Hylomar - as strange story

[rickb99]

Hmmm, went around town looking for "Hylomar" sealant in anticipation of opening up our MK9 for the first time. After all others, went to NAPA.

I was informed that Permatex was 'phasing out' Hylomar? Hmm really? So he did a search on of the Permatex part number and found 48 tubes in a warehouse somewhere in the mid-west. NOT a NAPA wearhouse but an actual Permatex place. He ordered 3 tubes for me.

Has anybody else heard about this or am I the Dumfooly who's buying the wrong stuff?

Permatex does have a sealant in a can that I think is similar for Hylomar. It say in theory that it's for aviation use in sealing machined surfaces and stays somewhat soft and it's resistant to gas and oil. In reading through the forums I may have to try "STUFF" by Loctite after I throw away 3 tubes of the wrong 'stuff' I order. Duhhh

[SteveG]

I went through the same thing a couple of months ago. I was told by the Permatex sales rep that Hylomar pulled the ol' trademark cease and desist legal angle on them. So Permatex no longer makes a Hylomar look-alike, the do their own thing now that's a gray creamy stuff. I didn't like it so I ordered a tube of real Hylomar(tm) from Dave Bean (www.davebean.com). Now I'm happily smearing blue gel again.

Steve

[Dick R.]

http://www.hylomar.com/

Dick

[Roger Eade]

I am told it was developed in the late 30's early 40's to seal mateing faces on the RR Merlin engine as the machineing was not that good, to stop them leaking, they never really had the same problems with the Packard Merlins (US made) as the machining tolerences were a lot finer (Newer machine tools) but it is still a good product, but for my transaxel I use Hi Temp silicon, I normally put it on one face and let it set, so that there is a nice even smear around the mateing surface, then bang it together the next day, what this does is let you pull it apart several times without having to get your hands messed up with sealer each time you change ratio's.
Roger

[Robert J. Alder]

Sorry you bought up tubes of the Permatex "Hylomar." I've tried their product in the past and as a result over the years had told folks to NOT use the Permatex version. It's not (or wasn't) even a second to the "real" Hylomar made by a Cincinnati firm by the name of VALCO. Permatex may have pulled it for more than patent reasons. I thought theirs was terrible.

Please find and try a tube of VALCO's Hylomar. You might find it a whole 'nuther deal. I love it. Pegasus carries the VALCO, I think. Don't think NAPA does.

[Stan Clayton]

I'm with Roger, in that I use common silicone. You know, the $2-a-tube stuff from Permatex? Smear a thin layer on one surface and let it take a set, then mate the two pieces. Piece of cake! Stan

Edit: it's one-part...not two-part.

[Garey Guzman]

When I was in the LA area, hylomer (the permatex kind) was easy to find. Since moving to TN, no one has ever heard of it.

Stan,
I have never seen ANYONE use regular silicone on a gearbox. Do you do the same thing Roger said, i.e. pull apart and put back together several times between cleaning off the silicone? Which type - Red, Blue, Clear, Copper Plus, etc?

[rickb99]

Okay thanks all. As usual, ask and ye shall learn. So here's my current situation.

1.
I have 3 tubes of some unknown goop on the way from somewhere. All of which I'll find some use for but not the one intended, probably.
2.
I'll run to the store (per Roger and Stan) and buy a two part (or one part) high temperature silcone for $2. If it costs more then 2 dollars, Stan will reemburse me for the difference
3.
I'll order a tube of the for real Hylomar from one of the more common sources just for practice. But I sure like the $2 idea

[Stan Clayton]

I'll run to the store (per Roger and Stan) and buy a two part (or one part) high temperature silcone for $2. If it costs more then 2 dollars, Stan will reemburse me for the difference

Yep, I found it (Permatex 66B) for $2.94 locally by searching "teh intarwebs", but I'm good for the 94-cents. Send me your snail-mail addy and I'll return you a GW...and the stamp is on me!

I have also used Permatex 26B (High-Temp RTV in a red tube) and Permatex Ultra-Blue 77B with equally good (no drip!) results. YMMV.

But no, I don't reuse it...I scrape it off and reapply each time I open the 'box.

Or of course, you can continue to use the $15-a-tube stuff...

Stan

[EYERACE]

Mmmmmmm good!

VALCO Hylomar - tastes just like chicken!

.

.

[rickb99]

Stan, thanks for the choices of what works. I'll look around tomorrow.

If I had known you would owe me 94 cents, I would have hit you up for it at Pacific Raceway a couple of weeks ago. At least save you the 42 cents Now that the total cost has gone over $1 I don't feel right about asking for that refund. The above info was well worth $1.36

[Brian]

Yeah, I know what Hylomar is. I even had a tube once I got as a free sample in England. I have never used Hylomar on a gearbox, and somehow have survived to tell the sad tale...

I used to use "the right stuff" but I switched to whatever silicone seal I happen to have handy. When I was using Orange Hi-Temp instead of exhaust manifold gaskets on one engine I used orange for everything including the gearbox. Now, I use Black because it says it's more oil resistant.

The only leaks are out the side seals if the breather is blocked and out the shift finger because it's an old bearing and it isn't bad enough to put the diaper seal on yet. No leaks anywhere else.

I will say that the 3 minutes it takes to get the old stuff off could be time better spent, but so far I haven't been upset enough to try anything else. Surely not enough to be driving to a different Napa than the one down the street...

Brian

[Stan Clayton]

Hey Rick...I'm good for a 'beverage ticket' at next year's Seattle social!

Thanks for reminding me, Brian, as I too have used the black stuff. Don't have any right now, so don't know its part number, tho. AFAIK, the orange hi-temp stuff Rick refers to comes in a red tube and is marked 26B. Works great! However, most of the time I just use the plain clear silicone (66B). It is not marked for hi-temps nor oil resistance, but it works like a champ. I like it because it cleans off easier than the others and works just as well. The only drips I get are from the shift finger...maybe a couple overnight.

Funny thing, I once saw Arne Loyning's guys using 'aluminum gutter sealant' to seal cam covers on my freshly rebuilt Atlantic engine, so gave that a try on my gearbox for a season (comes in 10-oz tubes from any hardware store...I bought Amerimax "Sealer Mate" GRAY). It too works great, is easy to clean off and costs only a few bucks. But carrying around that huge tube and dispenser was too much for my naturally lazy self, so I switched back to clear silicone (or like Brian, whatever is in the toolbox when I head to the track).

Cheers! Stan

[kea]

I have been selling the real Hylomar, since 1982 (from the UK). Over the years, any repackaged (Permatex, Valco, Autosol) Hylomar, has seemed to been of poor quality. They can re-mix the solvent to Hylomar percentage, and still call it Hylomar sealant, yet it might not work as well.
The use of Hylomar sealant on a Mk8/9, FT or other Hewland gearboxes of that era, should be all that you need when changing gears. To properly use Hylomar, apply to the surface to be sealed then allow the solvent to dry first, before assembly. Hylomar is non-corrosive. It will not fill large gaps (over .010"), is not an adhesive and thus the parts sealed do not need to be pried apart later.
Keith
Averill Racing Stuff,Inc.

[T492]

This from the Hylomar website.........


What is Permatex Hylomar HPF?

Hylomar Ltd in the past has sold a solvent-free version of Universal Blue to Permatex in bulk, which they have repackaged as Permatex Hylomar HPF with our approval. This started at a point when Loctite (the former parent company of Permatex) was Hylomar’s US distributor. Since then Loctite was acquired by Henkel, which sold Permatex in a MBO, which was then acquired by ITW, and Hylomar has set up its own US distribution company. Some Permatex HPF may still be available in retail locations, but it is unclear how long stocks will last….

Vic

[John Robinson II]

Rick,
If you do not want the permatex hylomar, I will buy it from you. I also bought several tubes from both NAPA and the local discount auto and am on my last tube. I have also used the original type and have not had any problems with the permatex stuff. THe thing I liked best about the permatex version was not having to wait the 10 min or so for it to dry.

Also if you know where the balance of the tubes are please let me know as I will try to acquire it.

John

[kea]

Hylomar PL32 (UK), non setting formula, 100 gram tube, $9.95
Keith

[Roux]

If you are using oils like Shock Proof you may consider using no sealant at all for one test day or session to see if you are as lucky as I am. I have no leak at the carrier to case surface and I never use any sealant. This is based on about 12 different times I have assembled this MK9. It really is a pleasure to not have to clean up old sealant when making a gear change. I have yet to try it on the cover surface where I chicken out and use the orange RTV

[Jerry Kehoe]

Having used the original Hylomar for over 30 years with good results including the fact that gear changes usually include wiping the sealant off, which is simple with Hylomar as it is easily removed with brake clean or acetone. I have used the various pretenders to the throne with poor results (permatex,Valco, etc) but have found the original formulation is now made by Wurth UK Ltd, called DP300. It is available from Brit's in Sonoma and probably in their Indianapolis facility. The Sonoma phone number is 707 935 3637. It's not cheap but the results are worth it and a tube lasts quite a long time. If the cost of this is a concern you're in the wrong sport.If you clean the surfaces, brush on a thin coat on the mating surfaces with a flux brush and let set up for a few minutes before putting together. If you do this there is very little chance of any leakage.
My experience with the other variants is they are thin, don't set up, and usually end up not sealing properly.

[rickb99]

Yes, probably. The cost of 6 Cherry rivets is important to me (we are trying to live well below the budget of a Purple Frog).

But, no Permatex Hylomar will ever touch the lips of our gear box. The factory pulled the stuff from the warehouse before my order was filled. Decided to try the Loctite "Stuff" as recommended. Now, being really cheap, I spent $15 as in FIFTEEN dollars for a half length tube of the 'stuff'. That should prove I'm not super cheap all the time.

After it's gone I'll follow Stan and other recommendations and try the precisely priced $2.95 silicone. But I'll have a tube of real Hylomar in the box as a back up

Too bad nobody makes the magic "stuff" you pour into your clutch master cylinder to fix leaks in the slave cylinder. I know, put some silicone in there. That will stop the leak!

[Roland V. Johnson]

If you have the external slave cyl, the fix is to buy one from CNC 619-275-1663. They make good ones and they don't leak anymore.

[rickb99]

No such luck. '89 Reynard FC. Clutch slave is buried deep within the bowels of the beast.

[Modo]

Use Dow Chemical 730 solvent resistant Sealant, expensive but worth it especially if you have a formula vee with leaky push rod tubes, leaky fuel cells (patches will need mechanical pressure on patching material as well) and those dry sump O rings.........since it is expensive I would use it on the lower half of gearbox covers and other silicone on top half.....get rid of that occassional drip from semi resistant sealers such as hylomar and other silicones....keeps for years in fridge...can get at the spruce goose and $10 less somewhere in Kentucky or Tenessee from a supplier...query Dow 730 on web for suppliers....$60 OR $70 a tube but worth it.....my tube is still going 1.5 years later....approved by Bell Hellicopter for fuel line and cell repairs

[Craig Taylor]

Hi, gents,

The beautiful thing about the real Hylomar is that it:

1. Easy to clean up for a gear change. Toluol, Acetone and most brake clean will disolve Hylomar. Silicone is nearly insoluable in any normal solvent.

2. Hylomr remains soft and flexable forever. So if time does not permit complete cleanup, simply aqdd a fresh coating of Hylomar and put it together. Silicone MUST be completely removed, as a dried string of silicone can actually damage the bearing carrer or maincase when the nuts are tightened.

3. Hylomar can actually seal through oil. So if you still have a drizzle of oil, the Hylomar will seal anyway.

Our basic rule is: If it is to be permanant, use silicone seal, preferably aluminum colored as it has the best adhesive qualties. This in most transaxles means the side plates. For temporary sealing, as in bearing carriers, use Hylomar.

We have Hylomar in both the tubes (INV-020001) and 250 ML cans (INV-0200013).

Hope this helps clarify the issue.

Craig

[normv]

I have found Aviation Formagasket. Mfg by Permatex great. It will fill small nics in the case as well . if you are in a rush you can forget about cleaning it off (but is easy to clean when you want to just some solvent), also you just brush it on so you use only a small amouth and the bottle lasts ages, also great for water and oil pumps etc

[bkwanab]

I am told it was developed in the late 30's early 40's to seal mateing faces on the RR Merlin engine as the machineing was not that good, to stop them leaking, they never really had the same problems with the Packard Merlins (US made) as the machining tolerences were a lot finer (Newer machine tools) but it is still a good product, but for my transaxel I use Hi Temp silicon, I normally put it on one face and let it set, so that there is a nice even smear around the mateing surface, then bang it together the next day, what this does is let you pull it apart several times without having to get your hands messed up with sealer each time you change ratio's.
Roger

Who ever told you was wrong. That is just a popular myth here in the US.

Rolls Royce didn't develop Hylomar until the 1960s. It was created to provide a reliable seal between hot sections of their newly developed jet engines. Hylomar seals effectively at both low and very high temperatures.

I first leaned about Hylomar in 1966 when Stuart Turner, the Competitions Manager for Ford Motorsports in the UK, handed me a tube to enable me to replace a leaking cylinder head on the Kent engine in my Rally Anglia at an overnight stop. I had no spare head gasket and Stuart said, "Just use Hylomar. It's terrific" We use it in all the works cars". We did, and finished the rally, helping FoMoCo collect extra points in the British Rally Championship. I did not remove that cylinder head until the season ended months later.

BTW, just remember that the reason Packard were even making Rolls Royce Merlin engines, under a free licence granted to them by Winston Churchill, was because the Packard designed engine was an under performer. It was too heavy and incapable of providing any useful power at operational altitudes. The only place the Packard V12 engines were used was in P40's destined for the USSR for use as ground attack aircraft after Britain cancelled an order for 50 such equipped aircraft as they could not compete with the Hurricane or Spitfire in combat against the ME109

The British built Merlins may have been made using worn tooling by the end of the war but they performed well enough to keep the Luftwaffe at bay until the US eventually decided to join the winning side and use Britain as an unsinkable aircraft carrier for the invasion of NAZI occupied Europe.

The P51 would have been a dog with the Packard V12 installed. The Merlin made the P51 into the star it became. Don't forget, the UK Merlins were used in British Hurricane and Spitfire fighters, the DH Mosquito (which WAS the fastest piston powered aircraft in WWI. Ignore the peons in the P51 caps) as well as the Lancaster four engined bomber, which was the only plane capable of carrying the 20,000lb deep penetration "Block Buster" bomb which was too big even for a SuperFortress to carry.

The Merlin was a great engine and deserves all the credit it can muster. But it did not rely on Hylomar to keep the fluids inside. Knowing the British they probably used some secret formula that incorporated beeswax, hemp string and strawberry jam, or something equally ridiculous.

Finally, I always giggle when I visit an auto parts store and hear people that are confused by the plethora of different 'sealing' compounds. Many stores carry dozens of supposedly different tubes of 'mystery stuff' for goodness knows what. I use Hylomar for every joint, gasket or even just to position parts while assembling them. It is impervious to oil, gasoline and ethanol so you don't even need to absolutely clean mating surfaces before use. Try that with your silicon sealants. I'm confident you could chuck all the tubes in an auto parts store and just use Hylomar. No doubts. No questions.

[TimH]

Knowing the British they probably used some secret formula that incorporated beeswax, hemp string and strawberry jam, or something equally ridiculous

[killerken53]

BTW, just remember that the reason Packard were even making Rolls Royce Merlin engines, under a free licence granted to them by Winston Churchill, was because the Packard designed engine was an under performer. It was too heavy and incapable of providing any useful power at operational altitudes. The only place the Packard V12 engines were used was in P40's destined for the USSR for use as ground attack aircraft after Britain cancelled an order for 50 such equipped aircraft as they could not compete with the Hurricane or Spitfire in combat against the ME109

The P51 would have been a dog with the Packard V12 installed. The Merlin made the P51 into the star it became. Don't forget, the UK Merlins were used in British Hurricane and Spitfire fighters, the DH Mosquito (which WAS the fastest piston powered aircraft in WWI. Ignore the peons in the P51 caps) as well as the Lancaster four engined bomber, which was the only plane capable of carrying the 20,000lb deep penetration "Block Buster" bomb which was too big even for a SuperFortress to carry.

The engine in question was Allison not Packard. They worked OK in P39's for ground attack, but lacked the high altitude power of the Merlins.

[Lynn]

The Allisons also worked just fine in the A-36 ground attack version of the P-51. The A-36 suffered from the same design flaw as the the P-51, the ventral mounted radiators.

[Offcamber1]

If they raced unlimited hydroplanes at 25000 feet the Allison would have been a dismal post-war failure. But it did great until the advent of the turbines.

BTW, Eddie Rickenbacker was mixed up in the original Allison engine project if I recall correctly.

[EricP]

So, on Amazon there is:
Hylomar
Hylomar Advanced Formulation
Hylomar Aerograde
Hylomar Universal Blue

What gives!? I’m guessing “marketing” but I want to get the right stuff...

[DK540]

Check the TDS sheets. Universal Blue is what you want, unless you are building something we don't know about yet. http://www.igsind.com/hylomar/

Hylomar Universal Blue is a polyester urethane based sealant that is non-setting and nonhardening even at high temperatures. The compound is resistant to a wide range of fluids includingall industrial fuels, oils, water and brine, air, turbine and piston engine combustion products, water,water/glycol and methanol mixtures, petroleum and synthetic diester lubricating oils, gasoline andkerosene fluids (Avtur & Avcat) and fluorocarbon refrigerants. Hylomar Universal Blue can be usedto seal joint faces or threaded parts.

Hylomar Advanced Formulation is ideally suited for use as a gasket dressing. It will enhance thesealing capability of all types of gasket and assist with alignment during assembly. The compoundhas excellent rheological properties, combined with resistance to most automotive fluids and manyother chemicals. Being a non-setting and non-hardening compound it also has excellent resistanceto joint vibration, shock and differential thermal expansion.

Hylomar Aero Grade is a highly engineered, polyester-urethane based non-setting and non-hardeninggasketing compound, for use in the aeronautical industry. Hylomar Aerograde was developed inconjunction with Rolls Royce - Aerospace Division for sealing joints in jet turbine engines. HylomarAero Grade can operate at temperatures from approximately –50°C to + 250°C.

Hylomar Aerograde Ultra is a highly engineered, polyester-urethane based non-setting and nonhardening gasketing compound, for use in the aeronautical industry. Hylomar Aerograde Ultra wasdeveloped in response to requests from Rolls Royce - Aerospace Division for a chlorinated solventfree version of Hylomar Aerograde. Aerograde Ultra can operate at temperatures between –50°C andup to + 350°C.

DK