J-B Weld
Team Owner
Joined: Feb 2006
Posts: 23,198
Likes: 117
From: San Antonio Texas
I've always had good luck with it as long as you rough up your fix area to give it something to get a good bite on. It's either a love it or hate it product. I'm in the 'love it' camp!
Pro
Joined: Oct 2012
Posts: 672
Likes: 2
From: Cheltenham, England
Used it for years,cant fault it, I've done everything from casting repairs to fixing leaking fuel tanks on motorcycles, provided surface prep is done right and you follow the recommended ratios you cant go wrong! and the best bit is the repair just keeps getting stronger as time goes on!
Last edited by ricasso; Feb 20, 2015 at 05:51 PM.
Drifting
Joined: Oct 2001
Posts: 1,770
Likes: 33
From: Cohasset MN
2017 Corvette of the Year Finalist
2016 C1 of Year Finalist
I used it many years ago on my '61 aluminum radiator that had a small leak at the top. It is still OK.
I noticed that JB weld now comes in some other forms, including one that you don't have to mix together. I tend to believe that the original product still is the strongest.
I noticed that JB weld now comes in some other forms, including one that you don't have to mix together. I tend to believe that the original product still is the strongest.
Race Director
Joined: Jan 2007
Posts: 14,948
Likes: 3,351
From: NYC NY
My friend used it to save a 502 block. There was a crack at corner of the block that went slightly into the oil filter sealing pad. He used the JB to repair the oil filter sealing area and it worked. No leaks on a block that was on it's way to the scrap yard.
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
The outer ring of my harmonic balancer walked into my timing chain cover and made a hole in it. I didn't want to take the oil pan off to replace the timing chain cover so I put J-B Weld on the hole and drove it for 10 years before doing the fix the correct way.
10 year old J-B Weld repair:
10 year old J-B Weld repair:
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Le Mans Master
Joined: Oct 2004
Posts: 6,314
Likes: 508
From: South-central Missouri
I've used it for 25 years to fix cracks and leaks on a variety of things from cars to lawnmowers, "glass bedding" custom rifles and rifle scopes...on and on and on... Really great stuff, short of welding/soldering!
Race Director
Joined: Aug 2000
Posts: 11,470
Likes: 764
great stuff! I've used J-B weld for years. I brought my 85's door panels back from the dead with this stuff, some .016 aluminum, and 1/8" pop-rivets. J-B works great with secondary bracing and support, especially on plastic interior pieces.
I've repaired, missing and broken tabs on plastic bezels by using J-B with aluminum screening as reinforcing material.
I've repaired, missing and broken tabs on plastic bezels by using J-B with aluminum screening as reinforcing material.
Thread Starter
Racer
Joined: Dec 2014
Posts: 402
Likes: 44
From: Pittsburgh PA
great stuff! I've used J-B weld for years. I brought my 85's door panels back from the dead with this stuff, some .016 aluminum, and 1/8" pop-rivets. J-B works great with secondary bracing and support, especially on plastic interior pieces.
I've repaired, missing and broken tabs on plastic bezels by using J-B with aluminum screening as reinforcing material.
I've repaired, missing and broken tabs on plastic bezels by using J-B with aluminum screening as reinforcing material.
Melting Slicks
Joined: Jun 1999
Posts: 2,931
Likes: 127
From: Ashland Alabama
Ive used it a bit 
I glued the bottom of the motor on a Suzuki 185 ts dirtbike where the previous owner didn't set the foot brake stop and hit a stump and cracked the motor case. Glued it at 300 miles and was still doing fine at 12,000 miles when the bike gave up the ghost.
I glued the corner of the block in my suburban where the outside starter bolt goes. Broke off around 110,000 miles. Still holding starters at 625,000 miles.
I glued a piston mounting pin socket on a front end loader tractor. Still works fine.
Ive glued about 20 radiators with it I imagine. The metal ones did fine and still are in service. The plastic sided ones didn't take the to the weld so they were a no go.
Ive glued maybe 4 manual transmissions that had cracked cases. All did fine.
Ive glued about 3 automatic transmission cases best I remember. Did fine.
I glued the transmission lines on my bmw when I mangled them changing the power steering pump. No real risk on that one since I was putting a manual trans in it the following month but it never leaked till I did the swap so worked great.
The list goes on and on. Great stuff if used right.
I glued the bottom of the motor on a Suzuki 185 ts dirtbike where the previous owner didn't set the foot brake stop and hit a stump and cracked the motor case. Glued it at 300 miles and was still doing fine at 12,000 miles when the bike gave up the ghost.
I glued the corner of the block in my suburban where the outside starter bolt goes. Broke off around 110,000 miles. Still holding starters at 625,000 miles.
I glued a piston mounting pin socket on a front end loader tractor. Still works fine.
Ive glued about 20 radiators with it I imagine. The metal ones did fine and still are in service. The plastic sided ones didn't take the to the weld so they were a no go.
Ive glued maybe 4 manual transmissions that had cracked cases. All did fine.
Ive glued about 3 automatic transmission cases best I remember. Did fine.
I glued the transmission lines on my bmw when I mangled them changing the power steering pump. No real risk on that one since I was putting a manual trans in it the following month but it never leaked till I did the swap so worked great.
The list goes on and on. Great stuff if used right.
Race Director
Joined: Feb 2002
Posts: 11,616
Likes: 1,055
From: Compound in the Grove, Ga.
2026 Corvette of the Year Finalist - Unmodified
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St. Jude Donor '16
Use a bit of cut stranded fiberglass with it and its even stronger.
Burning Brakes
Joined: Nov 2014
Posts: 936
Likes: 51
From: Post Falls ID
Countless repairs with it.
Boat motor cracked block. Someone drilled into the water jacket. I took a PK screw, globbed it with JB Weld, screwed it in there and ran that motor for two more years till I upgraded.
Another boat motor cracked exhaust riser. ground out a vee as if I were welding it, put the JB in there and when it dried, ground it smooth and painted it the stock OMC color. Can't even find the repair now, and it's been at least 10 years.
Just a couple examples...
It just plain works.
Boat motor cracked block. Someone drilled into the water jacket. I took a PK screw, globbed it with JB Weld, screwed it in there and ran that motor for two more years till I upgraded.
Another boat motor cracked exhaust riser. ground out a vee as if I were welding it, put the JB in there and when it dried, ground it smooth and painted it the stock OMC color. Can't even find the repair now, and it's been at least 10 years.
Just a couple examples...
It just plain works.
Instructor
Joined: Oct 2014
Posts: 142
Likes: 2
From: St. Joseph MO
I would love to hear more about this process. I've been working different scenarios through my mind and if this worked well I'd love to give it a try. A few details or things of particular concern would be greatly appreciated. Thank you in advance...
Pro
Joined: May 2012
Posts: 520
Likes: 9
I installed a new fuel pump in my tank but had to make joints as the wiring was slightly different, I will be removing it this spring and using JB to weld the joints together ( helps me turn that key with out worrying lol)
Burning Brakes
Joined: Nov 2014
Posts: 936
Likes: 51
From: Post Falls ID
I remember another one. I repaired the fuel line going to the throttle body injection in my old '90 Chevy work truck. Seems there was a chafe... So I wrapped with with aluminum, but before the wrap I JB'ed the repair area. The applied the wrap, with another layer of JB over the cured part. Put tyraps around the whole thing to keep some spiral-wind in place. It's been there several years (I'd forgotten about it).
I did buy a fire extinguisher and mounted it in the truck after doing that. But now it's been there so long, I have no reason to believe it'll be any more vulnerable than the new line I ordered, received, and was too lazy to install.
I did buy a fire extinguisher and mounted it in the truck after doing that. But now it's been there so long, I have no reason to believe it'll be any more vulnerable than the new line I ordered, received, and was too lazy to install.