Has anybody ever used Hylomar gasket sealant?

[frankd]

A friend of mine suggested that I use Hylomar universal blue non-hardening gasket sealant to cure my alternator cover leak. After looking it up on-line, it looks like it'd be great. Anybody ever use it?

 

http://www.newmantools.com/chemicals/hylomar.htm

 

Frank D.

[FreezyRider]

Looks like it is owned by Permatex now, and I see it is available at Advance Auto. Interesting article, let us know if you try it.

[BigBoyinMS]

Hylomar is good stuff. I couldn't get my intake to seal on the Road Star and fought it for a year. First try with the Hylomar did the job.

 

One suggestion: I've found that it's a little thin. If you'll put it on your cover then let it sit unassembled for about 20 mins some of the solvent will evaporate and it will thicken up a little. Helps it stay where you want it to.

 

Edit: Also available at O'reilly Auto Parts.

Edited January 4, 2012 by BigBoyinMS
Edit: Also available at O'reilly Auto Parts.

[Old Miner]

Hi there.

 

We used it underground on coal cutting machines as gaskets and on gasket faces and I used it over the years on several of my bikes until the tin ran out. Great stuff no problems. They told me at work it was used on Rolls Royce motor engines. (Cant prove that though).

 

Neil.

Old Miner.

[longrider805]

Been a BMW staple since they began making beemers I believe. They probably cook with it it.

[Daveand Barbie]

Hylomar was developed by Continental Aircraft for Rolls Royce. I was first introduced to it by an A&P friend who was a Bultaco rider lime me in the early 70's. I bought a big tube from him that had the aircraft information on it. At that time, it was only available through aircraft suppliers.

 

Hylomar was the only thing we could get to adequately seal the cylinder to case on the large bore Bultaco.

 

Some interesting things I learned from him about the product:

- it is good to let it set for a few minutes to tack up before assembly

- a thin coating is more than adequate to seal a joint

- you can clean Hylomar off any surface, regardless os how long it has been there, with a rag dipped in lacquer thinner..........so need to scrape

- use an acid brush to spread the product, it helps it go on more uniformly and you use less product

 

Currently, there are 2 formulas for Hylomar. If you do a search, you will find them and will find that one is considerably more expensive than the other. The price matches the quality of the product.

 

The Mazda factory manual for the rotary engine specs the use of Hylomar for joining the water seals between the housings. I have this every time I have rebuilt the engine in my race car and have never had a leak. This stuff just works.

[frankd]

Dave,

 

I picked up a tube of the Permatex version of Hylomar at O'Reilys. They didn't have it in stock and had to get it from their warehouse, and it surprised me how old the package looked (I know this isn't a problem). It certainly isn't used by many.

 

I intend on using it to seal my alternator cover. I've put the gasket on twice now dry, and it lasts until the oil gets HOT (long high speed run on a hot day) and then starts leaking--both times in exactly the same place. I was planning on coating both sides of a new gasket with Hylomar. I realize that Hylomar is intended to be used without a gasket, but how do you think it'll work with one?

 

Frank D.

[Squeeze]

Dave,

.... I realize that Hylomar is intended to be used without a gasket, but how do you think it'll work with one?

 

Frank D.

 

That won't be a Problem. Although i for one would only apply it to the Engine Casing Side of the Gasket and let the Gasket set to the Cover. I do this for Years and never had a Leak or needed to replace a Gasket. Did this to my '09 Max when it was brand new and had the Clutch Cover off probably six or seven times after that, still using the original Gasket.

[Daveand Barbie]

Before doing anything, I would carefully examine both mating surfaces to see if there is something that is causing the leak to happen after things get heated up.

 

I would agree that one a gasket, I would only use a sealer on one side of it so to make taking it back apart easier.

 

One thing we have used on gaskets that are on engine cases that were intended to be assembled dry is wheel bearing grease. Take a small amount of the grease and massage it into the gasket, then assemble the cases. The grease softens the gasket and causes a bit of a hydraulic effect to the joint that is somewhat self-leveling.

 

You are going to like the Hylomar. It is great stuff!

[ragtop69gs]

[quote

You are going to like the Hylomar. It is great stuff!

 

I convinced, I'll be adding this to my sealants box. Will it still apply well at sub-freezing temps ?

[frankd]

About 6 weeks ago, I changed the stator cover gasket again. While I had it apart, I inspected the mating surfaces on the cover and the crankcase for imperfections. I did find a small scratch on the bottom of the crankcase, but I don't think it was in the correct possition to be causing my leak. I smoothed it with 200 grit emery paper. Then I cleaned the surfaces with cigarette lighter fluid (Naptha) and applied Hylomar to both surfaces. I put a new gasket on the engine side, and installed the cover, using a torque wrench to tighten the bolts. On the middle gear cover, I put the gasket on dry. The reason I haven't said anything for so long is that I've thought I've had this fixed twice before, but both times getting the motor hot in traffic started it leaking again. Well, I've got about 4,000 miles on it now, including traveling in 95 degree weather and also getting stuck in Atlanta traffic and having the fan run quite a bit. I just got on my hands and knees and checked.....the engine is dry---the leak appears to be fixed.