Top 10 Coolant Stop Leaks
for March 2023

MOOZ's editors select recommendations independently. Purchases made through our links may earn us commissions.

1
9.7
SCORE
BlueDevil 00211 Coolant Stop Leak - 16 Ounce

BlueDevil Products BlueDevil Coolant 00211 Stop Leak

by BlueDevil Products
What We like

Easy to use No flushing required

2
9.7
SCORE
ATP AT-205 Re-Seal Stops Leaks, 8 Ounce Bottle

ATP Automotive ATP Re-Seal AT-205 Stops Leaks

by ATP
What We like

Professional strength fast acting resealer, stops leaks fast

3
9.5
SCORE
Bar's Leaks 1186 Liquid Aluminum Stop Leak - 16.9 oz

Bar's Leaks 1186 Aluminum Liquid Stop Leak

by Bar's Leaks
What We like

Special Shipping Information: This item cannot be returned and has additional shipping restrictions

4
9.1
SCORE
K-Seal ST5501 Multi Purpose One Step Permanent Coolant Leak Repair

K-Seal ST5501 Multi Purpose One Permanent Step Coolant Leak Repair

by K-Seal
What We like

If product did not seal head gasket leak, the system might be Over-pressurized, which causes back pressure and doesn't allow the product to reach the problem area, on this page below under Technical Specification is a PDF Guide with instructions to follow to complete the repair successfully

5
8.9
SCORE
Prestone AS145 Radiator Sealer Stop Leak - 11 oz.

Prestone AS145 Radiator Sealer Stop Leak

by Prestone
What We like

Combination of natural and synthetic components provides the ability to seal leaks up to 0.020" x 0.5"

6
8.9
SCORE
Bar's Leaks 1109 Block Seal Liquid Copper Intake and Radiator Stop Leak - 18 oz.

Bar's Leaks 1109 Block Seal Liquid Intake Copper and Radiator Stop Leak

by Bar's Leaks
What We like

Repairs blocks

7
8.9
SCORE
Liqui Moly 20132 Radiator Stop Leak, 0.25 l, 1 Pack

Liqui Moly 20132 Radiator Stop Leak

by Liqui Moly
What We like

For all cooling water and heating systems with and without water filters

8
8.6
SCORE
K-Seal Coolant Leak Repair ST5516 Heavy Duty 16oz, Multi-Purpose Formula for Truck/Tractor Coolant Leaks in The Radiator, Head Gasket, Water Pump Casing & Heater Core, A True Pour & Go -Trade Trusted

K-Seal Coolant Leak Repair Heavy ST5516 Duty 16oz

by K-Seal
What We like

SCIENTIFICALLY TESTED: Safe and effective, our Heavy Duty Coolant stop leak repair seals leaks up to 1/32 of an inch! Once cured, it withstands the high pressure of the combustion chamber, without failing or clogging the cooling system. US Bestseller

9
8.5
SCORE
J-B Weld DS-114 PERM-O-Seal Radiator Stop Leak - 0.7 oz.

J-B Weld DS-114 Radiator PERM-O-Seal Stop Leak

by J-B WELD
What We like

DURABLE FAST FIX: The special compound will quickly seal leaks and will also act as a rust inhibitor and lubricant to internal cooling system parts. It will not clog or harm your cooling system.

10
7.9
SCORE
Bar's Leaks 1194 Radiator Stop Leak Concentrate - 6 oz.

Bar's Leaks 1194 Stop Radiator Leak Concentrate

by Bar's Leaks
What We like

package weight :0.81lbs

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