Author Topic: Gasket cement ? What do you use ?  (Read 3594 times)

Offline Viking

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Gasket cement ? What do you use ?
« on: 05.09. 2015 22:12 »
Gasket cement is a world of its own..

I used red hematite gasket compound, but getting it is "rock" hard..

What do you use ?

blue hylomar sealant

I have had great succes with red hermatite. And bad expirence with silicon, and blue hylomar...

I have "played" with bikes for more than 30 years,
But gasket cement sealant is a world of its own

Any trix ?

Online Greybeard

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Re: Gasket cement ? What do you use ?
« Reply #1 on: 05.09. 2015 22:31 »
Blue Hylomar works for me. In my opinion it also looks more professional than Red Hermetite. Getting the jointed surfaces flat first is essential.

Offline morris

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Re: Gasket cement ? What do you use ?
« Reply #2 on: 05.09. 2015 23:08 »
I'm not a strong believer in sealants. To afraid that some excess sealant may come off and block the oilways.
When I took the plunger's engine apart I found the PO used plenty of silicon sealant on every joint... Took me hours to get it all off *problem* *bash*
When putting the engine back together I only used the best quality thickest gaskets I could find and a smear of grease both sides  .
Even after taking the primary cover off a while ago, with only one spare gasket on hand which I broke when taking it out of its packing and by consequence had to use the old one again it's still dry as a bone.
'58 BSA A 10 SA
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Offline muskrat

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Re: Gasket cement ? What do you use ?
« Reply #3 on: 06.09. 2015 05:09 »
I make all (except copper) my own gaskets and use
Silicon is OK if used sparingly. I can use the same gasket multiple times. For copper head and rockerbox gaskets I use
When using silicone be aware that if you see a bead on the outside when the joint if fastened you'll have the same bead on the inside.
Grease works well if the faces are flat and uniform, but again just a smear. It can block nu-pressurized oilways as well. 
'51 A7 plunger, '57 A7SS now A10CR,  '83 CB1100F, 88 FXST .
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Offline Kickaha

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Re: Gasket cement ? What do you use ?
« Reply #4 on: 06.09. 2015 05:56 »
Loctite 518, easy to apply in the syringe it come in and works good enough to stop my BSA leaking, used to use Threebond which is awesome but really sticky stuff and makes a lot more of a mess
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Offline Joolstacho

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Re: Gasket cement ? What do you use ?
« Reply #5 on: 06.09. 2015 08:29 »

Online bsa-bill

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Re: Gasket cement ? What do you use ?
« Reply #6 on: 06.09. 2015 08:33 »
I use the Loctite range of sealants tho to be fair most work well if you avoid bargains (not an area to scimp on )
I used to use an oil soluble one, forget it's name now, theory was/is it only sets in the absence of air so any escaping got dissolved, downside if it's a downside is I would have an extra oil change shortly after it's use
All the best - Bill
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Offline a10gf

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Re: Gasket cement ? What do you use ?
« Reply #7 on: 06.09. 2015 10:04 »
Fix (alu weld) and file back to original any serious surface\edge damage, with large parts (warp\uneven) 'work them' using valve grinding paste on glass surface. Good 'thick enough' gaskets. A drop of blue loctite for carb things, bolts etc (if\when needed).

Avoid any further\new damage by careful and slow cross-tightening of bolts\nuts, especially important if the gaskets are thick.
Never over-tightening. The (perfect ...well, good enough) surface\gasket should do the job, not the extreme force on the bolts\nuts.

And zero stuff that could creep around to the oilways.

Just my opinions.

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Online chaterlea25

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Re: Gasket cement ? What do you use ?
« Reply #8 on: 06.09. 2015 18:04 »
HI All,
blue hylomar sealant +1 , a little goes a long way

I also use "Dirko"

Dirko seems to have become the sealant of choice with most people around here in recent times
I use it on permanent joints,
Unlike "silicone" you can use it where theres petrol /diesel involved
I have seen it seal up leaks in a diesel tank and even seal a crack in a water cooled head
Its a lot easier to separate &remove than the 3bond stuff,
I have also used the high temp type to seal header pipes (when loose) into heads where everything else I tried failed

Works for me

1961 Super Rocket
1963 RGS (ongoing)

Offline Butch (cb)

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Re: Gasket cement ? What do you use ?
« Reply #9 on: 07.09. 2015 07:22 »
Agreed that if you've got good faces and quality gaskets then a light oiling should suffice as well as allowing for easy dis/re assembling next time out; and having a good chance of getting to re-use the gasket. I've never used sealant on my Guzzis and the rocker covers will go at least six 'pulls' without needing to swap to new gaskets.

Otherwise I use Blue Hylomar and also Yamambond, the latter mostly for gasket free surfaces like for joining crankcases. And yeah, sparingly is best.
Warning - observations made by this member have a 93% unreliability rating.

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Offline duTch

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Re: Gasket cement ? What do you use ?
« Reply #10 on: 07.09. 2015 11:07 »

 I always used to use Permatex Aviation goo- with various results and a bit messy but won't get into the oilways; been using 3Bond recently, but with a paper gasket (where applicable), I do the 3Bond on one side and silicon grease on the other which enables the paper gasket to come away clean and reuse easy...fairly much have had the timing cover off a few times, and primary off several- just had to make a new one of that because I burned the old one fixing a leak *eek*
Started building in about 1977/8 a on average '52 A10 -built from bits 'n pieces never resto intended -maybe 'personalised'
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Offline Topdad

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Re: Gasket cement ? What do you use ?
« Reply #11 on: 07.09. 2015 11:22 »
I used to use Hermatite gold for the rocker gaskets ,don't know if still around haven't seen it for years but it worked.
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Online edboy

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Re: Gasket cement ? What do you use ?
« Reply #12 on: 07.09. 2015 21:37 »
i liked hammerite green which went solid and  blocked the rockerbox chisel gaps when it was around. but now i take more care and wellseal is like a glue which seals on its own or between a gasket. a lot of engine builders recommend it for good reason.

Offline terryg

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Re: Gasket cement ? What do you use ?
« Reply #13 on: 08.09. 2015 20:14 »
Used Dirko on a VW Golf sump cover (no gasket) - as recommended.  Went on without difficulty and did the job flawlessly.  Seems to keep well too.

I like Blue Hylomar (and gaskets) for ease of use and cleaning on disassembly.  Paint it on with a fine paint brush and clean with acetone (nail varnish remover).

Have used Wellseal (and gaskets) with excellent results but struggle to clean faces for reassembly.  Put it on with a roller for a very uniform film thickness.

Never had much luck with grease and gaskets but may try again some time.

Used to use silicone sealant (no gaskets) until I got a little more thoughtful.  Have to be desperate to use it now.

Still remember the smell of Red Hermatite - but not keen to use it again.
'57 'SR', '59 SR, '63 RGS

Offline jachenbach

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Re: Gasket cement ? What do you use ?
« Reply #14 on: 09.09. 2015 03:10 »
Depends on what I'm sealing.  For side covers and joining case halves, I have had great success with Yamabond. For rocker covers and other smaller parts I still use Indian Head gasket shellac (by Permatex). Yamabond works great and cleans up easily with lacquer thinner.