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BlueDevil Radiator & Block Sealer

BlueDevil Radiator & Block Sealer

BlueDevil Radiator & Block Sealer
$ 29.13

Score By Feature

Based on 101 ratings
Giftable
8.05
Customer service
8.00
Packaging
8.19
Value for money
8.09

OveReview Final Score

How Our Score Is Calculated

Product Description

Leaks originating from radiators and blocks should be fixed permanently.
Radiators made of plastic, aluminum, or metal work well with this product
There are no solids or fibrous materials in this product.
It is easy to use and is safe.
We guarantee it

Questions & Answers

How do you use Blue Devil Radiator Sealer? Do you need to flush your radiators ?

According to the manual, all coolant must be drained and refilled, and the cooling system should be flushed with a flush chemical before using a A friend of mine used the sealer on his engine and all he had to do was drain and thoroughly flush the engine with clear water before applying It was a good year for him. In the case of a product that implies that the product may not perform as intended if you don't use their brand of prep, I am always skeptical. Are there real chemcial reactions taking place without that chemical pretreatment or is it just a gimmick to sell more of the product or is it a way out if they fail to deliver so that they won't be responsible for failing to deliver? I was happy for my friend. My first choice would be to use the Blue Devil sealant on something that needs sealing. If flushing is my first step, I would be a little more thorough.

The blue devil head gasket sealer is similar to this, but how do they differ?

If it's thicker, I'd imagine it's bigger

Are there any steps I should take before I start the engine?

There is a specific statement on the bottle Notice the following A CHEMICAL FLUSH OF DIRTY (OR CIRCULATED) SYSTEMS IS REQUIRED BEFORE INSTALLING THE BLUEDEVIL RADIATOR AND POWER BECASE SEALER" is placed between the blocks of wood.

Would this work on a boat block that has an inboard engine?

can tell you that it worked wonderfully on my Chevrolet block, and I guess it will work just as well on Honda and Toyota blocks. As far as I know, it does not work on plastic radiator components, so you MUST follow the directions to the letter.

Selected User Reviews For BlueDevil Radiator & Block Sealer

After letting it idle for the hour that it says then letting it cool overnight would be best
5/5

On my way out of the house the next morning, I. A rod). The 1936 Pontiac I was using it in had an automatic transmission. In my excitement at seeing the bump in the cast, I was hoping it was just an imperfection in the cast. The mechanic was right, you were losing coolant into your Pumped up radiator with water, filled it up with just water, drilled out inside thermostat and dropped this in. I let it idle for the hour it states to do and Oil level was dead on the stick -) and oil was low. Since then, I have not experienced a single problem. BlueDevil, thanks for your support!.

Claire Powers
Claire Powers
| Jun 29, 2021
The amount I asked may have been too much, but I was not able to accomplish it
3/5

A Honda Civic had a hairline crack in the cylinder wall, so the block and head were milled EXACTLY flat, and the head gasket was replaced as well. Following a call and talking to a technician, I used JB Weld High Temp on the coolant side of the cylinder tube after routing a 1/16 inch slot along the hairline crack and cleaning with acetone I let my repair cure as directed. Once I had a Blue Devil product, I used it exactly as prescribed. During the first two days, it worked. There is no time to waste. There is a more expensive solution than a new short block. An earlier Blue Devil procedure on a Cadillac NorthStar engine successfully repaired a crack entering the water jacket from the engine block's outside.

Cassius Charles
Cassius Charles
| Apr 16, 2021
It is worthless
3/5

It's nothing but a waste of time. It was a direct follow-up to the directions. First, I used Blue Devil radiator flush and it had no effect whatsoever on the leak. In fact, I discovered some nasty crystallized stuff all over the radiator cap - it wasn't good at all. What it did to the inside of my radiator and heater core I will never know. After using this garbage for so long, I regret ever using it.

Sutton BEVAN
Sutton BEVAN
| Jan 27, 2021
I am able to do this! As a result of the engine shifting, my fan blades scraped against the radiator and broke Trying this bottle for the first time, I am pleased with it
5/5

Completely sealed all holes within a short amount of time. I drove the car around town a few times with the missing fan blades, and the car did not break down. Afterward, we drove 30 minutes away and bought a new one.

Eugene Navarro
Eugene Navarro
| May 19, 2021
My entire system went up in smoke
3/5

Nonetheless, it came to an end. My entire system went up in smoke. Although it did stop the leak, it did not completely stop it. That's it for the moment. Because of how much sludge the cooling system produced throughout the entire system, I expect it won't be long before I have to replace the whole thing.

Lionel HODGSON
Lionel HODGSON
| Apr 27, 2021
The five stars are well deserved
5/5

I received this product in a timely manner and am satisfied with it. I recommend it to all.

Legend Russell
Legend Russell
| Dec 26, 2020
If you sold the car, it would be worth more than the car
5/5

However, it only has 96k miles on it so I was hesitant to sell it. If you put pellets in there are brown remnants everywhere but with Blue Devil . It "had" a timing chain cover leak (about $1,200, including chain) and if you put pellets in there are brown remnants everywhere. Radiator fluid in your system is the same color as your system, AND the leak has been sealed. A heater core would be convenient, but Texas is too hot to need one.

Adelyn Reeves
Adelyn Reeves
| Dec 09, 2020
The experiment was successful
5/5

At the bottom of my radiator, I noticed a small leak 2009 Camry with V6 engine. The radiator in my home has not leaked, and I've been monitoring it closely for any signs of a leak. Add a few drops of this coolant to the engine's radiator and run it for 45 minutes with the heater on high and the fan on max. It's that easy!.

Chandler Sanders
Chandler Sanders
| Jul 29, 2021

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