Gasket maker sealant etc pet pieve of mine

hunter townsen · Mar 20, 2015

Over the years I have rebuilt many items from engines , motors (electric}, transmissions , rear ends etc. It never ceases to amaze me how many people use excessive sealants. I am very cautious about the amt of sealant I use. Trust me there can be too much. Case in point, last night I was doing maintenance on a truck I recently purchased. Now at one time someone had put a lot of money in this truck, but not recently. I could go on for hours about this truck. Just a few for instances, I just rebuilt the th 400 auto. I wont go intepo the mickey mouse installation, and repairs on the tranny. someone put a new radiator, all aluminum in recently but when the put the oil cooler lines on the left one of them rubbing on the power steering box, so of course it wore a hole in it. and so on and so on with this truck. Im finally finishing the repairs last night and doing a service on fluids, of course it had a quick change oil change sticker on the window, and found a few in the glove box. And of course the front differential was completely dry, not a drop. so I get to the transfer case, drained it ran a magnet through it all clean. I developed a habit years ago of filtering fluids to see whats in them. Well sure enough there are aluminum shavings in it, or so I thought. First thing this morning I ripped out the tc and tore it open, only to find about a golf ball sized ball wad of silver gasket sealant shavings. not aluminum. Im glad I did because the pump screen was about clogged. The tc was perfect inside. so half a day to tear it out , clean it and reinstall over excessive gasket sealant. As many of you know excessive sealants can wreak havoc. I have my methods of preventing this , I and when possible I immediately disassemble and clean off excess. So for those of you who know sorry about the rant , for those of you who don't , keep this in mind it may save you in the future
thanks for the website
Rob

Ken · Mar 20, 2015

I'm in agreement that two much gasket sealer is used.
I have over the 50 years past work on engines and items needing gaskets been using Permatex on one side only .
Seldom have to go back and fix a leak.
Had a Allis Chalmers WD-45 almost given to me because of leaks of water into the pan . some one had used guessing a tube of silicon sealer trying to stop the leaking. Rebuilt the engine and replacing all the gaskets there is no leaks .
A Farmall "B" engine I just worked on the owner had put in radiator sealer to stop leak to fix a small drip . And sealed the cores so the engine heated into the red . had to remove bottom of radiator and rod the cores to clear the sealer out. Then removed head and around the sleeves. so much junk was blocking the water flow. Ended up a complete engine overhaul just for pin hole leak in the radiator.
Rob thanks for posting this subject maybe some one reading will reduce the sealer and just use a clean surface to repair a leak.
ken

RandyT · Mar 20, 2015

Too much sealant, wrong type of sealant, like silicon caulking, or my best, form a gasket on the head gaskets, and then complain that it blew the head gaskets.

Mace Canute · Mar 20, 2015

How about Loctite on rod and main bearing shells or RTV silicone on carb gaskets?

hunter townsen · Mar 20, 2015

Ha ha seen all that also. the head gasket is one of my favorites lol

LD1 · Mar 20, 2015

Never seen silver gasket sealant.

A pet peeve of mine is using RTV thinking it is a gasket sealant. IF you use a gasket, then use an actual gasket sealant and not RTV. IF you want to use RTV, forget the gasket.

The stuff that comes in a can and is actually gasket sealant is not RTV. And wont do what you describe.

For the price of gaskets, there are only a handful of places I use them. Head gaskets, trans pan, carb, and some of the special thicker formed silicone gaskets like some valve covers and oil pan gaskets.

But pretty much any thin paper-type gasket, I'd rather use RTV.

CalG · Mar 20, 2015

I'm NOT a fan of any of the silly-cone based sealers. The fact that they can usually be rubbed right off most any surface with my thumb has never set well with me. (preparation is everything!)

Pluss, they are so Messy and often used excessively!

But I do like Permatex aviation form-a-gasket for anything that needs to hold oil or water (but not combustion pressure ;-) Thin that material with denatured alcohol so it's not so "bulky" (Don't use RUBBING ALCOHOL, too much water!) The material that gets dried up in the little cans can be reclaimed with alcohol as well. 'Good as new!"

I learned early that paper gaskets work very well on flat milled surfaces. If you expect to take the joint apart during any future routine service, use a light brushing of permatex/ (or insert your favorite sealant here) on one surface only, then stick the gasket on. Lightly coat the other surface with oil or vaseline prior to making up the joint.

If you want a "permanent seal" Soak the paper gasket in hot water for about 5 minutes before assembly of the mating surfaces. The paper fibers swell, with the water, and really bond with the metal. A royal ***** to scrape off when it is time to break the joint, but leak tight until then!.

Cork /Composite gaskets are great for oil pans and other "sheet metal" joints. Oil pans, rocker and lifter covers etc. I like the "one side with permatex" method for those applications.

I haven't really found a solution to the modern automotive cam box cover sealing. There are often multiple sections of rubber bonded sealing segments that butt up to rubber plugs etc. The "corners" are problematic. I tend to fall back to my trusted "Hylomar" gasket adhesive and wait for the inevitable leak from someplace I didn't expect. ;-)

I do use RED high temperature silicone sealant on automotive EXHAUST jounts. It makes it easy to both see any leak (black soot stain), and the joint comes right apart when needed without tearing up the gasket ;-) Can't say I would use the crap on an exhaust manifold however ;-)

In a pinch, If you find yourself needing to seal up two surfaces, and you don't have the gasket, and are not in a position to cut one , The Aviation form-a-gasket can make up the seal on it's own, and neatly! Apply multiple coats of the thinned gasket adhesive with the brush in the can lid. BUT! just daub it on and let the capilary action draw a nice rounded bead all along the sealing edge. No need to brush or wipe, just a wet dab and then retract. A nice smooth bead will develope after just a few repetitions. Let the material set for 2-3 minutes between applications. (About how long it takes to get around many joints)

When there is a nice even bead all around, let the part set for a half hour . Tack free, firm, but compliant. You don't want the material squeezing out as a liquid.
Bring the two halves together, and just hand tighten the fasteners. Let the parts sit another few minutes with thhe gasket sealer between, and getting friendly with it's mate. then tighten it all up . Oh! Make sure all surfaces to be sealed are CLEAN and OIL FREE! Use solvent!!

SPYDERLK · Mar 20, 2015

LD1 said:
Never seen silver gasket sealant.

A pet peeve of mine is using RTV thinking it is a gasket sealant. IF you use a gasket, then use an actual gasket sealant and not RTV. IF you want to use RTV, forget the gasket.

The stuff that comes in a can and is actually gasket sealant is not RTV. And wont do what you describe.

For the price of gaskets, there are only a handful of places I use them. Head gaskets, trans pan, carb, and some of the special thicker formed silicone gaskets like some valve covers and oil pan gaskets.

But pretty much any thin paper-type gasket, I'd rather use RTV.

RTV is a great mold release in the presence of petroleum. Pick where you want the gasket to stay. Lets you reuse a low pressure gasket forever
larry