RTV/Gasket dressings

[dna9656]

So gaskets being what they are...

What gaskets use RTV/Gasket Dressing?

Flip the coin>

What gaskets go on dry?

Why?

[rougeray]

Definition:

"A gasket is a mechanical seal which fills the space between two or more mating surfaces, generally to prevent leakage from or into the joined objects while under compression."

 

Putting sealing agents such as RTV, Permatex, etc are not needed on a gasket if not called for by the mfg. By the above definition the gasket is THE sealing agent. Too many times I have seen a sealing agent added to a gasket not only created a mess but actually was the cause of a leak at the seal point. There are times where a sealing agent can be used to hold a gasket in place while assembling two surfaces but it should be used sparingly. There are products made specifically for that. One of the big problems of using a sealing agent is cleaning the surfaces at a later date. Trying to clean off the previous sealing material from the surfaces can actually damaged the surface so that the OEM gasket would not seal. All of the above applies to o-ring sealing surfaces. Be careful when using a sealing agent between two metal surfaces such as Teflon tape. This should never be used in system where it could break loose and plug an orifice that provides lubrication or say plug an orifice in a pneumatic system.

If the proper gasket or o-ring is installed with no dressing and the sealing surfaces are clean and scratch free and the bolts, nuts, screws are torqued in the proper sequence, the seal will not leak. Just my

[dna9656]

I ran an advert in the classifieds for some parts I needed. I was hesitant to order them from a on-line supplier or the dealer because the shipping costs were too high. The shipping costs were hidden in the cost of the parts, or the parts were priced as though the shipping was included AND there was a shipping charge on top of it as well.

My thinking was I could locate the parts here on the forum and pay a reasonable cost for the parts and shipping.

Well then I went to E-Bay. There I found all but 1 part I needed and the total cost was less than HALF the cost anywhere else and all the parts were NEW. Some parts had free shipping (and the cost of the part was still reasonable) or the shipping was less than the other sources with the cost of the part still being reasonable; most cases WAY less than the on-line or dealer sources.

I pulled the advert. in the classified and feel pretty good about how wisely I spend my parts $$.

Thanks for reading.

[SpencerPJ]

Although I think Rougeray said it perfect, for me, a slight skim of high temp rtv on every gasket keeps the leaks away 100% of the time. Note: slight skim, both sides, and helps hold the gasket.

[djh3]

I will depending on the gasket normaly put a thin coat on the lower surface typicaly to hold the gasket in place. Now if you goop it up your asking for trouble. I can remember way to many times I had to use the wire wheel to remove what was left of cork gaskets off a small block chevy valve cover someone used the ole permatex aviation type sealer on. Now rebuilding a 2 stroke.... yellow dog was your best friend. (3m weather strip adhesive)

[mbrood]

RTV has many uses but is an absolute BEAR to remove and breaks down in the presence of many petrolium products. I like Yamabond #4... thin, resistant, remains flexible and peals off even after repeated heat soaks. You can often peal it from the gasket and reapply after your maintenace is done. Sure saves on gaskets.

 

Permatex had it's uses at the time but it sure had it's drawbacks a few years down the road... made you a real friend with the single edged razor blade ! I bought a car that later needed a new head gasket... I found out why Permatex Red was red... it's permanent. I had a hoist hooked up to the unbolted head and raising it up saw the front wheels come off the ground, resorted to a thin chisel and it finally came loose, but that was after graduating hammer weights a couple times... messed up a perfectly fine head and didn't help the block a bit.

 

Even shadetree mechanics need to keep up with the times and new products.

[greg_in_london]

Yup - Yamaha sells Yamabond for a reason, though I pick one of a range of silicon semi-hardening gasket gloops depending on the application. I've just looked for Yamabond in Ebay and found it, though I've never seen it in a shop. I have used plain gaskets when I haven't been able to find my sealant of choice in the past (or it has set in the tube ), but it has been hit or miss whether it sealed on older engines. Torquing down requires more care, but is well worth it for the reduced leaks. Especially in pre-internet days when replacement gaskets were not readily available ay any sensible price and the old ones had to be re-used.

[csdexter]

This probably doesn't apply to today's motorcycles and technology, but "back in the day", I would just lay the crankcase cover (or part that needed a gasket) on top of a thin sheet of cardboard and tap it a couple times with a soft-faced mallet.

A nice impression of the mating surface would thus remain on the card which I could then clip along the contour with scissors and there you have it: new gasket.

 

Back in the day, the "default paper company" (remember, this was during communist times so we only got one "company" per industry vertical) made A4 student notebooks whose covers were made from the perfect kind of thin card for this application

[mbrood]

Yamabond#4 can also be sourced as Hondabond#4, Suzukibond#4, etc.

 

And yes, standard shadetree for unavailable gaskets is buying a roll of gasket paper, lay it across the needy part and beat with a rubber mallet... leaving the embossed impression and then cutting with scissors, knife, razor... You can buy various thickness as needed and it's WAY cheaper... but YOUR labor will often prove cheaper to your wallet than mass produced purchase... ya got to weigh availability against cost and time.

 

I DO love the idea the Brits have that two machined surfaces will so tightly mate without a gasket or sealer... and they are perfectly correct... up until you run the engine a few times and it goes through heat cycles leaving you typically with one or four small distortions between the two that drip forever. My Nortons were drained, "loosened" and a bead of sealant squeezed in, retorqued and refilled. They would sit in the garage and leave with the same floor condition... no drips. Some called me anal... but not chasing drips is a rather desired thing in my book. You have to understand what you are facing and either surrender or achieve. Many engineers design making highly calculated calculations and assumptions... it's not "nice" to tell them their 'baby' has a problem... take it away and fix it and everybody is happy.

[dna9656]

OK; lots of good information there but nowhere in the Yamaha literature I have can I find a statement about using anything on a gasket. So DOES Yamahas recommend the use of any dressing on their gaskets and if so which ones please?

[csdexter]

The service manual for the RSV mentions Yamabond 4 for the crankcase halves (as the only gasket) and for the cylinder head cover gasket (to keep it in place during assembly, most likely). Nothing for the clutch, alternator and middle gear cover.

[dna9656]

Thanks for the response!

I'm working on a 1st Gen Venture Royale, not a RSV so any info you can provide on a 1st Gen Venture Royale would be appreciated.

[jasonm.]

the only time any sealer should be used is if your surfaces are oxidized. Which is common in aluminum. I found yamabond 4 to be great. And to be re-torqued after one or 2 heat cycles. Everyone has an in/lb torque wrench... 86 in/lb...I think is side cases specs.

[dna9656]

OK; lots of good information there but nowhere in the Yamaha literature I have can I find a statement about using anything on a gasket. So DOES Yamahas recommend the use of any dressing on their gaskets and if so which ones please?

 

 

I did find 2 references in my factory service manual talking about gasket dressings; if I'm not mistaken it recommended Yamabond #4 or a suitable sub. for most gaskets.

[IronMike]

The ONLY thing you should have in the tool box IMHO http://hylomar.com.

 

I've taken a manifold off two years later and it was still flexible. And that was on a 1700 air cooled engine. Didn't even use more to reassemble.

 

Its like spider web in a tube.

[syscrusher]

The ONLY thing you should have in the tool box IMHO http://hylomar.com.

 

I've taken a manifold off two years later and it was still flexible. And that was on a 1700 air cooled engine. Didn't even use more to reassemble.

 

Its like spider web in a tube.

 

Which one?