---
product_id: 32648339
title: "J-B Weld 2120 Radiator Repair Kit"
brand: "j-b weld"
price: "€ 39.00"
currency: EUR
in_stock: true
reviews_count: 13
category: "J B Weld"
url: https://www.desertcart.be/products/32648339-j-b-weld-2120-radiator-repair-kit
store_origin: BE
region: Belgium
---

# Complete kit with epoxy, fiberglass & tools Sets in under 1 minute Permanent professional-grade bond J-B Weld 2120 Radiator Repair Kit

**Brand:** j-b weld
**Price:** € 39.00
**Availability:** ✅ In Stock

## Summary

> 🛠️ Fix it once, fix it right—join thousands who trust J-B Weld’s legendary bond!

## Quick Answers

- **What is this?** J-B Weld 2120 Radiator Repair Kit by j-b weld
- **How much does it cost?** € 39.00 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.be](https://www.desertcart.be/products/32648339-j-b-weld-2120-radiator-repair-kit)

## Best For

- j-b weld enthusiasts

## Why This Product

- Trusted j-b weld brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Versatile & Reliable:** Works on plastic tanks, metal radiators, PVC, composites—ideal for pros and DIYers alike.
- • **All-in-One Repair Kit:** Includes epoxy putty, fiberglass cloth, sandpaper, and applicator for a pro finish every time.
- • **Precision Application:** Epoxy sets quickly—perfect for controlled, durable repairs up to 4" cracks or 3/8" holes.
- • **Effortless Leak Fixing:** No radiator or tank removal needed—repair leaks fast and hassle-free.
- • **Unmatched Bond Strength:** Trusted for 40+ years, delivers the world’s strongest, long-lasting seal.

## Overview

The J-B Weld 2120 Radiator Repair Kit is a professional-grade, all-in-one solution designed to permanently seal leaks in plastic and metal radiators without removal. Featuring a fast-setting epoxy putty combined with fiberglass cloth and essential tools, it repairs cracks up to 4 inches and holes up to 3/8 inch. Trusted for over 40 years, this kit offers unmatched bond strength and versatility for mechanics and DIY enthusiasts seeking a reliable, long-lasting fix.

## Description

Plastic Tank & Radiator Repair Kit. Works on Plastic Tanks & Metal Surfaces. Stops Leaks. No Removal Required.

Review: Use only small amounts, for it sets too quickly to do a complete job at once. - It works, if done correctly. Most important is making use of the mix within a minute. I benefitted from reading these reviews, learning how quickly it begins to set and the suggestion to mix only a small amount. I mixed four servings and still have half left over. I realized when working with my first mix, how quickly it sets, that its a setup for failure to mix the full amount of black and clear fluids as instructed in their package, for it's much more adhesive than what can be worked with effectively before it begins to set. Cutting off a small corner of each sealed package, I squeezed out a small amount from each onto a piece of cardboard - no bigger than a dime, keeping them separate from each other. This gave me time to wipe off the package corner and fold it over a couple times to seal it. Kept separate, the chemical action had not begun until I mixed the two with a popsicle stick. Both are quite fluid and spread out when squeeze out, so give them room to spread and not make contact. It's easy enough to see when there are about equal amounts, adding more to one or the other to make them look equal. It's an advantage not to use too much. My cardboard piece was the size of a business card, stiff enough where I could hold it flat, mix and scrape off the stick on the card edge and work that mix into the whole amount. Because one is black, the other clear, it's easy to see and judge how the two mix. Using the brush, I brushed it into the prepared surface, kind of scrubbing it in to invite the paste to mix with the radiator plastic, leveled it off with the brush, applied the precut piece of fiberglass mesh, then brushed a coat of the mix over the fiberglass. By this time, it was becoming obvious the mix was hardening and would no longer be as binding. Knowing I had planned to apply additional coats, I stopped working with it and let it set for about 15 minutes. The brush also set up and was no longer usable, which added to the misrepresentation of the instructions. It's quite fluid when mixed, so if applying a thick coat to a vertical surface, it will drain down, adding to the challenge of keeping it in place, applying the fiberglass and coating that and keeping that covering in place, all before it begins to set. Knowing I had planned on additional coats, I could concentrate on placement. Inspecting that first application after it set, I could see where I could improve upon the coverage and mixed up another serving, applying it with my rubber gloved little finger. Because of how fluid the mix is at the beginning, it kind of self levels, though not applying too much for it to run down. Initial preparation of the plastic tank is critical. I sanded the area, beyond the crack to invite bonding. I had two cracks to fix, one about 3/4" long on the flat surface just below the upper hose connection tube, the other, an inch long on the top of the tube, from the opening coming in. After sanding, I used a wood burning tool - the V tip, to melt the crack line, about 1/16th of an inch deep, then melted the plastic over the crack. When hardened, I sanded that surface to roughen it. I had no engine oil to clean off, so it was just cleaning off the sanding dust with a alcohol moistened lint free rag. My fiberglass application on the round upper radiator tube, created a ridge where the fabric ended. After my first application, I filed that edge to be round for the hose to seal right and sealed that off with my additional finger applied coat. My patches are holding for a week, with no sign of failure, with both looking so well glued in - especially the edges, that they should be a permanent part of the plastic radiator.
Review: Take your time. - I hit a turkey, and it cracked the top of my radiator!!! I cant notice the crack by eye, nor can I feel it with a fingernail.. But it does lose and spurts out coolant.. I' on a fixed income and can't afford a new radiator right now.. We are going on a trip next week, so I have my fingers crossed!! Fist off, I went through the process, laid down the fiberglass cloth and it looks nice!! And not one leak or spot of dampness!! First, carefully cut the 2 bags apart from each other, but do not cut them open!!! Sand sand sand, do a nice job... Clean it and the surrounding area really good... Alcohol, etc.. I used windex.. Cleaned it, dried if.. Then cut and shape your fiberglass cloth to size.. You want plenty of overlap over the crack or hole.. This is getting things ready.. Knead the black bag, unopened.. Mine was quite hard, but loosened up after kneading.. Cut the corners of each bag, about a quarter inch.. Here's the trick!!! Squeeze out just enough to do the job!! And do not squeeze them out on top of each other or let the black pile touch the clear pile... Once they touch, it starts the curing process.. They call for 50-50 of each, black and clear.. I used less clear in the mix.. The clear makes it harden faster.. Know where you're gonna put it before all this and get the right tool to mix and the right tool to spread or apply it. I used an old ins card to smooth and spread and a popsicle stick, to mix the two, together!! Mix the amount you need, and apply, spread it.. Put it in the cracks or holes and spread it fairly smooth.. While still wet and tacky, put the cloth on and quickly press the cloth into the mixture.. Smooth it out with whatever tool your using. Now, the cloth and jb weld should be pretty tacky.. Mix up the rest of the batch, in equal parts and spread it on top of the cloth, and be sure to overlap the cloth and area... Keep working on it neatly till its too stiff to work with.. Less than a min.. I let my repair sit over night, with the radiator cap off and the coolant, below the repair area.. Checked today, and it was hard as a rock.. Topped off the coolant, ran the car in idle, dry as a bone.. Then took it for a ride!!! Perfect so far... Moral of the story, watch out for turkeys!! Plan your repair.. Get your mixer, spreaders, cloth cut to size etc... And prepping of the surface.. JB weld always performs the best, but its up to you, to take your time prepping, follow directions, and have everything you need ready, BEFORE you cut those bags open... The brush that comes with the kit, use it with your last coat... To spread and smooth.. If you use it first it will be junk in 30 seconds.. I will let everyone know how it all holds up.. New post and update.. It has been about 2 weeks now.. No leaks.. None And this was including a 600 mile + trip... It included, high speed, 80+ to hills to traffic jams...! Not a leak or drop.. In the amount of time since using JB, I probably have put about 1000 on, and it works perfectly... Aug.12, 2023. Update.. Many more miles added and no leak, not a drop!!

## Features

- RADIATORWELD: Our radiator and plastic tank repair kit has all you need for making professional quality, permanent repairs with state of the art components and easy to follow instructions.
- COUNT ON US: For more than 40 years, our products have earned a loyal following from people who take pride in their work. With each product we innovate, we continue to provide the world's strongest bond for your projects.
- SIMPLE TO USE: No removal of tank or radiator is required to stop leaks. Easily fix holes up to 3/8" diam. or cracks up to 4" long. Includes epoxy putty, fiberglass cloth, sandpaper, and applicator.
- VERSATILE & DEPENDABLE: Great for radiators, washer fluid tanks, storage tanks, water tanks, plastics, composites, PVC and more. Professionals, mechanics and avid DIYers know J-B gets the job done.
- NO PROJECT TOO BIG OR TOO SMALL: We have all the products you need to get the job done right. JB Weld always delivers the legendary performance of the World's Strongest Bond.

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B01IOPE66G |
| Best Sellers Rank | #13,867 in Automotive ( See Top 100 in Automotive ) #2 in Radiator Sealers #723 in Oils & Fluids |
| Brand | J-B Weld |
| Brand Name | J-B Weld |
| Compatible Material | Metal |
| Customer Reviews | 4.1 out of 5 stars 1,067 Reviews |
| Global Trade Identification Number | 00043425021205 |
| Included Components | Epoxy Putty^Fiberglass Cloth^Sand Paper^Applicator Brush |
| Item Form | Liquid |
| Item Package Quantity | 1 |
| Item Type Name | Radiator and Plastic Repair Kit |
| Item Weight | 50 g |
| Manufacturer | JBWeld |
| Material | Plastic, Resin |
| Material Type | Plastic, Resin |
| Model | 2120 |
| Number of Pieces | 1 |
| Other Special Features of the Product | No Removal Required |
| Part Number | 2120 |
| Special Feature | No Removal Required |
| Specific Uses For Product | Repair |
| UPC | 043425021205 |
| Unit Count | 1 Count |
| Warranty Description | As Labelled |

## Product Details

- **Brand:** J-B Weld
- **Item Form:** Liquid
- **Material:** Plastic, Resin
- **Special Feature:** No Removal Required
- **Specific Uses For Product:** Repair

## Images

![J-B Weld 2120 Radiator Repair Kit - Image 1](https://m.media-amazon.com/images/I/71jfMGwMIFL.jpg)
![J-B Weld 2120 Radiator Repair Kit - Image 2](https://m.media-amazon.com/images/I/811dGeBkMrL.jpg)
![J-B Weld 2120 Radiator Repair Kit - Image 3](https://m.media-amazon.com/images/I/910wemEMChL.jpg)
![J-B Weld 2120 Radiator Repair Kit - Image 4](https://m.media-amazon.com/images/I/91BOjpX4AiL.jpg)

## Questions & Answers

**Q: Does this work on aluminum ?**
A: Yes, it is absolutely miraculous. It exceeded my expectations.

**Q: why it is temp fix? crack due to vibration? how long it can last?**
A: It will usually last a year as long as the car does not overheat which can cause too much pressure on the patched area

**Q: Does j-b weld 2120 really work on radiatots?**
A: It does if you work fast with it.

**Q: I have a leak on a small stem (i think is aluminum) at the seam that holds a small rubber hose that antifreeze runs though, the small stem gets hot.**
A: My honest opinion is this isn't going to work for your issue.... I used this on my plastic radiator at the top in small crack. It worked for couple weeks and had to buy new radiator...  don't waste your money

## Customer Reviews

### ⭐⭐⭐⭐⭐ Use only small amounts, for it sets too quickly to do a complete job at once.
*by H***E on August 17, 2020*

It works, if done correctly. Most important is making use of the mix within a minute. I benefitted from reading these reviews, learning how quickly it begins to set and the suggestion to mix only a small amount. I mixed four servings and still have half left over. I realized when working with my first mix, how quickly it sets, that its a setup for failure to mix the full amount of black and clear fluids as instructed in their package, for it's much more adhesive than what can be worked with effectively before it begins to set. Cutting off a small corner of each sealed package, I squeezed out a small amount from each onto a piece of cardboard - no bigger than a dime, keeping them separate from each other. This gave me time to wipe off the package corner and fold it over a couple times to seal it. Kept separate, the chemical action had not begun until I mixed the two with a popsicle stick. Both are quite fluid and spread out when squeeze out, so give them room to spread and not make contact. It's easy enough to see when there are about equal amounts, adding more to one or the other to make them look equal. It's an advantage not to use too much. My cardboard piece was the size of a business card, stiff enough where I could hold it flat, mix and scrape off the stick on the card edge and work that mix into the whole amount. Because one is black, the other clear, it's easy to see and judge how the two mix. Using the brush, I brushed it into the prepared surface, kind of scrubbing it in to invite the paste to mix with the radiator plastic, leveled it off with the brush, applied the precut piece of fiberglass mesh, then brushed a coat of the mix over the fiberglass. By this time, it was becoming obvious the mix was hardening and would no longer be as binding. Knowing I had planned to apply additional coats, I stopped working with it and let it set for about 15 minutes. The brush also set up and was no longer usable, which added to the misrepresentation of the instructions. It's quite fluid when mixed, so if applying a thick coat to a vertical surface, it will drain down, adding to the challenge of keeping it in place, applying the fiberglass and coating that and keeping that covering in place, all before it begins to set. Knowing I had planned on additional coats, I could concentrate on placement. Inspecting that first application after it set, I could see where I could improve upon the coverage and mixed up another serving, applying it with my rubber gloved little finger. Because of how fluid the mix is at the beginning, it kind of self levels, though not applying too much for it to run down. Initial preparation of the plastic tank is critical. I sanded the area, beyond the crack to invite bonding. I had two cracks to fix, one about 3/4" long on the flat surface just below the upper hose connection tube, the other, an inch long on the top of the tube, from the opening coming in. After sanding, I used a wood burning tool - the V tip, to melt the crack line, about 1/16th of an inch deep, then melted the plastic over the crack. When hardened, I sanded that surface to roughen it. I had no engine oil to clean off, so it was just cleaning off the sanding dust with a alcohol moistened lint free rag. My fiberglass application on the round upper radiator tube, created a ridge where the fabric ended. After my first application, I filed that edge to be round for the hose to seal right and sealed that off with my additional finger applied coat. My patches are holding for a week, with no sign of failure, with both looking so well glued in - especially the edges, that they should be a permanent part of the plastic radiator.

### ⭐⭐⭐⭐⭐ Take your time.
*by L***E on July 7, 2023*

I hit a turkey, and it cracked the top of my radiator!!! I cant notice the crack by eye, nor can I feel it with a fingernail.. But it does lose and spurts out coolant.. I' on a fixed income and can't afford a new radiator right now.. We are going on a trip next week, so I have my fingers crossed!! Fist off, I went through the process, laid down the fiberglass cloth and it looks nice!! And not one leak or spot of dampness!! First, carefully cut the 2 bags apart from each other, but do not cut them open!!! Sand sand sand, do a nice job... Clean it and the surrounding area really good... Alcohol, etc.. I used windex.. Cleaned it, dried if.. Then cut and shape your fiberglass cloth to size.. You want plenty of overlap over the crack or hole.. This is getting things ready.. Knead the black bag, unopened.. Mine was quite hard, but loosened up after kneading.. Cut the corners of each bag, about a quarter inch.. Here's the trick!!! Squeeze out just enough to do the job!! And do not squeeze them out on top of each other or let the black pile touch the clear pile... Once they touch, it starts the curing process.. They call for 50-50 of each, black and clear.. I used less clear in the mix.. The clear makes it harden faster.. Know where you're gonna put it before all this and get the right tool to mix and the right tool to spread or apply it. I used an old ins card to smooth and spread and a popsicle stick, to mix the two, together!! Mix the amount you need, and apply, spread it.. Put it in the cracks or holes and spread it fairly smooth.. While still wet and tacky, put the cloth on and quickly press the cloth into the mixture.. Smooth it out with whatever tool your using. Now, the cloth and jb weld should be pretty tacky.. Mix up the rest of the batch, in equal parts and spread it on top of the cloth, and be sure to overlap the cloth and area... Keep working on it neatly till its too stiff to work with.. Less than a min.. I let my repair sit over night, with the radiator cap off and the coolant, below the repair area.. Checked today, and it was hard as a rock.. Topped off the coolant, ran the car in idle, dry as a bone.. Then took it for a ride!!! Perfect so far... Moral of the story, watch out for turkeys!! Plan your repair.. Get your mixer, spreaders, cloth cut to size etc... And prepping of the surface.. JB weld always performs the best, but its up to you, to take your time prepping, follow directions, and have everything you need ready, BEFORE you cut those bags open... The brush that comes with the kit, use it with your last coat... To spread and smooth.. If you use it first it will be junk in 30 seconds.. I will let everyone know how it all holds up.. New post and update.. It has been about 2 weeks now.. No leaks.. None And this was including a 600 mile + trip... It included, high speed, 80+ to hills to traffic jams...! Not a leak or drop.. In the amount of time since using JB, I probably have put about 1000 on, and it works perfectly... Aug.12, 2023. Update.. Many more miles added and no leak, not a drop!!

### ⭐⭐⭐⭐⭐ Tip, using a piece of thin aluminum flat stock instead of the included fiberglass cloth
*by K***C on July 22, 2026*

Worked great to patch two pin hole leaks at the top of my radiator. Tip, using a piece of thin aluminum flat stock instead of the included fiberglass cloth will prevent the area of the leak from further flexing and eventually cracking the epoxied repair.

## Frequently Bought Together

- J-B Weld 2120 Radiator Repair Kit
- J-B Weld High Heat Epoxy Syringe, Dark Grey
- J-B Weld 8297 HighHeat 500 Degree Epoxy Putty Stick - 2 oz. , Grey

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*Product available on Desertcart Belgium*
*Store origin: BE*
*Last updated: 2026-08-18*