---
product_id: 5618885
title: "ST5501 Multi-Purpose One Step Coolant Leak Repair, 8oz, Pour and Go, Mixes with All Antifreeze, No Flushing Required"
brand: "k-seal"
price: "€ 26.15"
currency: EUR
in_stock: true
reviews_count: 13
category: "K Seal"
url: https://www.desertcart.pt/products/5618885-st5501-multi-purpose-one-step-coolant-leak-repair-8oz-pour
store_origin: PT
region: Portugal
---

# Compatible with all antifreeze types One-step, no flushing required Seals leaks in 1-3 minutes ST5501 Multi-Purpose One Step Coolant Leak Repair, 8oz, Pour and Go, Mixes with All Antifreeze, No Flushing Required

**Brand:** k-seal
**Price:** € 26.15
**Availability:** ✅ In Stock

## Summary

> 🚗💨 Seal it fast, drive smarter—because leaks don’t wait!

## Quick Answers

- **What is this?** ST5501 Multi-Purpose One Step Coolant Leak Repair, 8oz, Pour and Go, Mixes with All Antifreeze, No Flushing Required by k-seal
- **How much does it cost?** € 26.15 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.pt](https://www.desertcart.pt/products/5618885-st5501-multi-purpose-one-step-coolant-leak-repair-8oz-pour)

## Best For

- k-seal enthusiasts

## Why This Product

- Trusted k-seal brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **One-Step Pour & Go:** No flushing, no mess—just add and get back on the road fast.
- • **Rapid Leak Sealing:** Fix radiator, head gasket & more in minutes—no downtime, no hassle.
- • **Proven Global Trust:** Over 8 million bottles sold worldwide—join the elite drivers who never stall.
- • **Engine Efficiency Preserved:** Seals leaks without compromising your cooling system’s performance.
- • **Universal Coolant Compatibility:** Works seamlessly with every antifreeze formula—drive worry-free.

## Overview

K-Seal ST5501 is a compact, 8oz liquid coolant leak repair solution that quickly seals holes and cracks in water-cooled engines within 1-3 minutes. Compatible with all antifreeze types and suitable for cars and light trucks up to 12 cylinders, it requires no flushing and preserves engine cooling efficiency. Trusted globally with over 8 million bottles sold, it’s the go-to fix for fast, reliable radiator and gasket leak repairs.

## Description

Buy K-Seal ST5501 Multi-Purpose One Step Coolant Leak Repair, 8oz, Pour and Go, Mixes with All Antifreeze, No Flushing Required: Cooling System - desertcart.com ✓ FREE DELIVERY possible on eligible purchases

Review: This stuff is liquid gold, only cheaper! Try it! - I have a 2000 Pontiac Grand AM GT V6 3400 engine, bought the car new from the dealer. A few years back the engine developed a coolant leak in the lower intake manifold, discovered oil in the coolant and needed to fill the radiator tank every couple of weeks. I had a mechanic remove the intake and replace the gaskets; he also suggest I have the heads removed and new head gaskets installed while he had it apart. $1,500 later it was back together and running great, no more leaks. Fast forward about 10K miles and a little over a year later, out of warranty I may add, the engine would smell of coolant and started to leak externally. I was going through a gallon a coolant every couple weeks. Take into account this car has about 100K miles and has a market value of about $1,800. I wasn't going to throw anymore money after bad. So I kept driving it, but one morning I started it up cold and the engine began to miss on 1 or 2 cylinders, the check engine was flashing, indicated the misfiring cylinders. I towed it to another mechanic to see what the cause was, turns out the head gasket was blown this time, compression test proved his theory, he suggested I get another engine from a junked used car and try my luck. That would cost about $3,000 with parts and labor. Not about to throw any more money away, I had the car towed back to my house where it sat for a few months. Not sure what to do with this car, body, paint and interior was in excellent condition, oil was always changed with Mobile 1, it was a well maintained car, was a shame to see it there dead in the driveway. Just had new tires and brakes installed prior to the coolant leak. One day I ran across an article promoting K-Seal, after reading the great reviews here on desertcart, I figured what the heck. It was either call the junk yard and have them pick up the car or spend less than the cost of lunch and give it a shot. Can't believe how easy it was to do, I pulled the radiator hose from the engine block, poured in the K-Seal and reinstalled the hose. The directions state you do not have to drain the coolant like other brands require. Started the car up, and of course the engine was misfiring and check engine light began to flash like before. I let it idle for a few minutes to warm up, when it got to operating temperature, I took it for a drive around the neighborhood. Within about a mile of driving, the engine smoothed out and the CE light went dark. Drove around for another 20 minutes and returned home. I parked the car and check underneath to see if the coolant was leaking like before, to my surprise it had stopped! I let the engine cool and topped off the coolant reservoir with fresh antifreeze until full. I decide to drive the car to work the next day, a 35 miles commute one way into the city, in the middle of summer, ran flawless. Wow! Absolutely no problems since the K-Seal treatment. I have been driving the car now for 7 months and about 6K miles. The coolant hasn't leak a bit and the car runs flawless.Even my mechanic can't believe this stuff actually worked. I am a believer and have since told many people of my experience with this product. Had a buddy with a similar issue with his beloved 2 DR Accord V6, fixed his leak too! I normally don't spend the time to write reviews, but this product truly has made a believer out of me. What do you have to lose? I almost threw away my car, and for a measly few dollars it is now back on the road better than ever. Thank you K-Seal ! I want to add that after reading the one star reviews on this forum that these people were not using the product as intended. It is designed to very small leaks like in gaskets and cracks in the engine block of heads. It needs high heat to cure the fine copper powder that forms a new gasket. If you have a large leak in a radiator, heater core or hose, it's probably not going to work for very long if at all, better off replacing them. Now head gaskets, yes give it a shot! UPDATE: 9/9/16 Still no leaks, I've clocked 20K+ miles on K-Seal with no issues. Hoping for another 20K... buy this stuff. UPDATE: 1/11/17 Well, the engine miss has returned, anti-freeze is disappearing again, head gasket is leaking again. Just poured another bottle of K-Seal in again, within 5 minutes the leak is repaired again. This stuff is great, my old beater is good for another 20K I hope. Money saved again! My mileage on the first repair was 23K miles, not bad for a $11 fix.
Review: This amazing product works, we are so happy! - We had a significant leak. Mechanic charged us to look at the car and said he'd apply that charge to the repair. His quote was well over $1000 so we got the car back from him, paid his fee and took a chance ordering this product. We were surprised at how small the bottle is. We were a bit doubtful but we put this directly in the radiator and it slowed down the leak considerably. We decided to order a second bottle and put it in the reservoir this time. Both times we followed all instructions carefully (we watched videos on how to use it) and drove around afterwards. Our 2007 car has been leak-free for over six months and is still going strong. This incredible product has saved us so much money.

## Features

- FIX IT FAST: Our multi-purpose solution works in minutes to quickly seal leaks in the radiator, head gasket, freeze plugs, block, heater matrix & water pump. Fixes most leaks in water-cooled engines
- STOP HOLES & CRACKS: With just 1 step our unique formula will seek out each hole & crack, sealing them, without any adverse impact on the efficiency of your engine cooling
- VERSATILE COMPATIBILITY: Compatible with all types of antifreeze coolant. Suitable for use in both cars & light trucks with up to 12 cylinders.
- Attention: If you notice bubbles coming from the radiator or coolant reservoir, or if K-Seal engine coolant stop leak is not sealing, the system might be over-pressurized. Refer to the Product guides and documents section of this page for additional instructions to ensure a successful repair. Over 8 million bottles sold worldwide!

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B001QT9KO6 |
| Best Sellers Rank | #2,084 in Automotive ( See Top 100 in Automotive ) #1 in Cooling System Additives |
| Brand | K-Seal |
| Brand Name | K-Seal |
| Color | BLUE |
| Compatible Material | All Types of Antifreeze / Coolant and Other Additives |
| Customer Reviews | 4.3 out of 5 stars 13,484 Reviews |
| Global Trade Identification Number | 05060002968017 |
| Included Components | K-Seal ST5501 Multi-Purpose One Step Coolant Leak Repair, 8oz |
| Item Dimensions | 3.35 x 1.5 x 4.33 inches |
| Item Form | Liquid |
| Item Type Name | Engine Coolant Leak Repair |
| Item Weight | 0.26 kg |
| Item dimensions L x W x H | 3.35 x 1.5 x 4.33 inches |
| Manufacturer | Solv-Tec |
| Material | Plastic |
| Material Type | Plastic |
| Model | ST5501 |
| Number of Items | 1 |
| Number of Packs | 1 |
| Part Number | ST5501 |
| Style | Compact |
| Style Name | Compact |
| Surface Recommendation | Metal |
| UPC | 367157659506 812646010004 |
| Unit Count | 1 Count |
| Warranty Description | Leak will stop within 1-3 minutes. |
| Water Resistance Level | Waterproof |

## Product Details

- **Brand:** K-Seal
- **Item Weight:** 0.26 kg
- **Item dimensions L x W x H:** 3.5 x 1.5 x 4.5 inches
- **Material:** Plastic
- **Style:** Compact

## Images

![ST5501 Multi-Purpose One Step Coolant Leak Repair, 8oz, Pour and Go, Mixes with All Antifreeze, No Flushing Required - Image 1](https://m.media-amazon.com/images/I/71fLFvkh6wL.jpg)

## Questions & Answers

**Q: will this work for leakey gaskets?**
A: It is designed to work on leaky gaskets.  If you have a small leak this product might be an easy and cheap fix.  It did not work for me.  Perhaps my leak was too large.  It is hard to tell.

**Q: Does it discolor the antifreeze? Thanks**
A: Unfortunately I can't say.  I have a GM vehicle that uses the orangish color engine coolant and it and this product are so close in color it's hard to say if it would discolor the usual green-colored coolant found in non-GM vehicles.  The other challenge is that I can only look at the coolant through an overflow reservoir and it's so dark when I look inside (I have to use an LED flashlight to see it adequately) that it would be hard to tell if there was any discoloration.

**Q: Can you use this in a 2013 escape?**
A: You can use it anywhere.  It's kept my 1998 Chevy Lumina going over 2 years with almost 178,000 miles on it!

**Q: can you mix this with barstop if you all ready put that in the radiator?**
A: I did mix this with Irontite All Weather Seal. Did the K-seal first. Irontite a week later. Just to be sure. Since they both said it can remain in the system. Two weeks, still good.

## Customer Reviews

### ⭐⭐⭐⭐⭐ This stuff is liquid gold, only cheaper! Try it!
*by R***T on December 1, 2015*

I have a 2000 Pontiac Grand AM GT V6 3400 engine, bought the car new from the dealer. A few years back the engine developed a coolant leak in the lower intake manifold, discovered oil in the coolant and needed to fill the radiator tank every couple of weeks. I had a mechanic remove the intake and replace the gaskets; he also suggest I have the heads removed and new head gaskets installed while he had it apart. $1,500 later it was back together and running great, no more leaks. Fast forward about 10K miles and a little over a year later, out of warranty I may add, the engine would smell of coolant and started to leak externally. I was going through a gallon a coolant every couple weeks. Take into account this car has about 100K miles and has a market value of about $1,800. I wasn't going to throw anymore money after bad. So I kept driving it, but one morning I started it up cold and the engine began to miss on 1 or 2 cylinders, the check engine was flashing, indicated the misfiring cylinders. I towed it to another mechanic to see what the cause was, turns out the head gasket was blown this time, compression test proved his theory, he suggested I get another engine from a junked used car and try my luck. That would cost about $3,000 with parts and labor. Not about to throw any more money away, I had the car towed back to my house where it sat for a few months. Not sure what to do with this car, body, paint and interior was in excellent condition, oil was always changed with Mobile 1, it was a well maintained car, was a shame to see it there dead in the driveway. Just had new tires and brakes installed prior to the coolant leak. One day I ran across an article promoting K-Seal, after reading the great reviews here on Amazon, I figured what the heck. It was either call the junk yard and have them pick up the car or spend less than the cost of lunch and give it a shot. Can't believe how easy it was to do, I pulled the radiator hose from the engine block, poured in the K-Seal and reinstalled the hose. The directions state you do not have to drain the coolant like other brands require. Started the car up, and of course the engine was misfiring and check engine light began to flash like before. I let it idle for a few minutes to warm up, when it got to operating temperature, I took it for a drive around the neighborhood. Within about a mile of driving, the engine smoothed out and the CE light went dark. Drove around for another 20 minutes and returned home. I parked the car and check underneath to see if the coolant was leaking like before, to my surprise it had stopped! I let the engine cool and topped off the coolant reservoir with fresh antifreeze until full. I decide to drive the car to work the next day, a 35 miles commute one way into the city, in the middle of summer, ran flawless. Wow! Absolutely no problems since the K-Seal treatment. I have been driving the car now for 7 months and about 6K miles. The coolant hasn't leak a bit and the car runs flawless.Even my mechanic can't believe this stuff actually worked. I am a believer and have since told many people of my experience with this product. Had a buddy with a similar issue with his beloved 2 DR Accord V6, fixed his leak too! I normally don't spend the time to write reviews, but this product truly has made a believer out of me. What do you have to lose? I almost threw away my car, and for a measly few dollars it is now back on the road better than ever. Thank you K-Seal ! I want to add that after reading the one star reviews on this forum that these people were not using the product as intended. It is designed to very small leaks like in gaskets and cracks in the engine block of heads. It needs high heat to cure the fine copper powder that forms a new gasket. If you have a large leak in a radiator, heater core or hose, it's probably not going to work for very long if at all, better off replacing them. Now head gaskets, yes give it a shot! UPDATE: 9/9/16 Still no leaks, I've clocked 20K+ miles on K-Seal with no issues. Hoping for another 20K... buy this stuff. UPDATE: 1/11/17 Well, the engine miss has returned, anti-freeze is disappearing again, head gasket is leaking again. Just poured another bottle of K-Seal in again, within 5 minutes the leak is repaired again. This stuff is great, my old beater is good for another 20K I hope. Money saved again! My mileage on the first repair was 23K miles, not bad for a $11 fix.

### ⭐⭐⭐⭐⭐ This amazing product works, we are so happy!
*by A***R on July 13, 2026*

We had a significant leak. Mechanic charged us to look at the car and said he'd apply that charge to the repair. His quote was well over $1000 so we got the car back from him, paid his fee and took a chance ordering this product. We were surprised at how small the bottle is. We were a bit doubtful but we put this directly in the radiator and it slowed down the leak considerably. We decided to order a second bottle and put it in the reservoir this time. Both times we followed all instructions carefully (we watched videos on how to use it) and drove around afterwards. Our 2007 car has been leak-free for over six months and is still going strong. This incredible product has saved us so much money.

### ⭐⭐⭐⭐⭐ converted skeptic -- VW Passat
*by S***N on July 18, 2011*

I had a little pin hole leak in my radiator on my 2002 VW Passat wagon (130k miles). It was somewhere in the fins so it wasn't something I could do a JB weld fix on. While i was contemplating spending the six hundred bucks in [parts and labor to replace the radiator, i just kept adding more coolant. It wasn't a really bad leak. Mostly just annoying because of the smell of burning radiator fluid. But after about a week, it just stopped leaking on it's own, so I've been driving around town with my fingers crossed hoping it would not start leaking again. But then we had planned a family trip out to New Mexico from KC. It was about 110 degrees F out and 1,400 miles to cover round trip with very long stretches of highway cutting thought the middle of nowhere, with absolutely nothing around for miles, so the idea that the radiator would probably choose this time to start leaking again was a serious concern to me. Yes, technically I should have just replaced the radiator, but instead i decided to just bring a couple of gallons of pre-mixed coolant along and ordered a bottle of K-Seal to take along as a "just in case" precaution. Sure enough about half way out there the radiator started to leak again. This time worse than before. So i carefully followed the directions, shaking the bottle of K-Seal but poured only about half of the bottle into the reservoir/overflow tank (the bottle said it would treat up to 10 cylinders and worked on cracked cylinder heads and engine blocks, so i figured half a bottle would be plenty for a little radiator pinhole) As other reviewers have observed it does come out as a thickish ugly brown liquid that just sits there in the bottom of your overflow tank. Which is admittedly kind of scary, especially if you are skeptical of these products to begin with. But shortly after the car was up to temperature, the leak stopped, as advertised -- even though the k-seal was still very noticeably sitting at the bottom of the overflow tank. VW antifreeze is reddish pink and the K-seal at the bottom was a darker brown. After driving the rest of the way out there it had mixed with the rest of the coolant so it didn't look as nasty in the tank. I've driven another 1600 miles on it and not had any issues. I think the biggest fear with these types of "sealer" products is not that they will not actually seal the leak, but that they will gum up all the intricate little passageways in your heater core, and the rest of your cooling system, but I haven't had any issues at all with this. If I do, I'll be sure to post back and downgrade my 5-star rating. So, I'm sold. this stuff saved my butt and I would definitely recommend it -- especially if you're in a bind. I would never use this (or any other product like this) as a preventative measure like some of the product testimonials on the K-Seal web site, but if you have an older car that you don't want to dump a bunch of money in for repairs, I'd definitely give this a go.

## Frequently Bought Together

- K-Seal ST5501 Multi-Purpose One Step Permanent Coolant Leak Repair, 8oz, Pour and Go, Mixes with All Antifreeze, No Flushing Required
- PEAK 50/50 Prediluted Antifreeze and Coolant for All Engine Cooling Systems
- K-Seal ST3501 Pour and Go Head Gasket Sealer, 16oz, Permanent Repair for Blown Head Gaskets, Cracked Heads and Blocks

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*Product available on Desertcart Portugal*
*Store origin: PT*
*Last updated: 2026-10-01*