--- product_id: 7622563 title: "K&W 401016 Block Seal Permanent Metallic™ Block & Radiator Seal - 16 Oz" price: "146.20 DT" currency: TND in_stock: true reviews_count: 13 url: https://www.desertcart.tn/products/7622563-k-and-w-401016-block-seal-permanent-metallic-block-radiator store_origin: TN region: Tunisia --- # Withstands extreme pressure & temperature Compatible with all water-cooled engines Permanent molecular steel-strong bond K&W 401016 Block Seal Permanent Metallic™ Block & Radiator Seal - 16 Oz **Price:** 146.20 DT **Availability:** ✅ In Stock ## Summary > 🛡️ Seal it once, drive worry-free forever! ## Quick Answers - **What is this?** K&W 401016 Block Seal Permanent Metallic™ Block & Radiator Seal - 16 Oz - **How much does it cost?** 146.20 DT with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.tn](https://www.desertcart.tn/products/7622563-k-and-w-401016-block-seal-permanent-metallic-block-radiator) ## Best For - Customers looking for quality international products ## Why This Product - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - • **Steel-Strong Seal:** Forms a permanent molecular bond as tough as steel, ensuring long-lasting leak protection. - • **Extreme Condition Resilience:** Engineered to endure high pressure and temperature without washing away, keeping your cooling system intact. - • **Professional Grade Assurance:** Exceeds ASTM D6107 standards, trusted by mechanics and tested independently for peak performance. - • **Universal Engine Compatibility:** Seals cracks in cast iron, aluminum blocks, head gaskets, freeze plugs, and radiators across diesel and gasoline vehicles. - • **Easy Application, Lasting Results:** Simply add to your radiator and drive—stops leaks within 75 miles and seals permanently after 500 miles. ## Overview K&W 401016 Block Seal Permanent Metallic™ is a professional-grade, molecular-level sealant designed to permanently fix leaks in engine blocks, head gaskets, freeze plugs, and radiators. Compatible with all water-cooled diesel and gasoline vehicles, it withstands extreme pressure and temperature, surpassing ASTM D6107 standards. Trusted by mechanics and backed by independent testing, it offers a reliable, long-lasting solution to cooling system leaks with simple application and proven results. ## Description Forms a permanent molecular bond that's as strong as steel. Seals cracks & holes in cast iron & aluminum engine blocks, head gaskets, freeze plugs, & copper, aluminum & bi-material radiators & heater cores. Tested by an Independent test lab. Rated No.1 Review: Works great - Very good product Review: then fill it with tap water and then poor this bottle into the radiator cap opening - These do work! With certain assumption, depends on the leak or crack in your head gasket. I followed the directions from TrustMyMechanic . com in the you tube channel. [...] . His directions made more sense to me. You really have to drain your existing coolant out, flush it a couple of times, then fill it with tap water and then poor this bottle into the radiator cap opening. Then just drive your car for at least 500 miles. It took me about a week of driving to work and back to hit 500 miles. I check my radiator every day to top it off with water before going to work and noticed it stop leaking after about 75 miles on the odometer. So what does that mean...you really have to drive it around, get the engine hot enough and let the water/block seal get into the seams of the crack/leak. The directions on the bottle may work, but I think by doing it this way, I think it works a lot better. Like I said, it stopped leaking at around 75 miles into the 500 miles. I guess if you drive it over 500 miles and it is still leaking, then I think the crack/leak is way to big for this product to work. Or it could be leaking outside of the cylinder head. So after the 500 miles, verify that it stopped leaking by openning up your radiator cap and looking into your radiator. The top of the radiator should still be wet, there should still be water floating around at the top. If you can see the radiator fins and it's bone dry, then you still have a leak. If you are good, drain the tap water/block sealer, then flush it a couple of times. Then fill it up with coolant for your car. I use this product on a 2005 Toyota Tacoma Pre-Runner. Symptom of a crack/leak in your head gasket: Got a P0300 (random misfire), P0304 (cylinder 4 misfire), P0306 (cylinder 6 misfire). For this truck, when you drive it around town, you can hear water swooshing back and forth inside the engine bay. This is because when there is a leak in the gasket, the pressure and gases from the cylinder head pushes back into the coolant chambers and creates bubbles/air pockets thus there is open space in your coolant block that allows the coolant to move around. So if you hear that, it's an indication that you got coolant issues. Also, you will be losing coolant everyday or two when you check your radiator. Hope that helps... ## Features - Permanent molecular seal that’s as strong as steel - Seals cracks & holes in cast iron and aluminum engine blocks, head gaskets, freeze plugs, and copper, aluminum and bi-material radiators & heater cores - For use in all water-cooled diesel and gasoline vehicles - Withstands extreme pressure and temperatures of a cooling system and will not wash away - Professional grade formula exceeds ASTM D6107 for effectively sealing leaks in cooling systems ## Technical Specifications | Specification | Value | |---------------|-------| | Customer Reviews | 4.1 out of 5 stars 390 Reviews | ## Images ![K&W 401016 Block Seal Permanent Metallic™ Block & Radiator Seal - 16 Oz - Image 1](https://m.media-amazon.com/images/I/719Ox96ysYL.jpg) ## Available Options This product comes in different **Number Of Items** options. ## Questions & Answers **Q: How is this one different from another orange can with the same product title, also sold at Amazon?** A: If you provide a link I would be happy to see if there is a difference. I do not find a single can listed with this same title. I see a 6 pack. **Q: how about if you can’t take off thermostat.. cause my truck Thermostat come with it 2005 Dodge ram 1500** A: I didn’t take off my thermostat. All I did was drain the existing coolant, fill it up with tap water half way then add the CRC bottle and then top off the water. Drive it around for a week or two (500 miles). Check the radiator daily before you head out and if it does down fill it up with water. After a week of driving you will notice that the water in the radiator will stop leaking (if it works). Once it stops leaking for a couple of days then you can drain it again, flush it out with water then add in your coolant again. **Q: can we pour it into the overflow reservoir?** A: If I remember it's a big no on that. Take off the top hose of radiator and pour it in the hose. But you want to have room for it to flow into radiator. I think it was kinda thick so mix it with hot water then add to hose. That's my two cents. **Q: will it stop water to oil leak?** A: I don’t think so....think of it this way, the coolant has to leak into the combustion chamber for it to work. The high heat will fuse the particle together at the crack and eventually plug up the leak. You would have to leave it in your coolant for approx 500 miles. That will give it time for this mixture to travel into your cylinder, heat up and plug up the leak. Actually for me it only took about 200 miles and I noticed the water in the radiator stopped leaking (I check it every morning before driving out). ## Customer Reviews ### ⭐⭐⭐⭐⭐ Works great *by G***E on September 11, 2025* Very good product ### ⭐⭐⭐⭐⭐ then fill it with tap water and then poor this bottle into the radiator cap opening *by T***T on December 16, 2014* These do work! With certain assumption, depends on the leak or crack in your head gasket. I followed the directions from TrustMyMechanic . com in the you tube channel. [...] . His directions made more sense to me. You really have to drain your existing coolant out, flush it a couple of times, then fill it with tap water and then poor this bottle into the radiator cap opening. Then just drive your car for at least 500 miles. It took me about a week of driving to work and back to hit 500 miles. I check my radiator every day to top it off with water before going to work and noticed it stop leaking after about 75 miles on the odometer. So what does that mean...you really have to drive it around, get the engine hot enough and let the water/block seal get into the seams of the crack/leak. The directions on the bottle may work, but I think by doing it this way, I think it works a lot better. Like I said, it stopped leaking at around 75 miles into the 500 miles. I guess if you drive it over 500 miles and it is still leaking, then I think the crack/leak is way to big for this product to work. Or it could be leaking outside of the cylinder head. So after the 500 miles, verify that it stopped leaking by openning up your radiator cap and looking into your radiator. The top of the radiator should still be wet, there should still be water floating around at the top. If you can see the radiator fins and it's bone dry, then you still have a leak. If you are good, drain the tap water/block sealer, then flush it a couple of times. Then fill it up with coolant for your car. I use this product on a 2005 Toyota Tacoma Pre-Runner. Symptom of a crack/leak in your head gasket: Got a P0300 (random misfire), P0304 (cylinder 4 misfire), P0306 (cylinder 6 misfire). For this truck, when you drive it around town, you can hear water swooshing back and forth inside the engine bay. This is because when there is a leak in the gasket, the pressure and gases from the cylinder head pushes back into the coolant chambers and creates bubbles/air pockets thus there is open space in your coolant block that allows the coolant to move around. So if you hear that, it's an indication that you got coolant issues. Also, you will be losing coolant everyday or two when you check your radiator. Hope that helps... ### ⭐ Past shelf life when delivered *by R***P on February 17, 2024* After lots or research, I settled on this product, prepared me vehicle and waited for a week for it to show up. When it arrived I followed the instructions to a tee, when I opened the can and poured it into the gallon just, after vigorously shaking it as per the instructions, the business part of the product had solidified in the bottom of the can rendering completely useless. DO NOT WASTE YOUR MONEY ## Frequently Bought Together - CRC K&W 401016 Block Seal Permanent Metallic™ Block & Radiator Seal - 16 Oz - BlueDevil Products 00203 Radiator Flush & Oil Degreaser - 1 Quart - K&W 401232 Permanent Head Gasket & Block Repair with Nanotechnology - 32 Fl Oz --- ## Why Shop on Desertcart? - 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016 - 🌍 **Shop Globally** — Access 737+ million products across 21 categories - 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price - 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members) - 🔒 **Secure Payments** — Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.tn/products/7622563-k-and-w-401016-block-seal-permanent-metallic-block-radiator](https://www.desertcart.tn/products/7622563-k-and-w-401016-block-seal-permanent-metallic-block-radiator) --- *Product available on Desertcart Tunisia* *Store origin: TN* *Last updated: 2026-06-11*