|Item Weight||9.6 ounces|
|Product Dimensions||7.87 x 2 x 6 inches|
|Item model number||ST5501|
|Is Discontinued By Manufacturer||Yes|
|Manufacturer Part Number||ST5501|
K-SEAL Coolant Leak Repair, ST5501 8oz, Multi-Purpose Formula Stops Leaks in the Radiator, Head Gasket, Block, Water Pump Casing, Heater Core, and Freeze Plug - Pour and Go - Trade Trusted-Stop Leak
|Price:||FREE Shipping on your first order. Details & FREE Returns|
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- REPAIRS IN MINUTES: Formulated to permanently weld radiators, including hard plastic aluminum heads and blocks in old and new cars. The only car radiator and gasket sealant university tested to meet ASTM D3147. Save time/money. US Bestseller
- SEALS CRACKS AND STOPS LEAKS: A DIY alternative to costly repairs, our coolant leak fix permanently seals cracks and holes! It quickly repairs your leaking radiator, freeze plug, heater core and water pump casing with no adverse impact on efficiency.
- POUR AND GO: Our cooling system sealer is easy to use: just shake the bottle, add to your radiator/overflow and run the engine! Unlike some traditional products, it mixes with all types of antifreeze, absolutely no draining or flushing required.
- SCIENTIFICALLY TESTED: Safe and effective, our cracked block repair can seal leaks up to 1/32 of an inch! Once cured, the repair withstands the high pressure of the combustion chamber, all without failing or clogging the cooling system.
- CUSTOMER SUPPORT: If K-Seal engine coolant leak stop doesn’t seal, the system might be over-pressurized. Check the Technical Specification section of this page for extra instructions for a successful repair. Over 8 million bottles sold worldwide!
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K-Seal 8 fluid ounce bottle is effective to 20 quarts cooling capacity. Just shake, pour and go. It repairs leaks and cracks in radiator, head gasket, heater core, freeze plugs, water pump casing, cylinder heads and engine blocks.
From the manufacturer
The Safe and Easy Way to Fix a Coolant Leak
The secret behind K-Seal’s ability to repair a coolant leak is down to its contents: a specially developed blend of chemical ingredients including ceramic microfibers and copper particles. When added to the cooling system the ingredients disperse and flow freely around the system suspended in the coolant. If coolant is leaking from the system, either externally or internally across the head to the cylinders, then K-Seal will follow it through the hole or crack and try to fix the leak.
Permanent Coolant Leak Repair with K-Seal
Just Pour & Go
Coolant leaks don’t have to result in costly repair bills – simply add K-Seal to your coolant system for a quick and permanent fix. K-Seal is trusted by millions of customers worldwide, and the only coolant leak repair fluid carried by the AA, the UK’s largest roadside repair company.
K-Seal couldn’t be simpler to use. K-Seal’s unique formula will seek out holes and cracks, and permanently seal them, with no adverse impact on the efficiency of your engine cooling.
- Fixes most leaks in water-cooled engines
- Permanent repair, guaranteed for the lifetime of the engine
- Trusted by professionals
Coolant System Sealer
Just Pour & Go
Once the crack or hole has been located, the microfibers instantly begin to mesh together within the gap, building a seal literally fiber by fiber to stop the coolant leaking through the gap.
The particles in our K-Seal products are very precisely designed to be large enough to repair holes up to 0.635mm in size but deliberately small enough to never block any passageways or tubes within the cooling system, including those inside the heater core and radiator.
Once the microfibers have sealed and fixed the leak, a combination of exposure to either the external atmosphere or the gases within the combustion chamber and the heat within the cooling system and engine causes the K-Seal formula to cure. This results in an extremely strong and permanent seal able to withstand even the high pressures from the combustion chamber. This is how K-Seal Ultimate is able to repair head gasket failures, even where the cooling system is being over-pressurized exhaust gases entering the system
Common Coolant Leaks
K-Seal can deal with all of these leaks and more, as long as they are identified as early as possible. It is easy to use – simply shake it and pour it into the coolant mixture and it will work automatically.
Types of leaks that can occur within your car’s engine
- Head gasket leak, where the coolant is allowed to enter the engine cylinder
- Engine block leak, where the stressed metal cracks and leaks coolant
- Water pump leak, where leaks develop under stress or abrasion and coolant leaks out
- Radiator leak, where circulating coolant leaks and causes the engine to overheat
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However, before installation, I thought to myself..."I get 20% off anything I buy...why not spend the extra $11-12 to get this little bottle of supposed magic and then laugh when it doesn't work, eat the cost, and then treat myself to a new radiator?" I mean, that's literally the worst that could happen. The best obviously me not needing the radiator anymore. I was attracted to this product for a number of reasons:
1. A very low price. $15 full price compared to other competing products ranging from $30-$60.
2. Billed as not just a stop leak for the radiator, but the head gasket & heater core and pretty much everything else relating to the cooling system. Since I had no idea where this leak was, this was important to me.
3a. A literal "Pour-N-Go". Pour it in with existing antifreeze, let it idle for a little bit (5-8 minutes, compared with similar products' 50-ish) AND no need to flush afterwards. You can absolutely leave it for the remainder of the coolant's lifespan.
3b. Touching further on 3a, it is actually a good idea to leave it in "for future repairs." Preventative maintenance to a T.
4. Small size. Usually I'd say bigger is better, but for additives where [grossly] overfilling can be a dangerous/hazardous issue, something that does its job while taking up a small amount of space is very important.
...however, I highly believed that it would not work & I'd've just wasted my money. In my training at AutoZone, I was taught that if your coolant was leaking out completely in faster than 2 weeks, then stop leak was more than likely a waste of money. If I was LUCKY, my coolant would stay in for 2 DAYS. I had recently replaced my radiator cap, which kept it from leaking out within half a day and making steam come from under the hood. So I didn't need to, but I would recommend you replace your radiator cap before you try this, or if you know it's bad enough, in conjunction with the K-Seal unless you've replaced your radiator cap within no more than the past 2 years.
I literally did this in the parking lot of AutoZone on my day off with my store manager and other fellow coworkers watching. Here's what I did, after grabbing my funnel specifically for adding coolant.
1. I topped off my coolant reservoir with fresh coolant (since mine was all gone) to the full line with the engine completely cold. It's a good idea to wait 30 minutes or more for this to happen after driving. Luckily, I had a suitable place to loiter and cause mischief and make conversation. I do recommend you let your coolant run completely dry (or at least down to the "LOW/FILL" line). I had the luxury(?) of not needing to wait for that, the coolant was pre-gone a long time ago. Just get the cheapest compatible 50/50 coolant you can get for your vehicle; they are literally all the same with literally zero difference between any brands besides packaging (and maybe Peak's "Lifetime Radiator Guarantee"). The only difference that matters is what color your coolant is. If your coolant is completely gone and you drive a GM vehicle, there is no harm in putting in the yellow coolant instead of the pink/red Dex-Cool stuff. Just don't mix yellow & red actively. Also, just get it pre-mixed. It'll be exactly half coolant and half DILUTED water. Don't chance mixing it yourself, especially if you don't have to.
2. I shook the bottle of K-Seal vigorously for a little over 30 seconds. YOU MUST SHAKE IT. So shake it like a Polaroid picture! Have fun while doing it, too! Dance while doing it to make fixing your radiator fun!
3. After placing my funnel in the coolant reservoir again, I simply poured in the K-Seal. It ended up being a noticeable amount past the full line, but nothing too serious, and since the coolant is now less parts coolant, likely no BFD. The bottle states that you can go directly through the radiator cap or use the overflow reservoir, but that the reservoir is going to take a little longer. I opted for the reservoir in case there were any leaks from my reservoir to the actual radiator. This is what I would recommend doing only unless you simply do not have a reservoir tank. Sure, it takes a little longer, but why would you want to rush perfection? 5-10 minute oil changes are scams - it takes 20-25 minutes at least to properly (and thoroughly) do an oil change. Same applies here. For best results, take the extra time now so you don't have to take even more time later.
4. Run your engine for 20 minutes (since it takes longer through the overflow tank). It'll take 5 minutes for your engine to reach operating temperature. After that 5 minute mark, run your heat with the A/C on full go for 10 minutes (if it's getting too hot in there, you can always step outside. I was for almost the entire portion of this anyhow), then shut it off for the final 5. The heat & A/C go on so that the K-Seal can circulate through the heater core. Mine to my knowledge wasn't leaking, but regardless of whether your floorboards are soaked in coolant or not, it's probably a good idea to do this, because, well, read the last part of Step 3. Oh, and make sure you have enough gas in your tank for this, obviously. 1/4 of a tank should be plenty, so if it's under 1/4 a tank, get it up there.
5. Drive, and try to drive a little aggresively. Get out on fast roads and hit the highway. Drive for how long you like, I drove for about 10 miles in a circle round back to AutoZone.
6. Park your car, let it sit for 5-10 minutes, pop the hood, and (hopefully) be amazed at seeing your coolant still at the level you left it.
7. Go about your day(s), checking routinely, and especially take note of where you're at after 100 miles. It may have continued leaking a little bit, but hopefully not down past the low line. Mark the level with a fine-line Sharpie for reference after another 100 miles.
8. Check again after another 100 miles. See that it doesn't budge. If it had leaked out a little before this but hasn't budged since, top off to the full line, because you're patched up for good! If it's still leaking, constantly monitor until/if it gets down to the Low line, top it off, keep monitoring, and if it gets to the Low line again, you have a leak too big for this to handle, surprisingly.
9. If you're all good now, return that +$130 radiator and use it for a vacation/weekend getaway that you can now afford to drive a long distance to!
10. Write your review on Amazon, letting the good people of the intrawebs know of your experience.
So, in conclusion, this product completely worked for me when I did not at all expect it to. It is a darn good product at an amazing price, and therefore definitely worth a shot before replacing components of your engine cooling system. I had good results, and anticipate continued performance. The only negative I could possibly see from my experience was that it took a little longer to completely do its job than I had anticipated, but I had a huge leak, and very noticeable results were immediate. I have not noticed anything having been clogged, as is a common concern with these types of products. If anything does go wrong, I shall be sure to note it in this review and adjust my rating accordingly.
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I watched several YouTube videos and came across one that advises: 1. You don't need to pour the whole bottle. 2. Shake for 1-2 minutes (there are bits of something or other like metal or whatever inside) and mix with coolant and then pour into coolant reservoir tank. I had an active leak that dripped under the drivers side every 5 seconds!!
I moved the vehicle about 2 feet, placed a fresh piece of cardboard box to determine old -vs- new drips. I used a clean plastic 2 liter soda bottle and poured 1/3 of K-Seal and filled the rest of the way with coolant. Started it up and waited - got out to check and there was some leaking. Kept it running - didn't press the accelerator, just let it idle. After about 5 minutes a slower leak and the coolant was low in the reservoir - so I did the same with an additional 1/3 mixed with coolant. I let it idle another 5 min and checked. NO LEAK!
I was still really nervous about these particles going all through my system! I backed the Land Rover down my long driveway so that it was on an incline with the hood higher than the rear (so coolant could properly fill the system,). I was a block from home when coolant just started pouring out. So it was nearly empty. I filled it with coolant and let it burp up any air bubbles - then took it around the block. Immediately, there was a sharper response to the gas pedal, it wasn't stuttering anymore - it was almost chomping at the bit to go forward once I took my foot off the brake at a green light.
I drove it about 10 minutes around my neighborhood up to 35 mph. Back home, fresh piece of cardboard - parked it overnight. Next day - NO LEAK! Still nervous, I tested it again in my neighborhood - everything seems good. Auto repair shops ought to be ashamed for charging people hundreds when this is all they do...
So I ended up using 2/3 bottle and will keep it on hand in case there's another leak. I am concerned about the extra "sealing compound" sitting around and maybe clogging something else - but the description says:
Permanent coolant leak repair - Just shake, pour and go
Mixes with all antifreeze
No draining or flushing
Fixes cracks and leaks in radiator, head gasket, freeze plugs, cylinder heads, heater core, water pump casing and engine blocks
Top international reviews
With the engine off i topped up my coolant again to the correct level, then poured the whole bottle straight into where the coolant goes, then went for a 20 min drive to get everything warmed up so the Kseal fills any potential holes......
500 miles later and the coolant level has not dropped!! Result!! Excellent product, so glad i tried it 5 stars
I guess it's better to replace the problem part if your car is newer and if it makes economic sense but this is a cheap fix for an old car that doesn't owe me anything and so far so good!
You see this product is fundamentally aimed primarily a vehicles with LARGE engines. You absolutely MUST find out what volume of water your engine uses and then use ONLY the recommended amount of the product to suit! - even if it seems tOo small an amount - you must be accurate AND follow the instructions.
If you have a standard MEDIUM engined UK car and you dump the whole lot into your cooling system you are asking for trouble! Use the right amount and if your engines issue is still in the minor stages; you will see good results.
Here's my particular situation.
Nissan xtrail - petrol - when left standing for a few days upon starting would misfire and hesitate for about 10-20 seconds and then work fine. This is indicative of the head gasket on it's way out gradually weeping coolant into the piston chamber.
When you start the car the plug is soaked with water - can't spark and you will get a misfire. As the other piston chambers are fine they get things moving - the water is eventually eliminated out of the exhaust port and the plug dries up sparks and then things carry on as normal.
This was confirmed with low water in the radiator and header tank and using an inspection camera down the plug hole to confirm presence of coolant.
Got new coolant - added the REQUIRED amount of the product - applied as directed and went for a drive as recommended.
RESULT? - No more issues. Coolant levels no longer drop in the header tank and expensive repairs have been offset for a future time (if at all) - as this car has done 150K if I can avoid needing the head gasket being fixed before the vehicle becomes no longer worth running then I have saved a LOT of money.
30 mins later and leak stopped. Done 5k in 2 months including some 500 miles towing and all seems ok. No increase in temperature and no more leaks ore fluid loss.
I added the bottle to a mid warm expansion tank then ran the car static for 30 mins, left for a couple of hours and leak had stopped. I have left it in the expansion tank.
The product resembles baileys so does change the colour of the coolant slightly.
I did a fair bit of research before I bought this and it appears to be the best on the market.
Edit - 6000 miles and still no issues
Product arrived and added to the radiator reservoir as directed. No more topping up the radiator every 4 days. The product works.
If one of the most famous recovery companies has this on their vans. It must be worth keeping a bottle in your car.