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Permatex 81878 Ultra Copper Maximum Temperature RTV Silicone Gasket Maker, 3 oz. Tube Permatex 81878 Ultra Copper Maximum Temperature RTV Silicone Gasket Maker, 3 oz. Tube

Permatex 81878 Ultra Copper Maximum Temperature RTV Silicone Gasket Maker, 3 oz. Tube

Permatex 81878 Ultra Copper Maximum Temperature RTV Silicone Gasket Maker, 3 oz. Tube Permatex 81878 Ultra Copper Maximum Temperature RTV Silicone Gasket Maker, 3 oz. Tube
$ 4.83

Score By Feature

Based on 2,635 ratings
Easy to use
9.70
Adhesion
9.68
Value for money
9.53

OveReview Final Score

How Our Score Is Calculated

Product Description

By entering your model number, you can make sure that this fits.
High-temperature RTV silicone gasket that is the most advanced on the market.
Three times the oil resistance of traditional silicones, and eight times the flexibility of cut gaskets
Sensor-safe, low-odor, non-corrosive, and adhesion-enhancing
Temperatures fluctuate between -75 and 700 degrees Fahrenheit.
Exhaust manifolds/headers, valve covers, oil pans, timing covers, water pumps, thermostat housings are just a few examples of possible applications.

Questions & Answers

Is it possible to use this to improve the seal on a valve cover gasket?

Yes. It outperforms OEM gaskets in terms of conforming to warpage, dents, dings, and other imperfections. OEM gaskets are designed for brand new, perfect valve covers with no flaws, whereas aftermarket gaskets are designed for used valve covers. It can withstand temperatures of up to 700 degrees Fahrenheit.

Can I use this to connect my gas furnace's radiator tubes to a heat exchanger? It doesn't have any gaskets anymore. ?

Hello, and welcome! Because I'm not familiar with this application, I can only say that Ultra Copper is great for sealing liquid coolant surfaces in truck and auto repairs. This product can withstand temperatures of up to 800 degrees Fahrenheit and pressures of up to 15 pounds per square inch. It's still a pliable sealing silicone "glue," but it won't harden like epoxy. Look elsewhere if you're looking for a hastening sealer. You're good to go if it's for a flange or any other flat, secure surface. If you're looking for a product that doesn't contain acetic acid, this is it.

Is it okay if I apply this to the outside of the exhaust manifold leak like caulk, or does it have to go between the parts? Is there a V8 in the 2004 Ford F150?

There is too much pressure and heat to use caulk or rtv at this time. Even muffler cement is ineffective. It's possible that the problem was caused by a lean fuel mixture to begin with. Exhaust bolts rust solid due to heat erosion; to remove them, use the appropriate number of points on the socket(6 sided bolt-- Copper metal exhaust gaskets (six-sided socket) are a good choice. Mr. Gasket is a well-known name in the gasket industry.

Is it possible to use this product to seal a number of non-absorbent surfaces? Instead of using standard gasketing material, why not use the moving parts of a wood burning stove?

Yes, it can withstand extremely hot conditions. I've used it to replace the gaskets on my wood stove and to keep the glass in the door from shattering. This is a fantastic product, but make sure you properly seal the tube because it will easily harden.

Selected User Reviews For Permatex 81878 Ultra Copper Maximum Temperature RTV Silicone Gasket Maker, 3 oz. Tube

It'll work if you do it the right way
5/5

Ultra Copper is used as a gasket on its own, not in conjunction with a paper or rubber gasket. In addition to the Ultra Copper, I do not use a gasket. I DO NOT FOLLOW INSTRUCTIONS WHEN I APPLY! I make certain that EVERY SURFACES is clean and grease-free. free. Then I applied a coat directly to the surface of the part to be attached (not the receiving surface) with my finger. I wait for the first coat to dry before adding a second. I re-used it after it had dried completely. affix the component to the surface that will be receiving it. I've had no drips, runs, or leaks as a result of using Ultra Copper on oil pans. br>br>When using Ultra Copper on oil pans, I apply it to the oil pan itself. I apply the Ultra Copper to the valve cover itself when using it on valve covers. I always use Ultra Copper on the part itself rather than the receiving surface. BEWARE! br>br> This is the method I've been using for years with no issues. It keeps gasket material from squeezing or compressing into (valve chambers, oil chambers, and so on). This is NOT a recommendation due to liability concerns; rather, it is a description of how I use it. When using Ultra Copper, you should rely on your own judgment.

Aya Webster
Aya Webster
| Sep 07, 2021
When dealing with a leaky exhaust system, this is a must-have item
5/5

After using an angle grinder to separate a mid pipe exhaust from a catalytic converter, I applied this RTV to a metallic gasket as a second line of defense against exhaust leaks. After applying this, I waited 20 to 30 minutes before starting the car. After four days of driving and no leaks, the vehicle is safe to drive. The inner border/ring of the gasket had a thin 1/8" streak applied to it, i. e. I didn't use my hand to smear it across the gasket.

Arturo Steele
Arturo Steele
| Feb 23, 2021
Very useful for making heating element boots for 3D printers
5/5

I used it to make "silicone boots" for my monoprice maker ultimate 3d printer, and it seems to work pretty well in comparison to mixing my own strange silicone solution. I coated the insides of 1bigpig's thing printed in black PLA with costco dish soap, squeezed enough to fill between 2/5 and 1/2 of the container, and then squeezed some more. I was able to fit a usable silicone boot onto my printer after a day. I must have made at least 6 before stopping, and I had only gone through about two-thirds of the tube. br>br>The only drawback I can think of is that it's a pain to get off your hands or any other surfaces it comes into contact with, and it stains copper, so be careful. It cleans your hands, but it is time consuming. However, it appears to be able to withstand my printing temperatures of 260°C without issue, so I'm happy.

Landry Cantrell
Landry Cantrell
| May 07, 2021
Cap that is both cheap and useless
3/5

This product is great, but the caps are so flimsy that they crack after only a few uses. As a result, it's a one-of-a-kind tube. Purchase made on a whim. It's always dried up when I need to use it! Fix this!.

Legacy Kaufman
Legacy Kaufman
| Jun 06, 2021
After 40,000 miles, there is no longer any exhaust leak
5/5

Over a year and 40,000 miles ago, I used this on an exhaust flange that I couldn't get to seal, and it's still holding. I was skeptical about how long it would last, but I put it to the test and it's still going strong.

Alice Duran
Alice Duran
| Jun 26, 2021
I think this is the best I've come across so far
4/5

So I used this to seal up the leaking areas of my offset smoker; it worked pretty well and hasn't shrunk much, but I did use a lot just in case. It has a much higher heat resistance than the red silicone sealant that everyone else uses, and the areas that were sealed with it looked great after they were painted over. I sealed the smoke stack to the smoke chamber, the nuts and bolts, and the firebox connection to the smoking chamber; the only place where this didn't hold up or last was in the firebox lid, where all the heat was hitting and exceeding the silicone's temperature limits. br>I strongly advise purchasing at least two tubes and gently massaging them before opening them to ensure that everything is still mixed together. br>I've read that some people are having trouble with chemical separation in the tubes, and that it's difficult or blows out the tube. If this is the case, try squeezing from the bottom up while rolling the tube up.

Alia McFarland
Alia McFarland
| Jun 14, 2021
It's really good! When I needed to replace rusted flange bolts and rusty gaskets, this stuff did the job of filling the gaps around my muffler flange gasket that didn't seal properly
5/5

br>br>If you follow the directions and let it cure for 24 hours, you should be fine. The lower ratings indicate that people did not adhere to the instructions or did not use a thick enough bead.

Gunner Lucas
Gunner Lucas
| Jun 22, 2021
The silicone boots for 3D printers are ideal
5/5

This was my first attempt at making something with silicone. I was a little intimidated, but I figured that a tube of one-time use tape would suffice. I used Thingiverse to print a mold for my Geeetech A20M OG hotend and squeezed some of this paste into it. The mold was ready after about a day (with some light heating in between). I got the best results when I used a paintbrush to "paint" some dish soap all over the mold. The cured product is flexible and has been exposed to temperatures of 200°F for several hours. I am pleased with the temperature of 240 degrees Celsius.

Ben CONNOR
Ben CONNOR
| Jun 29, 2021

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