Is liquid gasket any good?

OpenToSuggestions · 13 Jun 2013 at 23:12

Hey all.
I bought a custom backbox and stainless steel decat. The decat came already bolted on the exhaust.
When putting the decat onto the manifold, can I get away with using a liquid gasket? I have not got a proper one, but will buy one if required.
Matt

rodenal · 13 Jun 2013 at 23:14

I take it you're talking about proper exhaust putty (firegum or whatever) and not the instant gasket that's intended for ancilaries / valve cover gaskets etc? Otherwise it won't work.

Tbh I usually use putty and the right gasket, you will probably get away with it though depending on the type of joint

OpenToSuggestions · 13 Jun 2013 at 23:16

Yeah I mean exhaust stuff

.

I have not got the gasket, but wanted to do the job this weekend but will wait if I need to do so. It is a standard flanged exhaust mating face, with a bolt either side of the main pipe.

rodenal · 13 Jun 2013 at 23:17

Should be fine

OpenToSuggestions · 13 Jun 2013 at 23:19

rodenal said:
Should be fine

Do Halfords sell a product suitable for this? If so do you know what it is called?

.

rodenal · 13 Jun 2013 at 23:29

Firegum is the most popular one I think. Halfords or any small motor factor type shop.

Wear gloves it's not really stuff you want on your hands - don't let it sit for a long time after you've applied it either it's the heat that sets it (instructions will be clear)

Matt-Page · 13 Jun 2013 at 23:40

Make sure both surfaces are clean and then apply an even amount to both sides. Clamp them together as evently as possible. Once bolted up and secure. Start the engine and let it idle. Don't drive or rev it. Leave it idling for 10-15 mins so the exhaust heats up and dries the firegum. Should be fine :-)

Vigoro · 14 Jun 2013 at 00:21

Not got a local car parts place that can order a gasket? They should only cost a couple of quid max, and most places should be able to get them in the same day if you phone em in the morning.

nutcase · 14 Jun 2013 at 08:42

Just use cheap silicone sealant. Cheaper the better - ie. no anti mould stuff or anything. Much better than gun gum etc.

Amps · 14 Jun 2013 at 08:45

nutcase_1uk said:
Just use cheap silicone sealant. Cheaper the better - ie. no anti mould stuff or anything. Much better than gun gum etc.

I tried this as a temporary fix on my motorbike exhaust. It resulted in the silicone going on fire (smoking) once the bike got up to temperature. Would not recommend.

pastymuncher · 14 Jun 2013 at 08:45

Do the job properly and get the correct gasket for it or you will probably end up doing it again. Liquid gasket on a exhaust manifold is not a good idea.

*Moangroan* · 14 Jun 2013 at 12:28

pastymuncher said:
Do the job properly and get the correct gasket for it or you will probably end up doing it again. Liquid gasket on a exhaust manifold is not a good idea.

this

Its should be cheap from a motorfactors.......if you dont use a gasket it may blow some gun gum out later and u will have to take it all off.....there is loads of vibration and pressure there.

OpenToSuggestions · 3 Jul 2013 at 21:03

Used a proper gasket - Cost me £1.50!

Had to get a garage to fit it as the bolts were rusted on. I tugged as hard as I could (snigger) with the spanners but no luck.

Sounds good though and definately a bit quicker without the cat.

Dogbreath · 3 Jul 2013 at 22:35

nutcase_1uk said:
Just use cheap silicone sealant. Cheaper the better - ie. no anti mould stuff or anything. Much better than gun gum etc.

Bit of a thread revival, but silicone sealant on exhausts (especially on a decat pipe or manifold flange) is a good way to kill oxygen sensors.

nutcase · 4 Jul 2013 at 08:10

Interesting - presumably if it's downstream of any sensors then not an issue?

Never had a car with an O2 sensor that I've actually bothered with an exhaust )