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Head Gasket Failure…….Why?

Most head gasket failures are caused by engine overheating. If you’re not sure why your engine overheated, review a short list of the most common causes below. If you’re unfamiliar with automotive mechanical diagnostics contact a licensed mechanic.

Sudden Overheating:
  • Defective Thermostat
  • Defective Electric or Clutch Type Cooling Fan
  • Cooling System Leak
Recurring Overheating:
  • Defective Radiator Cap – not maintaining proper pressure in the cooling system
  • Defective Electric or Clutch Type Cooling Fan
  • Plugged Radiator or Heater Core
  • Sticking Thermostat
  • Cooling System Leak

What is Thermagasket Head and Engine Block Seal?

Thermagasket is a 2-part, Ceramic Fiber, Elemental Carbon and Iron Metallic Alloy compound suspended in a liquid. It works in all aluminum, steel, and cast iron engine blocks.

Is Thermagasket compatible with Anti Freeze / Coolant (Ethylene/Propylene Glycol)?

Thermagasket is not chemically compatible with Antifreeze and therefore cooling system must be drained and flushed before applying Thermagasket.

What is a blown head gasket?

A blown head gasket is a breach in the gasket whose purpose is to form a gas-tight seal between the cylinder head and the engine block. This type of breach typically occurs in cars that have severely overheated. During severe overheating, the head or block warps, pulling away from the gasket. The unsupported gasket fails under the high pressure of combustion or heat from the cooling system. Once the gasket is penetrated, exhaust gasses escape from the cylinders into water cooling ports and often into adjacent oil ports. When this happens, the cooling system malfunctions, causing the engine to overheat.

What are the symptoms of a blown head gasket?

The most visual sign of a blown head gasket is steam visible from the tail pipe after the car is warm. However, many cars with minor damage to the head gasket don’t show any visual indicators. In this case the cooling system must be checked for the presence of exhaust gasses. Another symptom frequently encountered is water in the oil. It appears as a milky white emulsion under the oil cap and on the dipstick.

How does Thermagasket work?

Whenever there is a breach in the head gasket, a cracked head or cracked block, a hot spot develops at the point of the breach. That hot spot can reach temperatures 3 to 4 times that of normal engine operating temperatures. When Thermagasket comes into contact with this superheated area, it instantly forms a perfect high-temperature seal. Once the breach is sealed by Thermagasket’s metallic alloys, heat is deflected away from the patch, eliminating the hot spot and preserving the long term integrity of the repair.

Thermagasket will withstand the extreme heat and pressure fluctuations of any internal combustion engine –Guaranteed!

Will Thermagasket repair my vehicle?

Thermagasket has proven to be effective in up to 94% of all cases, that’s better than 9 out of 10 cars repaired. Of course the success of your repair depends on whether the cause of the initial overheating problem that caused the blown head gasket in the first place has been corrected. If your car is in good running order and the cause of overheating is corrected, Thermagasket is almost certain to repair it. This is why we offer a money back guarantee.

If you do not know why your vehicle overheated, have it checked by a qualified mechanic. If you would like to troubleshoot the problem yourself, follow this link to an excellent Cooling System Overview.



$189.95 Sale Save

Only 0 left in stock

Includes: Cooling System Equalizer Kit & Thermagasket Head & Block Treatment Kit


Since the introduction of the Cadillac Northstar engine they have been plagued with cooling system vapor locking problems and head gasket failure! Which comes first. who knows, we see customers with vehicles that have less than 50,000 miles that have been babied, then we see vehicles that have 150,000 hard driven city miles that have never had a problem ( Until 150,000 miles ) 

We definitely know after assisting in repairing thousands of these vehicles, the failure is a progression.

  • Coolant loss for no apparent reason ( No visible leaks etc )
  • Vehicle starts overheating (Typically starting with sporadic spikes and drops in temperature with the vehicle under a load on the Freeway or going uphill! Then gradually getting worse until it overheats constantly no matter what type of driving )
  • Frustrated you take your beloved Cadillac to the mechanic and the following happens!
  • They correctly diagnose that the cooling system is not circulating correctly! There is no coolant flowing through the radiator.
  • They start replacing parts in hopes of repairing the problem.
  • Replace Thermostat and vehicle still overheats!
  • Replace Water Pump and vehicle still overheats!
  • Finally in the succession of Trial and Error it surely must be the radiator RIGHT! Replace the radiator and it STILL OVERHEATS!

With everything in the cooling system replaced and nothing else to charge you for they diagnose a Blown Head Gasket and tell you that you need a New Engine! At this point with the replacement cost of an engine between $5000.00 and $10,000.00 your faced with spending more than the vehicles worth or selling it for scrap!


Common sense tells us that unless the cooling system is circulating, the vehicle is going to overheat! So if we can get the cooling system circulating ( Eliminate the vapor locking problem ) and stop the overheating, we should be able seal the minor leak in the Head Gasket! ( Most Northstar Head Gasket Leaks are minor, typically there is no water in the oil, no oil in the cooling system, and no white smoke or steam from the exhaust )

Thermagaskets Proprietory Cooling System Equalizer quickly solves the vapor locking issue within minutes. Once installed the cooling system will circulate better than new. Now that the cooling system is functioning correctly we are able to run the Thermagasket Head Gasket Sealer through the system and seal the Head Gasket.

The Northstar is known to run extremely hot, 20 to 25 degrees hotter than your typical V6 or V8 engine. Once the Cooling System Equalizer has been installed and the Head Gasket is sealed, you should see a 3 to 5 degree drop in normal operating temperatures.

The Thermagasket Cooling System Equalizer is proudly made in the U.S.A. from 6066 .058 Wall aluminum with all solid brass hardware, Gates high Temperature Hose and Clamps!

Typical installation time is 10 minutes!

Once purchased you will have access to the best Head Gasket repair Technicians on the planet to assist you with any questions or concerns you may have!

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