done with it?
Mine installed 2 months ago...

Photo from tonight of the aftermath...
parts index says 1.18"
the 30mm plug I used crushed in quite a bit to fit. I used a socket to drive it in and had trouble removing [the socket] as I used one that was too large of a diameter.
the 30mm plug I used crushed in quite a bit to fit. I used a socket to drive it in and had trouble removing [the socket] as I used one that was too large of a diameter.
Thread Starter
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From: San Antonio, TX
I tried using a socket when installing mine but one side would always be popping out so I ended up using a screwdriver and hammer and just tapping it in evenly.
I lost one a couple years ago. Tried 2 from NAPA that were supposedly the right size, and they wouldn't go in properly. Got one from the stealership and it popped right in, nice and flush.
I ordered an OE mazda one.... Only made it 2 months huh? I drove mine in like any other freeze plug, did it dry. I had a 'near' overheat a week ago that resulted in my radiator exploding (3" crack in the top), so I'm thinking that since the plug survived that I'm surely ok.
Joined: Jun 2005
Posts: 19,338
Total Cats: 574
From: Fake Virginia
Install the next one with Indian Head Shellac.
http://www.permatex.com/products/aut...c_Compound.htm
http://www.permatex.com/products/aut...c_Compound.htm
A cover plate over the freeze plug is standard for any car we touch there. Not using a cover plate is asking for trouble - I've seen several cars blow that plug out.
Joined: Jun 2006
Posts: 29,085
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From: Republic of Dallas
Make one and send it to me with two bolts, and I need it by next weekend. I'm not ******* around, this is a serious order request, ******. Make me a paypal invoice.
I was riding along in a track car when it blew out the plug going up to turn 2 at infineon. The windshield was covered in 200+ degree water and generally was not a pleasant experience. A plate and, I think, a new plug solved the problem. A plate is a good investment.
Thread Starter
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From: San Antonio, TX
Cool, a friend who works on motors told me to use Permatex No.1 (the hard-setting sealant) instead of the No. 2 (soft-setting) that I used previously.
http://www.permatex.com/products/Aut..._1_Sealant.htm
http://www.permatex.com/products/Aut..._1_Sealant.htm
I used Ultra Grey and a plate.
had no idea these things were blowing out on people.
Permatex® Ultra Grey® Rigid High-Torque RTV Silicone Gasket Maker
OEM specified. Designed specially for high-torque and high vibration applications, like those common in import engines, this premium RTV gasket maker exceeds manufacturers' performance requirements. Noncorrosive and low-odor. Maximum vibration resistance, with outstanding resistance to oils, cooling and shop fluids. Guaranteed not to leak. Temperature range -65ºF to 500ºF (-54°C to 260°C) intermittent.
Suggested Applications: Valve covers, oil pans, intake manifold end seals, timing covers, water pumps, thermostat housings
OEM specified. Designed specially for high-torque and high vibration applications, like those common in import engines, this premium RTV gasket maker exceeds manufacturers' performance requirements. Noncorrosive and low-odor. Maximum vibration resistance, with outstanding resistance to oils, cooling and shop fluids. Guaranteed not to leak. Temperature range -65ºF to 500ºF (-54°C to 260°C) intermittent.
Suggested Applications: Valve covers, oil pans, intake manifold end seals, timing covers, water pumps, thermostat housings
had no idea these things were blowing out on people.








