Ok to use heat on leaf spring?
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Joined: Jul 2023
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Ok to use heat on leaf spring?
The ride adjustment bolt on the front driver side is completely seized, try as I might I can't get it to turn either direction. At first I was just planning to lower the car on stock bolts but after seeing them it looks like the pads are starting to deteriorate so I was going to replace them.
Short of taking the whole spring out (and beating it with a hammer out of frustration at this point!) can I use a torch on the spring around the bolt to try and free it up?
Short of taking the whole spring out (and beating it with a hammer out of frustration at this point!) can I use a torch on the spring around the bolt to try and free it up?
Race Director
Joined: Aug 1999
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From: SE Pennsylvania
St. Jude Donor '03 thru '26
Oldtimer
If you want to cut the bolt out fine, but you stand a good chance of setting the car on fire if you start using a acetylene torch on the spring, it compressed fiber and it will BURN !
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Im not even sure I can cut it out because there will still be a piece inside the leaf...I suppose that would mean drilling it out and re-tapping the hole. I think my best course is taking the whole leaf out and trying to put the bolt in a vice.
Le Mans Master
Joined: Jan 2001
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From: Hilton NY
I heated the head of the bolt some (from the side) but not too much with a Bernzomatic torch while keeping the heat away from the spring with some scrap sheet aluminum, it took a few tries so it wouldn't get too hot. There's a steel bushing molded into the spring (it's what the bolt is rusted in) that started turning with the bolt when the bushing to spring molding bond broke from the heat. When the bushing turns with the bolt both can be tapped out by hitting the bolt head. Once the bushing was out it was placed in a vice and heated enough (red hot) to remove the rusted in bolt. After the threads were cleaned up the cooled bushing was degreased and epoxied back into the degreased spring. Since the pocket for the bushing doesn't go all the way through the spring the epoxy held fine, only the smaller bolt hole goes all the way through.
Race Director
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From: SE Pennsylvania
St. Jude Donor '03 thru '26
Oldtimer
OK, I can't see it and only you could know, But how about a Sawzall, and I'm just guessing that you could use it instead of a torch. You can get a longer saw blade for metal, but they tend to get kind of of squirrely the longer the blade, any chance of a picture. I'm kind of a torch-phobic even though I am a welder..But anything involving a flame and a Corvette can lead to a real bad experience !
Le Mans Master
Joined: Jan 2001
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From: Hilton NY
A Sawsall won't heat up the bolt/bushing assembly so that it will rotate in the spring and then be tapped out, nothing needs to be cut. The bushing looks like a short steel shaft about an inch in diameter and slightly thinner than the spring with a tapped hole in it. If you don't feel comfortable using a torch with the spring in the car then remove the spring and as mentioned above try using a vice to hold the bolt. The drivers side adjusting bolt on my car was rusted so bad no amount of penetrating oil could free it, once it was heated red hot after it was removed from the spring it could be unscrewed from the bushing. If somehow you get the bolt to turn with the bushing then the bushing is loose in the spring and can be tapped out.
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I heated the head of the bolt some (from the side) but not too much with a Bernzomatic torch while keeping the heat away from the spring with some scrap sheet aluminum, it took a few tries so it wouldn't get too hot. There's a steel bushing molded into the spring (it's what the bolt is rusted in) that started turning with the bolt when the bushing to spring molding bond broke from the heat. When the bushing turns with the bolt both can be tapped out by hitting the bolt head. Once the bushing was out it was placed in a vice and heated enough (red hot) to remove the rusted in bolt. After the threads were cleaned up the cooled bushing was degreased and epoxied back into the degreased spring. Since the pocket for the bushing doesn't go all the way through the spring the epoxy held fine, only the smaller bolt hole goes all the way through.
Safety Car
Joined: Aug 2011
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From: Portland OR
The stock bolts are pretty soft. Mine were actually bent. I soaked them with Kroil (I believe there are better penetrants now) and was finally able to break them free.
Had to double nut the top because the hex rounded off right away.
I had to cut them due to being bent to get them out.
Much easier if you take the spring out.
I found some used ones here on the forum
Had to double nut the top because the hex rounded off right away.
I had to cut them due to being bent to get them out.
Much easier if you take the spring out.
I found some used ones here on the forum
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Michael S. Palmer
Team Owner
Joined: May 2001
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From: Western NY
Try "warming" the bolt, and hold a small candle against it, melting the wax, so it seeps down into the threaded insert. This might penetrate the corrosion and provide some "lubricant" to allow you to turn the bolt. I don't know if they're still around, but at one time, there was a business called 'Hardbar', that sold adjustment bolts that had teflon pads, rather than the OE rubber.
Cruising
Joined: Jul 2023
Posts: 14
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From: London, Ontario, Canada
I just went through this. I took the spring out and soaked the bolts in PB blaster for a day or two, clamped the bolt down in my vice. It worked great on the one side, the other side the bolt sheared off and I had to drill out the damn thing.... good luck!!!!
Race Director
Joined: Oct 2004
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The stock bolts are pretty soft. Mine were actually bent. I soaked them with Kroil (I believe there are better penetrants now) and was finally able to break them free.
Had to double nut the top because the hex rounded off right away.
I had to cut them due to being bent to get them out.
Much easier if you take the spring out.
I found some used ones here on the forum
Had to double nut the top because the hex rounded off right away.
I had to cut them due to being bent to get them out.
Much easier if you take the spring out.
I found some used ones here on the forum
Last edited by grinder11; Aug 14, 2023 at 08:06 AM.
Race Director
Joined: Apr 2007
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From: South Western Ontario
Take the spring out, cut tight to the spring insert on the stud side then grab the big bushing head of the bolt with a small pipe wrench and try turning it out. Messing around under the car trying to do that is just a pain.
now, I suppose if you wanted to pull the suspension all apart to get the spring fully exposed you could, but it'd be easier to just pull the spring. You can take the spring out just by loosening the sway bar link and pilling the 2 lower control arm bolts.
now, I suppose if you wanted to pull the suspension all apart to get the spring fully exposed you could, but it'd be easier to just pull the spring. You can take the spring out just by loosening the sway bar link and pilling the 2 lower control arm bolts.