Paper gasket,RTV or both?

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I usually use RTV on the cover side to keep gasket in place during install.
Some guys prefer gasket only with no sealer.
Some guys prefer RTV only.
Anyone know the correct way?:)
 
I don't use rtv on paper gaskets I use the appropriate sealer such as gaskacinch. You can use rtv alone too with good results. It all depends on who is doing the work. It doesn't matter as long as the installer knows what he is doing. The most important thing is that the sealing surfaces be clean and dry.
 
Originally Posted By: Scott_Tucker
I don't use rtv on paper gaskets I use the appropriate sealer such as gaskacinch. You can use rtv alone too with good results. It all depends on who is doing the work. It doesn't matter as long as the installer knows what he is doing. The most important thing is that the sealing surfaces be clean and dry.


+1 Use one or the other but not both. At least that is what worked best for me over the years.
 
It depends. If it's something like a thermostat gooseneck and someone nicked or scratched the mating surface... getting the old paper gasket off... RTV and the paper gasket will fill that in nicely. I like having the thickness and compressability of a paper gasket. Got one for a hyundai that was a nice thick neoprene type.
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I'm glad after all these years to see o-rings finally used for thermostats a lot more.

Only downside to RTV, IMO, besides dry time is if you get too much down a blind bolt hole it can hydrolock the bolt and keep it from bottoming out properly.
 
I like gorilla snot*** for paper gaskets but just to hold in place.

****Gorilla snot aka 3M weatherstrip adhesive.
 
I've used paper, RTV, and the combination.

When properly prepared, all three work equally well.

When poorly done, leaks are eminent.

'Nuff said.
 
I have found RTV to be very difficult to clean off before re-applying. Absolutely nothing wrong with its sealing capability though.
 
I have had an absolute ton of cars come in leaking coolant because RTV was used to seal something like coolant under pressure so be very careful. The best seal comes from a paper gasket with proper cement or an o-ring. It can be done with RTV, just be very careful. Let it dry before adding coolant and starting the engine.
 
For differential covers, defintately Gasket plus the Black RTV.

Coat the gasket with a thin layer of RTV, wait a few minutes, and then apply while slightly tacky.

Above all, make sure the surface has been wiped clean with a solvent to remove the oil film.

And wait at least 1/2 hour before filling.
 
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If the gasket is silicone (neoprene), i use just the gasket.

If it's a paper gasket, i just use a little RTV to hold it. (assuming both surfaces are even and in good shape)

If the manufacture calls for RTV, then i lay a 1/4" bead all the way around and on both sides of the bolt holes. Place the cover on and hand tighten, wait "at least" a hour and then tighten to spec.

If it's a cork gasket, i throw it away and just use RTV. Unless it requires a gasket for clearance. Then Use a thin layer of RTV on both sides and apply while tacky.
 
If I use a paper gasket I spray it with Permatex Red. That stuff is great, the gasket sticks in place and I've never had it leak. RTV works well in certain instances. For example if a valve cover gasket lip is distorted from someone trying to pry it off and bends it. Or your favorite parts store doesn't have a gasket you need and you're in a bind to get a job done. The trick is to be patient and allow the product to dry before running the engine.
 
Overall, I prefer paper and RTV BUT it depends on the cover. Some covers were designed for RTV ONLY and some were designed for paper. The ones designed for paper don't do as well with RTV only, while the ones for RTV do fine with just RTV of course but OK with paper added (assuming a gasket is available). Neoprene/silicon gaskets are great if they are available for the application.
 
Originally Posted By: dnewton3
I've used paper, RTV, and the combination.

When properly prepared, all three work equally well.

When poorly done, leaks are eminent.

'Nuff said.


This is right.
And you can get RTV off later - it can be very tough with other sealants.
If it leaks, it was not clean, or you did not let it set up before refilling and running it.

And TV is the EASIST to clean of, no
 
Originally Posted By: Scott_Tucker
I don't use rtv on paper gaskets I use the appropriate sealer such as gaskacinch. You can use rtv alone too with good results. It all depends on who is doing the work. It doesn't matter as long as the installer knows what he is doing. The most important thing is that the sealing surfaces be clean and dry.


X2. I use a sealer that is specifically for cut gaskets if I use one.

On my truck I just use Permatex Ultra Black by itself. I have never had any leaks with it.
 
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