A Hylomar question.
- Thread starter fiatfan
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Hylosil?
Hylomar might work on Rolls Royce cars, how well I don't know, But On Norton engine cases , it's a big no no, unless you like to see oil dripping.
olympus
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Not to mention Merlin, Griffin and all RR Oilers
Hylosil is a silicone sealant and Hylomar is a jointing compound. I expect Hylosil is ok for a crankcase joint.
fiatfan
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Did a bit of reading; They are used the same way and in the same type of joints as Hylosil, instead of gaskets, so basically the same thing. There are other types of sealants that are used together with gaskets, don´t know the difference between them though.
Me either, but I have been using Threebond for some years now for non gasket joints.
The only other sealant I use is Wellseal, and old style non setting sealant that is useful with gaskets.
Are they the best, well I find them reliable, so I stick with them.
The only issue you can have with silicon based liquid gasket materials is if you use too much, and it is allowed to block oil ways. I pulled one engine I bought apart and it was awash with the stuff, I made a small pile with the amount I pulled out. But used with care there are no real issues with it.
In the end we use what suits us.
DogT
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I used the Blue Hylomar on my crank half's and it didn't work too good, but it was the first time I ever used the stuff. It's got acetone for a solvent, and it's hard as the dickens to put in place. At least for me it was. I wasn't sure how to use it. Hobot recommended it. I think I might have been better off with Wellseal.
i gave up on hylomar use yamabond or permatex #2 aircraft
ashman
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Yammabond, theerbond I have been using it since my first rebuild when converting my 850 to the Featherbed frame back in the early 80s and a few other Norton rebuilds over all these years and have never had one crank case leak or base gasket fail so I stick to it and won't use anything else, well why would I when it works so good, I have use Permatex, Hylomar and other gasket sealants on other parts and have had some gaskets leak over time, there are so many products around these days but I stick to what works for me and not have oil leaks down the road, after 45 years my Norton is still oil tight, but I still get a drip from my drain plug when I let it sit, but I don't use any sealant on it only a copper washer.
Ashley
Ashley
The clear silicone RTV you are referring to cures in air to form a cross-linked silicone polymer. The traditional Hylomar Universal Blue is a thermoplastic polyester urethane polymer that is diluted with and delivered from solvent, but never cures. The solvent evaporates over time leaving behind a flexible film that is considerably lower modulus than the cured RTV silicone.
fiatfan
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I´ve seen "over-use" of orange silicon a couple of times, for example it was plenty on the oil pump gasket in a Norton engine.... must be the worst place to use it. It was also everywhere in both the engine and gearbox on the bike I´m building now.
Fast Eddie
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IMHO good ole Wellseal is perfect for use where joint faces are good. Silicone products are better where surfaces are not good and more 'gap filling' properties are required.
I have used only Wellseal on my Norton engines. The only exception being the Pliobond contact adhesive and copper wire (Jim Schmidt method) that I used on the 920 as I had no choice but to use a copper head gasket, and wanted to minimize the chances of oil seepage as a result.
I have used only Wellseal on my Norton engines. The only exception being the Pliobond contact adhesive and copper wire (Jim Schmidt method) that I used on the 920 as I had no choice but to use a copper head gasket, and wanted to minimize the chances of oil seepage as a result.
fiatfan
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How hard/easy is it to remove?
Fast Eddie
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Wellseal does bond surprisingly over time and is harder to separate than I would have expected from a ‘non setting’ compound to be honest.
Regarding the Pliobond, I dunno yet !
Tornado
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I use blue hylomar on my carb to intake manifold, manifold to head gaskets surfaces. I'm running the heat insulator "gaskets" and don't sandwich them with fiber gaskets. I prefer the no setting blue hylomar as it makes for easier cleanup when needing the R&R things, compared with Yamabond or other setting types. Seems to make a pretty air tight seal.
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