Oil and Oil Filters
Head Gaskets and Valve Covers

Do 'head gasket repair potions' like ThermaGasket work?

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July 15, 2015 8:44PM

Note: This page has been modifying by Woopsgoops, RxAuto,

Jrangel78 since 15 Mar 2008 to today. Some important answers has

been deleted. I am restoring it. These guys are probably related

with RXAuto, the producer of Thermagasket

I didn't use Thermagasket but I talk with Kirk Malley, the owner

of the company, twice. The first time I talked with him, he pushed

me to buy the product saying it is money back guarantee (except

taxes and shipment cost). I made some tests on my car myself to

assess the problem and I have been trying to find out more using

some forum on the Internet. My car is a 4 cylinders Toyota and it

likely has 3 of cylinders that produce immediately exhausted gas

in the cooling system. In the second call, Kirk was trying to

say that people didn't know what was going on. He has always be

nice even if he was selling his product. After I carefully

explained him the tests I did and the result he politely told me "I

cannot help you I am sorry". This is my story. I am pretty sure

that Thermagasket can fix some problems and it is not a scam. If

other products, less expensive could also fix the problem in the

car longer I don't know. $100 for a problem that usually takes more

than $1000 to fix (unless you do yourself) could be a good


The head gasket seals oil ports, cooling ports and the cylinder

compression chambers where the head is mounted onto the engine

block. Problems with blown head gasket include oil loss, coolant

loss and engine power loss due to lost cylinder compression.

This can result in a variety of problems:

1) COOLANT IN THE OIL evidenced by a "milkshake" white frothy

looking goo under the head gasket (look under the oil fill cap (and

under the valve cover through the oil fill port with a flashlight).

sometimes you'll see water or coolant on the dipstick.

2) OIL IN THE COOLANT evidenced by the coolant turning brown

with a slight oil slick look on the water surface (if there's any


3) Leaky radiator or other part of the cooling system; if one or

both of the first two indications are present, then it is likely

that the cylinder pressure is bleeding into the cooling loop. if

this happens then the pressure buildup will cause the weakest point

to rupture.

4) CRACKED or WARPED HEADS. The problem that caused the head

gasket to fail may have caused the heads to either warp or crack.

In this case, there will be more expense than just replacing the

head gasket(s).


head gasket is blown and the only evidence of failure is loss of


I owe a Chrysteler Leberon 1992, the car had some issues

regarding the heating of the engine from past 4-5 months, I

replaced the thermostat then I also checked the cooling pump. My

mechanic had actually removed the thermostat from its system since

it was still overheating. The car worked good for about 2-3 months

but then all of sudden it was again overheating. Mechanic told me

that there is some problem with the radiator of the car, so I

replaced the radiator, along with flushing the cooling system.

which costs me around $350 in all. And now the thing started from

here on, after flushing, they found that the car's head gasket is

gone, there is coolant in the engine oil, which turned it milky in

color and there are smoke clouds coming out from the tail pipe. The

mechanic told me that its better for me to sell it now. But selling

a 1992 leberon in this condition would me not more than $100-200

only!! which I bought for $1500 a year ago. I of course have no

money to spend on it, because repairing the head gasket could be of

at least $600 or more. So, I had decided to try the

Thermagasket on my car. I got to know that they have that

money back guarantee also. So I ordered it for my car.

After getting it, I got to know that the money back guarantee

which they offer is only in case that the car is either scrapped or

donated to someone or the work order is placed for the car in an

authorized service station of repair of the head gaskets which will

at least be of $1200 or more, so i was really worried about it.

Anyways then, I had started following all the instructions given

in the paper which came along with the Thermagasket because

that was the only way for me now. I was running the car at 2000 to

3000 rpm on the final stage of the repair and all of a sudden the

smoke which was coming out from my tail pipe started beginning to

reduce a bit, then after 5-8 min the car noise also changed to

normal and finally the smoke is all gone!! I was really surprised

to see something like that. My car was working normally, I am still

following the aftercare given in the instructions and the car is

working normally till now, It's almost 2 weeks now, I really don't

know that how long it is going to last, but at present it is

working for me. I am pretty much satisfied with the product, for

which I was really not sure in the start. What I think is, if you

are in a position to scrap your car, or if you are really not in a

situation to spend $600-1000 Thermagasket is worth a try,

but still don't trust on the money back guarantee, take it like you

are taking a risk of $150 or so.

Malley of RxAuto Thermagasket: The way the

guarantee works is if your having any issues with the

Thermagasket treatment process, not working you must First

contact technical support and give us the chance to help get the

vehicle repaired. If we cannot help get the vehicle repaired, or

the repair fails the tech support rep will issue a refund


The money back guarantee does work as long as you work with the

technical support (Robert) and all resources have been exhausted.

This product worked for me in my 2000 BMW 528i (2yrs ago) and

re-introduce it again on June 18, 2008 because of a water pump and

auxillary fan failure. Drove car for 30 miles (60 miles roundtrip)

at 80 MPH no overheating or compression buildup in cooling system.

Save me lots of money and time by using the Thermagasket

product again.

It all depends on the damage of the gasket I have used

Thermagasket with no change at all same leak

I just used CRC Copper Block Weld in my 88 Ford Bronco

II. I was losing almost 1 gallon of coolant/day, and my oil had

water in it. I couldn't afford a head gasket, so I tried the CRC

stuff. I followed the instructions on the bottle to the letter, and

now my oil is normal, I'm not losing a drop of coolant, and the

engine runs great!

I didn't know CRC had a product for this (I haven't blown a head

gasket in a vehicle since somewhere around 1966.) Because of the

suggestion here, I researched then tried the (CRC) "K&W

Permanent Metallic Block Seal" and it failed miserably, despite

following the instructions explicitly - it made no difference


BUT (sound of horns blowing and banners flapping), when I

e-mailed CRC and described what had happened, they immediately

offered to replace the product - directly to me. I have no

connection or affiliation with CRC in any way (other than as a

consumer) but I've got to say, that to date - every product of

theirs that I've used (more products over more years than I care to

try to list), I've been, at very least, completely and absolutely

satisfied with. In most instances, I've been incredibly surprised

with the favorable results. It seems as though the can I got was

"very old stock" which isn't too surprising seeing as I bought it

through my local jobber who's 80 mi. from Toronto and their supply

depot is another 40 mi. further from the city (once again, don't

get me wrong. my jobber's prices are great, they've got complete

machine services that can't be beat and their support is amazing?

They just don't have a lot of demand for this type of product.) I'm

going to try it again & despite the failure, I've got another

engine I've already decided that I?m going to use it on too! I was

very relieved to find that their response to my difficulty was an

immediate offer to replace it, because I was very surprised to find

that it didn't work at all and that just doesn't fit with my past

experiences with CRC products.

I know this sounds like a commercial for CRC, and I'm sorry for

that - I'm just trying to relate that I've always had good

experiences with their products.

This leads me to another question though? Does anyone know of

any difference between "K&W Permanent Metallic Block

Seal" and RXauto's "Thermagasket"?

From everything I've been able to find, the only difference is

the price (RXauto's being about 5X.) I'm real interested in this

part too? It's nice to know when others come asking.

We have a 1996 Ford WindStar v6. It overheated really bad, we

had the radiator fixed, but it was still smoking really badly. We

tried 2 products from the auto parts store (not sure what they

were). One was a can one was a white bottle! Both repaired the

problem for about 2-3 weeks, before the smoke returned. My mechanic

said to try Thermagasket, that was the beginning of April,

and the car is still running great!


I used a product called DIKE for 18months, until I could

afford to get it fixed.

Its a plastic like product.

Add a small amount about a week apart until the leak stops.

Then, if it starts up again, add some more.

It is critical that you always know where the leak is and how

much is being leaked.

It will eventually, like the leak in a dam, get bigger until

total failure.

Save up for the repair.


I used k&w block seal. it works great for head gasket

seals and block seals. make sure u follow the directions to the


I repaired my 1994 Saturn which had oil in the water (about a

quart) I used Thermagasket and it worked perfectly. They are

even around for support if you need them. I looked all over the web

for a discussion on this product to see if it worked for others,

but could not find one. I decided if i tried it i would post about

it regardless. Thermagasket worked great for me.

I have a 1994 Pontiac Grand Prix 3.1L V6 145,000 miles.

I HAD a head gasket issue until this weekend, when I used the

Thermagasket Product, I can't speak for the longevity of the

repair yet, but, my initial experience with it has been a positive

experience. As the previous writer stated, the people at

rxauto/Thermagasket answer questions, and have a no pressure

sales approach.

I had to do the quickie treatment because of freezing

temperatures in my area. I flushed the coolant system, changed the

oil and filter, and filled the coolant system with clean water as

directed. It took a little longer than the 15 minutes they stated

for the steam to subside, but after a 50/100 mile drive as

recommend in the directions, the problem seems to be gone.

I used K&W Block seal in a 1990 Dodge Omni

four-cylinder in 2004. It worked from February 11 to March 9 of

that year, then I had the head work done.

I am now facing a similar or worse situation with a '99 Olds

Cutlass, 6-cylinder (with two of everything). I just bought it,

with trading in my previous car, which had run great, (a '93 Buick

Skylark). I have put several cooling system parts on, on advice of

the lot or other mechanics--water pump, thermostat, radiator,

radiator cap, reservoir bottle, catalytic converter, 3 radiator

flush and fills, an oil change, had the transmission checked, and

three cooling system checks.

None of that had helped. I also had it checked by the shop that

had done work prior to my buying it. They'd apparently done an

intake gasket (the cheaper one), but it was still ok according to

the most recent radiator check.

All the checks point to the head gasket. I've tried two types of

Bars Leaks brand: liquid glass that you put into the system after

draining it, (one go-round with help from a mechanic), and the type

that pours straight into the top (two go-rounds myself, based on

website advice to repeat app. once if first didn't hold).

Didn't phase a thing.

Then I tried Bars Leaks Liquid Aluminum and Alum-a-=Seal


No change.

Now, I've been talking with Thermagasket people on phone.

They (he) seem(s) to be a trained mechanic with experience. I told

him my mechanic's own input, which was that those who've tried

sealants, even the elaborate kinds, haven't had any success. And

that the head is probably cracked, not just warped, and that there

is a simultaneous problem with the head gasket.

He answered pretty effectively. He also offered to speak with my

mechanic on the phone, and to walk us through a set of special

procedures he outlined.

I've seen similar procedures listed a Steel Seal's website, but

he said they have you do that, standard, whereas he is only having

me do them, to ensure the maximum benefit, and this would be with

my specific mechanic over the phone if needed.

So, I'm impressed thus far, though I haven't done it yet.

However, one thing, is, how long this will last. They all claim

they'll last forever. This is the thing.

Can you ever have peace of mind? And how ethical can you feel

about trading in the car later, even if the sealant has been hold

for quite some time?

IF I knew more about the "significant" difference between

Thermagasket and Steel Seal, say, or between Bars and

K&W, I could feel better about the later trade-in.

That is, if the seal did hold for a long time. Say, over a year.

Would that be a reasonably long time to think it was a permanent


Most people apparently don't have that much or that lengthy a

success with these, though. ?

What I've wondered about, is if there might be a related

specialty shop, that all they did, was replace head gaskets. You

know, not just a "full service garage" that does everything, but

one that specializes just in doing head gaskets.

If I were going to pick something that there might be a market

for, in this age of aluminum heads, that would be IT.

Because a shop like that, might be able to appreciably lower the

cost of having this particular little expensive job done, by a

couple hundred dollars. There's a sizable market now for this.

Does anyone know of such a place?

I also used K&W metallic permanent block seal.

The head gasket was blown one evening when I was driving home from

work, the water temp gauge went over the top and I had to pull over

to cool down the engine. It took me three hours to get home instead

of half an hour. First, I replaced the thermostat and thought that

it was the overheat problem, but later found out it wasn't the

problem. The coolant looked like a choclate milk and got lots of

white smoke coming out from the exhaust. I googled it and found out

it could be a blown head gasket therefore I checked the engine oil,

which it looked like a thick choclate milk shake. I took out one of

the spark plug and it was completely wet and soaked with the milk

shake. Looking into the spark plug hole, with my flash light, I

noticed there was a thin layer of water in the piston/combustion

chamber, and it looked worst than everything I could think of. So

the bottom line, coolant inside the engine and engine oil inside

the radiator. That was great! I thought the engine was done by then

until I heard about some kind of head gasket sealer such as

Thermagasket and K&W block sealer. I didn't want to wait

and need something fast, so Thermagasket wasn't my option

plus it's on the high side of the dollars. I decided to go to the

local auto part store and bought the K&W metallic block &

head gasket sealer. It cost me only $8 but I didn't think twice to

use it on my 93 Lexus GS300 with has 150k miles on it. I thought

about worst case I would have to donate the car. After two days of

the K&W seal treatment, from flushing the radiator 20 times, to

apply the seal and let it dry...the result was incredible! It fixed

the gasket problem and my engine runs like normal again, spark

plugs are dried, new coolant is flowing clean, no more white smoke

and overheating.

I used Thermagasket in my decade-old Plymouth Voyager,

which had 192,000 miles on the odometer and a mean oil leak from

the rear main seal. (In other words, I had nothing to lose!) The

2.4L motors in those vehicles are notorious for failed head


I followed the instructions exactly and it worked... for about a

year (6,500 miles). It had absolutely no negative impact on the

cooling system. However, its impact on the head gasket was


There is a reason the makers of Thermasgasket guarantee their

product for only 90 days.

If you want the vehicle to be reliable over the long haul, get a

real fix. One that doesn't come in bottles

Maybe for a short, SHORT period of time. Never use long term.

Have a new set of head gaskets put on before you crack a head or

the block.

A lot of people will tell you not to use these liquids and to

get a "real repair" from a mechanic if you want it to last. (I

wonder how many of these people are mechanics...) Well, I followed

their advice and spent $1000 on a head gasket repair. Two years

later, it's leaking again. So if you're worried about the liquids

not being a "permanent" repair, I'd say don't worry about it. The

real repairs aren't always permanent, either, and you can always

dump another can in. If the liquids only last 1 year, you could

make your engine last 100 years with the amount I spent on a

mechanic. I'm going to try one of the liquids this time, maybe the

new Head Gasket Fix by Bar's Leaks that doesn't require you to

flush the coolant first.

If headgaskets were permanent in themselves would we need to

repair them??

YES IT WORKS... to an extent. My 2000 Caddy was

overheating a few years back and thermogasket fixed the problem for

about 15000 miles. I have to reuse thermogasket once a year or so

(and i drive 80 miles a day to work) to 'refix', but the product

does what it says.

SO FAR - SO GOOD! I have a 1991 Toyota previa with 214,000 miles

on it. I had all the classic symptoms of a blown head gasket -

white smoke in the morning, sometimes at an idle, disappearing

coolant, the heater didn't work, horrible smell of burnt coolant

inside the car that was making me sick. It was bad. So I went

online and found the product STEEL SEAL. I watched the video(which

was pretty convincing, the mechanics did not seem to me to be

actors at all). Well , I just put it in this morning (Tuesday,

December 15, 2009) , and I am (almost) beyond words. The

temperature gauge has returned to it's proper operating range and

the car is running great. I drove it for a couple of hours after it

took affect. I kept staring at the temperature gauge every ten

seconds. It didn't budge.

I have all the confidence in the world that it's going to hold

up but I'm positive that the majority of you guys are still

skeptical after only a few hours of service.

For that very reason I am going to give updates every day or so,

because, if this sh*t works - I want the whole world to know about


P.S. If someone sees this exact posting on another site it is

because I copied and pasted it. I don't want anyone to think that I

am some company lackey. As a matter of fact, here is my email if

you want to grill me further - cheerfulinhell@yahoo.com

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