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The ST5501 Multi Purpose 1 Step Permanent Coolant Leak is a compact, easy-to-use additive designed to permanently seal coolant leaks in all vehicle cooling systems. Engineered for fast, reliable performance, it offers a professional-grade solution that saves time and prevents costly repairs.





| ASIN | B001QT9KO6 |
| Best Sellers Rank | #1,796 in Automotive ( See Top 100 in Automotive ) #1 in Cooling System Additives |
| Brand | K-Seal |
| Color | BLUE |
| Customer Reviews | 4.3 4.3 out of 5 stars (12,835) |
| Date First Available | January 26, 2009 |
| Global Trade Identification Number | 05060002968017 |
| Is Discontinued By Manufacturer | No |
| Item Form | Liquid |
| Item Weight | 9.2 ounces |
| Item dimensions L x W x H | 3.5 x 1.5 x 4.5 inches |
| Item model number | ST5501 |
| Manufacturer | Solv-Tec |
| Manufacturer Part Number | ST5501 |
| Material | Plastic |
| Model | K-Seal ST5501 Multi Purpose One Step Permanent Coolant Leak Repair |
| Number of Items | 1 |
| Position | Inner |
| Product Dimensions | 3.5 x 1.5 x 4.5 inches |
| Style | Compact |
| UPC | 367157659506 812646010004 |
| Unit Count | 1.0 Count |
| Water Resistance Level | Waterproof |
R**I
Superb As described
I had a leak wasn't detectable, it drove me crazy, no white smoke and no sign of leak, every week i had to top up around 200ml coolant, even at garage wasn't found, and this little magic did stop the leak almsot a month and half no issue till end of July ++ Edit by August beginning Oil mixed with coolant , looks heat exchanger inner issue hop not followed by usage of this item!++ Edit Sep August End coolant pump stopped working, and thermostat and leak from Radiator after heat start to go up, unsure if system clogged, leak was mostly by Radiator damage but not visible because evaporated due engine heat and air flaw!
M**D
Excellent product. Works really well as advertised.
Excellent product. Worked wonders with my 2003 Volvo s60 with 261000 kms on the odometer. The engine head gasket had blown up causing water loss. K-seal sealed it in 20 minutes. After applying the fix I drove it for almost 100 kilometers and no water loss at all. Though I have to see how long it lasts. Six months since I used it and the car still runs great without issues.
D**S
Leakage killer
It killed my coolant leakage
A**R
Good
Been 1 week, leak reduced. Hope will solve on long run too.
F**T
It is literally working.
My car's engine water was needed to get refilled once in a week(I drive the car everyday almost 15km). I fed up and finally bought this product. It was my last chance before visiting the garage. I have tried this sealer with my car and amazingly it worked. I saved 1000$ by paying only 50$. Thanks.
R**.
It will ruin your car
It messed up something with my car, within 2 days my radiator fan and cooling fan resistor was blown out Never add something to your car system it will eventually ruin the car I ordered on the basis of rating so dont get fooled with product ratings
A**D
Real leak sealer 🏁
It solve the problem, leak stop permanently, good product 👍
A**N
ineffective on my car's leak
didnt fix the leak
C**N
Seems to stop leaking from plastic header of the radiator.
M**N
Fungerade mycket bra. Jag är nöjd. Bara att skaka burke jättenoga först. Sen hel i allt
I**U
efficace dès la 1ere utilisation. plus de problemes de fuite depuis. un miracle ? pour le prix cela vaut le coup de l'essayer plutot que d'engager de gros frais pour les réparations.
C**N
Utilizzato con molto scetticismo un mese fa su di una fiat punto che consumava da tempo acqua e a freddo andava a tre cilindri perché la candelasi bagnava.. Ha funzionato alla perfezione,il primo giorno ha smesso di andare a "tre" e nel giro di pochi il consumo di acqua si è fermato definitivamente. Al momento altamente consigliato.
V**N
I had observed oil leak signs in the coolant, Probably faulty oil cooler gasket or Engine head gasket. I poured this liquid to the radiator and drove my Thar crde for almost 30minutes. Next day had gone for 400kms drive as well. No further oil leakage. Coolant looks clean now. Its been almost 3 weeks now. Oil mixing with coolant has stopped perfectly.
Trustpilot
3 days ago
1 month ago