Instant Gasket

GrowingLad

GrowingLad

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Morning All,

I'm trying to track down a gasket for the timing gear cover and got talking to my old car supply shop back in the UK for some other parts.

After I got over my surprise that the old boy George is still working in the shop (he was old when I used to buy Chrome polish for the mudguards on my push bike when I were a lad /forums/images/graemlins/smile.gif )

He mentioned about using instant gasket and reckons it's actually better than using a standard gasket.

Could someone let me know their views on instant gasket...would it be okay to use for the timing gear cover?

Many Thanks,

Simon.
 
There are times when it is appropriate and there are times when it is not. It is a silicone so needs to be used in the same way as you would use a silicone for other sealing jobs. If the joint thickness is critical it won't be suitable.

If the surfaces are degreased it will stick 'em together. If you need to be able to break the joint again easily then don't degrease.

Ordinary gasket material is available to enable you to cut your own. Thin card or brown paper is a possibility although not as strong as the proper stuff.

Can't suggest a source in Athens of course but Frost supply a small range of thicknesses by mail order in the UK.
 
Cereal packets work well. Place the casing over the cardboard and trace round. Seal with red Hermatite.

Only use where thickness not critical though.
 
Thanks for all the advice guys.

Quick question, with instant gasket, do you apply it to one piece, offer the pieces up to each other but leave it say 10 minutes for it to set a bit before tightening up the fixing bolts?

Thanks,
Simon.
 
No - with Locktite instant gasket you apply a bead along one of the parts then fit it together right away. You have up to 5 minutes to adjust it. It then takes about 24 hours to cure before being used. The Perkins M50 (for instance) is designed to use it for the camshaft cover as it's the only way the proper clearances can be maintained.

I have also used it recently in conjunction with neoprene gaskets to seal a leaky calorifier.
 
Ducati actually discontinued using engine casing gaskets and recommend using "Ducati Three Bond" which is the best instant gasket I've ever used.
 
A friend of mine had fuel leaking badly from a lift pump on an ancient Watermota and didn't have a tool to undo the bolts. As a bit of a joke I massaged some gasket stuff from my Volvo kit into the joint and within half an hour we had the engine going and it lasted the rest of the cruise. Amazing.
 
It's great stuff, but was told not to buy it by a very wise engineer who told me not to waste my money on it-just use ordinary barthroom sealant. Strangely enough it works!!
 
Three Bond is the trade name for a range of commercial sealants all used by major engine manufacturers, including the Japanese with their own brand packaging. Hence the riduiculous mark up if say purchased from say Cummins, Volvo or Yanmar.

However you can purchase it direct.

However make no mistake this stuff is no bathroom sealant which has no high temp stability and will break down. A tiny bit of silicone in the wrong place can wreck an engine...
 
[ QUOTE ]
-just use ordinary barthroom sealant. Strangely enough it works!!

[/ QUOTE ]
Don't know about b'room sealant but IIRC Loctite instant gasket is spec'd up to 250 deg C - depends what you want to use it for!
 
Threebond 1215 or Hylosil is the best stuff for oily bits. If its an old engine which had a pressed steel cover and a cork gasket, you could run into problems over filling the gap which may have been opened up in the area between the screws caused by a previous owner overtorquing them to cure a weep.

I doubt any instant gasket type sealant will be able to fill a 3-4mm gap effectively for any decent period of time. If its originallly a cork gasket, think again IMHO.
 
My water pump seal dripped on front of my engine. I stripped the pump, took out the old seal and sent my inspector of to shop for another. He came back with seal. We fitted it but outer diameter was slightly less than old. (Old had fallen apart where coil spring sits inside it). We set the seal into Liquid Gold Seal from local car shop ... bolted up. Idea being to see if it worked while waiting for one in post from Perkins agent.
I have new Perkins seal in a packet ready to be fitted, instant gasket seal is still in use 1 year later - not a drip at all.
 
The only health warning that goes with Silicone Instant gasket is not to use too much. I have seen seized car engines with bit of instant gasket that have become detached obviously blocking the oilways in the crank.

That being said, I've used it successfuly loads of times. By preference i'd use a paper gasket with a thin smear of blue Hylomar on either side, even though technically the gasket should seal on its own.

Tim
 
On modern engines all seals should be dry, orther when a silicone is specified.

Wrong grade of silicone justifies the health warning!

Lat year I looked at a Yanmar 6LY 2 which was lierally cut half when a piston cooling nozzle became blocked with a bob of silicone.........15k...........
 
I was surrised when SWMBO's Toyota came back from main dealer after a cambelt service and had lots of sealent around the sump. I mentioned it to another Toyota dealer when I popped in for a part and he confirmed that its now standard practice for sealent to be used on the sump and other areas instead of a preformed gasket.

So must work ok in some circumstanes, those Japs know how to make a car work!

Ants
 
I used some a few weeks ago on the car engine as a replacement inlet manifold gasket. (I'd replaced the blown head gasket with a new one, but forgot to get manifold gaskets.) Worked fine, but, because of the temperature (around freezing) it took much longer than normal (c. 50 mins) to get tacky.
 
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