Use Gasket sealant on new gaskets?

[landonshaw]

Thanks for the replies. Tomorrow I will take off the pump a proceed. Talked to the supplier and he said if the gasket is still flexible, don’t use a sealer.
I have a Volvo MD2040. The gasket was purchase last year. Only oil is dripping out, absolutely no water.
The gasket is located between the pump and timing housing. Should be easy to unbolt, CLEAN all surfaces and reassemble. Will let you know later. Thanks

[Compass790]

Originally Posted by Wotname

^^ and it smells nice too

You really need to give up that glue sniffing

[flyingfin]

Since it was a seawater pump, you need to ensure that both metal surfaces are smooth and have no corrosion on the face. Best method is a thick piece of glass to sand the faces smooth with 200 and 400 paper. Then use a thin coating of RTV gasket sealant

[GaryBode]

Everyone, but a few, keep saying "I like" or "I do." Following these people will get you into trouble. Just do what the manufacturer recommends. They recommend it for a reason.

[Wotname]

Originally Posted by GaryBode

Everyone, but a few, keep saying "I like" or "I do." Following these people will get you into trouble. Just do what the manufacturer recommends. They recommend it for a reason.

Haha...
Clearly you haven't worked on older engines where should the manufacturer even actually recommend a product, more often than not, the product has long been discontinued.

And then there are the instances where if there is wear or corrosion, the manufacturers manual says - replace the part. Pretty hard to do when the parts are no longer available.

You approach is fine for when parts are available, money is no object and where mechanics aren't trained in fixing stuff, just replacing stuff.

Now I am not a trained mechanic but holey moley, I had to repair enough engines / mechanical items where the supposedly trained guys have stuffed it up. A boater needs to know how to fix things and listening to what others do regarding gaskets is a good start; just part of seamanship - IMHO of course.

YMMV

[Milko Berben]

In principle I use the factory new gaskets as a gasket can only be compressed once if a joint proves to be difficult it might help to put some sort of sealant on it but ask yourself why? Ask for advice at workshops who deal with this item on day to day basis.
In an emergency you can try and use the old gasket with sealant but there will be no guarantees it will work. just my two cents ;-)

[GaryBode]

Who said anything about parts not being available?

[Emmalina]

weetabix box and grease for me LOL

[timeout2]

The manufacturer might have been some young engineer just out of school with zero practical experience joining mechanical assemblies in a marine environment.

For example bolt torques specs are always listed for dry. I would not reassemble anything without anti seize but the torque reduction is never specified. Anti seize doesn't exist as far as manufacturer is concerned. They're not the ones who remove the rusted water pump.

I keep red RTV and aviation form a gasket handy.

[a64pilot]

You guys that use the Aviation form a gasket, what do you use to clean it off of a part that you remove later?

[model 10]

If installed properly, some paper gaskets can be used over and over. The oil screen or magneto gaskets on some aircraft engines can be used many times for example. In this case, grease is the ticket for long life. I like a wax based grease, it feels better and smells good too.

[Nightcrawler]

Originally Posted by Lepke

Using grease on paper gaskets usually allows you to use them again. It depends on how smooth the surface is. Gasket materials that compress are usually found on less than perfect mating surfaces. A sealer is a little like insurance against leaks, not really necessary.
I've assembled a lot of engines. From radial to diesel. Sometimes with only the gasket and sometimes with only a silicone sealer on racing engines that are disassembled often.
The sealer I use most often is Permatex Aviation Form-A-Gasket. It has a brush applicator and is good for holding a gasket in place while lining everything up. Usually I grease the other side.

+1 on the Aviation product. Let it set up a bit before installing. Also works well on threaded fittings where you just can't seem to get a seal. Impervious to most stuff on boats.

[rbrake]

Old school was thin film of grease to seat the gasket and whistle clean surfaces to start. I never found any reason to change

[davitosan]

Have care with close coupled water pumps. If your leak is water it could be from the pump seal and is deliberate so that when a seal allows some water past it flows from the housing and not into the interior of the engine.

[seatotaler]

On my exhaust gaskets, that connect the exhaust manifold to the rest of the wet exhaust system, the gasket manufacturer which is Osco, included a pink slip of paper saying "gaskets should be installed dry, do not use any gasket sealer, silicone, or other compounds".