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Two-Year Test Determines Head Gasket Sealers Can Repair Leaks, Adding Years of Life

Author: ChrisFixTime: 2024-01-06 19:10:00

Table of Contents

Identifying a Leaking Head Gasket

The first step in addressing any potential head gasket issue is confirming you actually have a leak. There are a few telltale signs of a leaking head gasket. We'll explore the most common indicators here.

Understanding exactly how head gaskets function and fail helps identify issues accurately. Head gaskets seal the space between the engine block and cylinder head. This prevents combustion gases from entering the coolant, and coolant from leaking into combustion chambers.

Visible External Coolant Leaks

The cooling system is a closed pressurized system. Any external coolant leaks indicate a breach somewhere in the system. However, external leaks don't necessarily mean the head gasket itself is bad. Thoroughly inspect all hoses, water pump seals, the radiator, etc. for any external coolant leaks.

White Exhaust Smoke

Due to the head gasket separating the combustion chamber and coolant jacket, a breach allows coolant to leak into the cylinders. The coolant burns leaving telltale white exhaust smoke.

Testing Oil for Contamination

Coolant can also leak into the oil through a breached head gasket. This contamination makes the oil appear frothy or milky.

Testing Coolant for Exhaust Bubbles

Similarly, exhaust gases can push through a leaking head gasket into the cooling system. Testing the coolant with a block tester or by examining the coolant overflow tank for exhaust gas bubbles confirms exhaust in the coolant.

Evaluating Cost Effectiveness of Head Gasket Repair Options

Once determining you definitively have a leaking head gasket, decide whether repairing it makes economic sense. Consider the repair costs versus the vehicle's value. Replacing a $100 head gasket in a $5000 collectible car? Sure. $7000 to replace a head gasket in a $1500 beater? Probably not.

Using a head gasket sealer provides a low-cost repair option on an older high mileage vehicle. But understand sealers don't offer a permanent fix. Weigh your specific situation carefully when deciding whether to repair, seal or replace your vehicle after a blown head gasket.

Understanding How Head Gasket Sealers Function

Head gasket sealers contain sodium silicate, aka liquid glass. This seals leaks through a thermal process. The sealer flows into the breach. Intense heat from exhaust gases evaporates the liquid content. This leaves behind a glass seal blocking the leak.

Sealers contain additional components like fibrous material to reinforce seals. OEMs invest heavily in developing effective modern sealers unlike previous sawdust-based old school sealers infamous for ruining engines.

Choosing the Best Head Gasket Sealer Based on Vehicle Specs

With many brands available, choose a sealer matching your vehicle requirements. Critical factors include cure time, active ingredients, thickness and included reinforcements.

Cure time must fall within your engine's normal operating temperature duration before overheating. Thicker sealers with fibrous material provide better seals but increase change of clogging radiators or heater cores.

Sodium silicate remains the critical active ingredient. One sealer uses a copper and fiber matrix relying on pressure rather than high heat to seal which shows promise avoiding high temperature engine operation.

Following Precise Instructions for Head Gasket Sealer Use

Directions vary between sealers for proper application. Carefully follow the exact usage instructions provided. Tips include operating the heater on full blast to avoid clogging that system and allowing thorough cool down cycles to set seals.

Change engine oil after application. This prevents excess sealer material circulating through the oil from causing premature wear on internal components.

Long-Term Testing Confirms Lasting Head Gasket Repair

Despite skepticism about effectiveness, controlled long term testing over 2 years and 10,000 miles confirmed an inexpensive head gasket sealer properly repaired a serious leak in a high mileage vehicle.

The repair endured over a year of extreme seasonal weather fluctuations from below freezing winter temps to above 100F summer heat. The vehicle operated reliably throughout testing until finally the head gasket leak reappeared.

Inspection revealed the head itself had warped over time preventing an enduring seal despite the sealer working exactly as designed. This highlights the importance of confirming root causes before applying sealers.

Conclusion and Key Takeaways from Head Gasket Sealer Trial

When applied properly on an applicable vehicle, inexpensive head gasket sealers can reliably extend the service life of high mileage vehicles. However, understand sealers don't offer a permanent remedy.

Thoroughly verify the precise cause of any apparent head gasket failure before using chemical sealers. And closely follow manufacturer application instructions for best results.


Q: How can I tell if my car has a blown head gasket?
A: Signs include visible coolant leaks, white exhaust smoke, contaminated oil, and exhaust bubbles in the coolant reservoir.

Q: Is it worth using a head gasket sealer?
A: If the repair cost exceeds your vehicle's value, a head gasket sealer can extend its life at a fraction of the cost.

Q: How does a head gasket sealer work?
A: The sodium silicate liquid glass flows to the leak site, then hardens when exposed to high exhaust heat, sealing cracks.