Block coolant drain plug....
Thread Starter
Joined: Dec 2001
Posts: 9,946
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From: Chicagoland
Car: 1989 IROC-Z. Original owner
Engine: LB9. Dual Cats. Big Cam
Transmission: World Class T-5
Axle/Gears: BW 3.45
Block coolant drain plug....
It's located on the block forward of the oil filter. Up until recently, I didn't even know it existed.
About 3 or 4 years ago, I walk into my garage and see a gallon or two of coolant under my '85. I freaked out!!
It turns out the drain plug had loosened. How that happened, I have no idea. I tightened it, topped off the coolant and that was that.
Until now, I noticed a couple drops of green on the garage floor. It turns out it's the same plug. I tightened it but appears to be weeping slightly. What gives?
Has anyone had any trouble with this thing? Why would it loosen and what did you do about it?
About 3 or 4 years ago, I walk into my garage and see a gallon or two of coolant under my '85. I freaked out!!
It turns out the drain plug had loosened. How that happened, I have no idea. I tightened it, topped off the coolant and that was that.
Until now, I noticed a couple drops of green on the garage floor. It turns out it's the same plug. I tightened it but appears to be weeping slightly. What gives?
Has anyone had any trouble with this thing? Why would it loosen and what did you do about it?
Last edited by chazman; Nov 11, 2016 at 12:19 AM.
Joined: Sep 2005
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Re: Block coolant drain plug....
Probably not "loosening". More likely, corroding.
Replace it. ¼" pipe. Get a brass one at Home Depot or something. Make sure it's the kind with the LARGE hex head; not the small square head, not an Allen.
Replace it. ¼" pipe. Get a brass one at Home Depot or something. Make sure it's the kind with the LARGE hex head; not the small square head, not an Allen.
Thread Starter
Joined: Dec 2001
Posts: 9,946
Likes: 644
From: Chicagoland
Car: 1989 IROC-Z. Original owner
Engine: LB9. Dual Cats. Big Cam
Transmission: World Class T-5
Axle/Gears: BW 3.45
Re: Block coolant drain plug....
Any sources for a factory replacement drain plug? I haven't been able to find one.
Thread Starter
Joined: Dec 2001
Posts: 9,946
Likes: 644
From: Chicagoland
Car: 1989 IROC-Z. Original owner
Engine: LB9. Dual Cats. Big Cam
Transmission: World Class T-5
Axle/Gears: BW 3.45
Joined: Oct 2001
Posts: 12,228
Likes: 1,156
From: Il
Car: 1989-92 FORMULA350 305 92 Hawkclone
Engine: 4++,350 & 305 CIs
Transmission: 700R4 4800 vig 18th700R4 t56 ZF6 T5
Axle/Gears: 3.70 9"ford alum chunk,dana44,9bolt
Re: Block coolant drain plug....
IIRC, its about 1/2 long total
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Re: Block coolant drain plug....
If You Can't Find One In Home Depot,They Have A Factory One Here But The Shipping Is Twice The Cost Of the Plug. 
http://www.ebay.com/itm/1-4-NPT-Engine-block-Drain-Plug-SBC-BBC-350-396-427-454-V8-Auto-Farm-PP745-2/301125956504?_trksid=p2045573.c100033.m2042&_trkparms=aid%3D111001%26algo%3DREC.SEED%26ao%3D1%26asc%3D38530%26meid%3D3f4810eb3f5445dbac0013247c52e5bb%26pid%3D100033%26rk%3D1%26rkt%3D3%26sd%3D301125956504
http://www.ebay.com/itm/1-4-NPT-Engine-block-Drain-Plug-SBC-BBC-350-396-427-454-V8-Auto-Farm-PP745-2/301125956504?_trksid=p2045573.c100033.m2042&_trkparms=aid%3D111001%26algo%3DREC.SEED%26ao%3D1%26asc%3D38530%26meid%3D3f4810eb3f5445dbac0013247c52e5bb%26pid%3D100033%26rk%3D1%26rkt%3D3%26sd%3D301125956504
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Thread Starter
Joined: Dec 2001
Posts: 9,946
Likes: 644
From: Chicagoland
Car: 1989 IROC-Z. Original owner
Engine: LB9. Dual Cats. Big Cam
Transmission: World Class T-5
Axle/Gears: BW 3.45
Re: Block coolant drain plug....
If You Can't Find One In Home Depot,They Have A Factory One Here But The Shipping Is Twice The Cost Of the Plug.
http://www.ebay.com/itm/1-4-NPT-Engi...3D301125956504
http://www.ebay.com/itm/1-4-NPT-Engi...3D301125956504
Freakin' awesome! Thanks!