Gaskets and/or Sealers?

OK…soon will be re-joining engine parts…and am intrigued with advances in sealants / gasket materials. While I’d love to be a purist and use materials originally engineered for my '65 XKE, I believe engineers back in the day would jump at using some of the newer materials to seal mating surfaces.
So my questions are these:

  1. How do you feel about using just OEM-type gaskets for the engine ?
  2. Do you recommend an OEM gasket and some type of sealant used together ?
  3. How do you feel about Hylomar products, which are used without any gasket ?
    I’m NOT talking about a head gasket here…but all the other attachments, i.e. intake / exhaust / water pump, oil breather, valve covers, etc.
    Appreciate any / all opinions !
    Thanks,
    Harold

I have always used gaskets bought from the usual suppliers.

Other than the head gasket, where I do not use any sealant, I have had great success with using Permatex “The Right Stuff”. It sets to the consistency of a rubber band and is a great barrier against oil leaks. The only problem is that pulling a joint apart after using Right Stuff can be a challenge!

I no longer use it on the cam covers despite the fact it works perfectly, because of difficulty to pull apart. I use the blue stuff on cam covers

Dennis
69 OTS

The Cometic line of gaskets are da bom, and superior to OE style. They do not need sealants.

For the timing chest, a thin schmear of RTV is what I used in place of the paper gasket. If you use paper gaskets, I’d recommend using CopperCoat on them, and ditto for the OE steel head gasket.

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I refreshed my '62 3.8 engine back in 2007 (piston rings and valve guides) and finally managed to achieve zero leaks or drips over the subsequent years.

I used all original gaskets and used Hylomar blue for sealing them and also used that on several troublesome bolt threads such as the upper timing case to cylinder head etc.

On the head gasket, I used the original type pressed steel gasket with Permatex copper gasket spray and also used that on the exhaust manifold to head gaskets. Nothing on the inlet gaskets or spacers.

I also used Indian Head for the water hoses.

I guess one could use Hylomar without a gasket in certain cases but I don’t think on the inlet manifold or water pump. I have used RTV without a gasket on Japanese motorcycle crankcases but they fit a bit better than old Jag engine parts. Nowadays, I would use Yamabond for that.

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For anything that is holding water I use Coppercoat and paper gaskets typically a few coats and it works great on water pumps intake manifolds outlets etc.
valve cover gaskets use hylomar on one side In the right stuff on the other. The right stuff side will hold the gasket to the cover and when you go to remove the cover at some point the hylomar will release.

I forgot about that one: great stuff.

I’m a big believer in the Cometic products. I bought the whole set from Terry’s. The only two that gave me pause were the oil filter housing gasket which just has 3 big holes in it instead of outlining the housing compartments, and the rear sump seal which is a strip of very hard composite. I used original style gaskets in those two places.

But I have them on my cam covers, timing cover, sump, thermostat, breather, intake and exhaust manifolds, and head gasket. A tiny amount of sealant was used in troublesome corners where multiple parts come together, and on the down studs on the head. I also took a suggestion from the engine guy at CJ and beveled the top ends of those down studs to match the inside contours of the head so oil won’t be able to collect there.

So far the only leak I have noticed is a bit from the quick drain fitting on the sump and a few drops from the filter area.

Now Money Pitty’s gunna rust…:grimacing:

Paul
Where do you get the Cometic gaskets. I looked on their site and they had nothing for S1 E Types

@Erica_Moss? Help?

I got the cam cover gaskets, back in 2010.

I’ll add monthly frame and fastener lubrication to my to do list. :wink:

https://www.terrysjag.com/SRCH.html?Search=cometic

Full kits are on page 4

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The stuff originally marketed as “Hylomar” was a blue goo that never hardens. It should not be used without a gasket; it is a gasket dressing, not a gasket maker. It became very popular with the racing crowd for assembly of race cars because it was easy to take apart and clean off – but they did that several times a season. Blue Hylomar won’t stay in place long, but they didn’t need it to.

I believe Hylomar makes other products now, and perhaps some can be used without a gasket. The standard items on this side of the pond are Loctite 518 (for when two machined surfaces come together, no measurable gap) and Permatex Ultra Black (for joints that may not mate up that well so the product needs to fill gaps). With either product used correctly, you could end up with a leak-free Jaguar – which won’t win any concours, the judges know they originally leaked on the showroom floor.

How did you fit the cometic head gasket. I have their .059 which does not have any identification as to “top”. Both sides of the gasket for coolant circulation have only holes whereas the original tin gasket has slots that matched the slots in both the block & head. The coolant holes in the cometic gasket are larger on one side which I am assuming are to be on the exhaust side?
Not to be a bother but can you also expand a bit on bevelling the head down studs at the front. I’m not quite sure what is meant by the inside contours.
Thanking you in advance.

Thanks Much Erica for the link!

Stephan, The one I received looked like the one on the Terry’s site with slots for water. Have you contacted Cometic and sent them a photo of yours?

After threading in the front most studs, the tip would protrude through the open hole (ultimately it simply shouldn’t be an open hole). Oil could collect on the tip and drip down the threads. The inside of my casting slopes downward at the spots where the holes open, so I marked the edge that stuck up the most and removed it and ground down a matching bevel on the stud end, then glued it in and cleaned up the end so the threads were fully sealed and the oil would just flow downward.

Clive - I am a Yamabond 3 believer. BUT if you use with a gasket be prepared for a difficult removal experience. I used it once on the cam covers with Cometic gaskets. The gaskets reluctantly split in half. Hours spent cleaning the surfaces. You’re right though - it didn’t leak.

Its really meant for sealing crankcases together. Timing cover maybe?
Yamaha used to have a version for gaskets. It was #4 or #5???

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After reviewing Terry’s site and seeing the prices for the Cometic gaskets, I am wondering why so many folks have commented on the high cost! Quality is never cheap, but guys, these prices aren’t gonna bankrupt anyone, let along a Jag owner. To me it’s a no brainer to step up. But then again, some folks have said I don’t have a brain!:grimacing:

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Can anyone think of areas where a certain type of gasket maker / gasket sealer SHOULDN’T be used?

On a Jag, no: on my Rover, yes.

The pan rail on the sump uses no gasket, and seals perfectly without anything. That said, I hedge my bets and use CopperCoat.

No sealant or dressing should be used on gortex gaskets. I dunno if you E-type guys even have any gortex gaskets to choose from, but the V12 got the full gasket set shortly after Ford took over. So I guess the SIII guys can probably find a few.

I have also recommended that anyone who has the rear main bearing cap off the V12 should apply a bead of Loctite 518 across the top between the hockey stick grooves and the rope seal grooves. In this case, the sealant must be 518 or something similar, because any sealant with any thickness to it will hold the bearing cap away from seating properly and will cause loose bearing clearances at the rear main. The hockey stick grooves, by contrast, call for something thick and gooey like Ultra Black to be injected after the bearing cap is secured.

When installing the cylinder liners in the V12, I believe Jaguar recommends Hylomar on the shoulders where the liners sit on the block. That’s a typically poor recommendation showing that Jaguar didn’t know much about preventing leaks. That location calls for Loctite 518. And it should go only on the ledge, not all the way down the skirt! When I opened up my '83 it had Permatex sealant all the way down the skirts. Those liners were a bear to get out!