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B.J. Kroppe

Hello all -

I ran across this juicy tidbit while browsing through a factory service manual for the AJ16 and V12 engines. Maybe this give some insight as to Jaguar's thinking on the use of sealants. You might logically apply the usages listed here to other parts of the vehicles.
Sealant Usage - AJ16
Hylosil 102 Oil pick-up to transfer housing
Thermostat housing to extension
Thermostat outer housing to inner housing
Timing cover to cylinder block
Transmission adapter to cylinder block
Loctite 501 Oil pump drive-plate bolt
Oil pump front cover to body
Oil pump rear cover to body
Loctite 542 Oil filter threaded insert to housing
Loctite 573 Oil pump transfer housing to cylinder block
Tivoli Kay #5696Exhaust system joints
Sealant Usage - V12
Hylosil 102 Half moon seal to cylinder head
Filler cap o-ring
Vaseline or Silicon 5000 Top of oil filler tube
Dow 111 silicone grease Plug lead to spark plug

Hylosil Sealant - the lowdown

Hello all -

Here is everything I know about Hylosil. I just bought two tubes of it from my local Jaguar dealer.
Informal name: "White silicone" or "White hylosil" or "Hylosil"
Jaguar part number: JLM009710
Jaguar part name:HYLOSIL 777-3C
Price:US$10.50 per tube
Tube size:about 6 fluid ounces or so comes in a hard plastic tube, kind of like a caulking tube. Not like other silicone sealers I've used.
Manufacturer's part name: Hylomar Silicone Sealant, 100 series Gasketing, sealing and bonding compound
Manufacturer:Wm Canning Ltd.
Marston Bentley Division
Cale Lane, Wigan, WN2 1JR, England
tel: 0942 824242 fax: 0942 826653

This is not an advertisement - just passing along the details for you to use. I have not used this stuff yet. The Hylomar name threw me off - I have used the American version of Permatex Hylomar, which is a sticky blue stuff. The white Hylosil that I reference above is not the same stuff. The parts guy at the dealership said this is white. Also, Hylosil has environmental warnings printed all over the tube, related to irritation of the eyes, nose and skin. Blue hylomar has no such warnings, and when I have used it, I have not noticed any strong vapors typical of a silicone sealant, such as blue Permatex (blue RTV).

I intend to put the Hylosil all around my D-shaped seals at the rear of the cam covers, plus the cam cover-cylinder head joint at the rear of the cam cover, on the rear edge and forward, up the two sides for a reasonable distance.

I'm tempted to use this on my front timing cover, see my post on yesterday's pub list. Any advice yea or nay?

Anyone have experience using this stuff?

Now if I could only learn to install my rear main oil seal -- I buggered up the one I have. Then I would really be on a roll..........

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