Valco Cincinnati 71283 Hylomar Blue Gasket Marker and Thread Sealant Tube with Nozzle - 100 Grams

The good stuff - can't say the "great Stuff"- another brand has already calmed that name, but it is great. Easy to use, never dries in the tube ( in fact it never completely dries ever). Seals gaskets good, but they can can be removed when necessary with out a chisel and hammer! Resistant to most automotive chemicals. I have used this for years on everything from lawnmowers to hot rods. Do it rite the first time, and you don't to worry about globs of silicon coming loose inside the engine or whatever. NOTE: this a sealer / conditioner for gaskets on correct fitting parts. It is not designed to glue things together or make up for damaged or ill fitting parts, or as a substitute for a gasket. Other brands have in the past claimed the the term Hylomar, but they are not the real deal.

Great stuff. I use it on all my air cooled vw builds. Have never had an issue with it. It just seals! End of story!

Originally used this stuff as an aerospace overhaul mechanic when it was made by Rolls-Royce. Had a tube around for about 20 years and finally used it up. Unlike silicone it won't set up in the tube so it's great to have around and keeps. It never hardens and I've used it on multiple low pressure seals that have been leak problems for me. Unlike silicone sealers, if you need to disassemble something you don't have to spend a bunch of time cleaning out the old silicone before reassembly. Also good for keeping gaskets in place during assembly - the hylomar website has good guidance on uses. The one thing to know is that it can be messy if you're not careful- it can tend to get all over things. It's water, gasoline, etc. proof so clean-up can be a problem. I've found that 91% isopropyl alcohol does a great job of removing it, though - much easier than messing with old set-up silicone.

I've been using Hylomar Blue since 1990. It's an incredible product with no equal. This is what should be applied to paper gaskets, NOT SILICON. It also works great for sealing o-ring gaskets such as throttle bodies and intakes, especially ones which are disassembled frequently.

This great stuff, prevents oil leaks.

I use this with gaskets a lot, especially when the gasket is exposed to oil and fluids. Works great and seems to help seal things. Only drawback is the working time is low, it starts to tack up very quickly during application which makes it a little tough to work with. A little on the pricey side for a small tube but it does last a while.

Absolutely great for helping keep a gasket in place for installation. It also does not cure or harden over time so it can resist leaking. Extremely sticky and messy. Also stains blue so wear gloves when handling.

I have use this sealant for years in automotive, marine and aviation applications. The trick I do is to squeeze a small amount of the paste into a small shallow jar (with a lid) and add a small amount of MEK to thin it into a thinner solution. Using an Acid brush the solution can be careful painted on to all 4 surfaces (the 2 MEK CLEANED part faces and both sides of the gasket) and then let it sit for a minute or two while the MEK flashes off. Assemble the parts and torque. It forms a great seal, and shouldn’t ever leak. If you ever separate the parts the gasket will most certainly tear, but you weren’t going to reuse it anyways….. right? A razor blade will scrape the majority of the gasket off and MEK will clean the remaining residue. I reseal the jar so it stays clean and can have more MEK and paste added at a later date. A single tube used this way lasts a long time. Happy motoring