Square Plug in Heads....
Thread Starter
Le Mans Master
Joined: Jun 2001
Posts: 6,694
Likes: 3
From: Less Talk, More WOT | Houston TX
Square Plug in Heads....
I was going through my pile of leftover stuff after my rebuild, and just now realized I'm missing the temp sensor that runs the boost fan on my '89. There is a plug with a square hole in the block where the sensor goes... How the hell can I get this thing out? I cant find anyone who has square socket bits and my attempts to get it out with a piece of bar stock on a pair of pliers isn't working either. 
Thread Starter
Le Mans Master
Joined: Jun 2001
Posts: 6,694
Likes: 3
From: Less Talk, More WOT | Houston TX
Le Mans Master
Joined: Apr 2001
Posts: 7,410
Likes: 252
From: Little Elm TX
You might want to make sure you don't have an "extra" hole over there as I did. I ended up re-wiring my sensor as I found it impossible to get the plug out and I wasn't about to take the heads back off the car.
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
A lot of guys have mentioned the trouble getting that plug out.
You might buy a short 1/2" extension and grind if down to a very tight fit into that square hole; you do NOT want it to slip and bugger the thing. Try spraying it with PB Blaster; not sure if it will work here but won't hurt.
If that fails have a shop do it, maybe using some heat on it.
You might buy a short 1/2" extension and grind if down to a very tight fit into that square hole; you do NOT want it to slip and bugger the thing. Try spraying it with PB Blaster; not sure if it will work here but won't hurt.
If that fails have a shop do it, maybe using some heat on it.
Thread Starter
Le Mans Master
Joined: Jun 2001
Posts: 6,694
Likes: 3
From: Less Talk, More WOT | Houston TX
I had the same issue when the heads for my car where returned. Apparently F-bodies had the sensor on the OTHER side and mine were switched out! You might want to make sure you don't have an "extra" hole over there as I did. I ended up re-wiring my sensor as I found it impossible to get the plug out and I wasn't about to take the heads back off the car.
You might want to make sure you don't have an "extra" hole over there as I did. I ended up re-wiring my sensor as I found it impossible to get the plug out and I wasn't about to take the heads back off the car.
Team Owner
Joined: Dec 2000
Posts: 21,094
Likes: 282
From: Phila., PA burbs
Its a 5/16" square hole. Yoo could grind an extension to fit or you try what I did. I got a section of 5/16" square rod from home depot and cut a sectiondown to make a bit. Then you just have to find a socket that fits it. The rod did have a tendency to want to twist, but I got the plug out eventually. You might be able to harden the rod a bit by heating it.
Le Mans Master
Joined: Jun 2006
Posts: 5,642
Likes: 5
From: One day you're a Comet...the next day you're dust... Arkansas
I've heard they are a bitch to get out. Put some blaster on it. When you get the sensor for it, it's a 22mm socket to install!
When I changed my sensor I ran out about 3 quarts of coolant so be ready to catch it. I think it's actually a metric size close to 5/16" FWIW.
When I changed my sensor I ran out about 3 quarts of coolant so be ready to catch it. I think it's actually a metric size close to 5/16" FWIW.
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