12 replies to this topic

[fenghuang]

Using "exhaust paste" to seal joints:
Should be used.
Can be used.
Shouldn't be necessary.

Opinions please.

[grck1]

Personally i would use and do use it.

With my 998cc and standard manifold and system, no matter how tight i go it wont seal perfect without it due to wear and tear on the manifold end itself.

 

in the past even with new systems on other cars i have found it necessary to smear a bit in the joints for the best seal plus it aids assembly. 

 

A lot of exhaust pipe is made from flat steel which is bent into a tube then welded so usually is not perfectly circular so paste will help overcome these imperfections

[Stu.]

Using "exhaust paste" to seal joints:
Should be used.
Can be used.
Shouldn't be necessary.

Opinions please.

Not unless you need to.

Yes.

Everything has it's use. I always use it to stop my manifold blowing and it works, so why not.

[KernowCooper]

Be careful and dont over do it as the excess paste hardens and rattles around inside the silencer

[dklawson]

I do use a sealant but I don't use one specifically for exhaust.  I use high-temperature silicone for the joints from the middle of the car back.  In spite of what may be said by other sources, the exhaust temperature from the mid-point back does not get too high for RTV.  The RTV seals gaps between pipes which excludes moisture and makes it possible to separate the pipes again later without rust sticking things together.

[661]

And what is the paste of choice???

[gazza82]

I know this doesn't really apply but you shouldn't if you have a "cat" ... or only used it after the cat ..

[dklawson]

I know this doesn't really apply but you shouldn't if you have a "cat" ... or only used it after the cat ..

 

Very true.  Most CAT replacement procedures mention not using any form of sealant or paste as it can contaminate the catalyst inside.

[maccers]

I use a loctite copper coloured hi temp seal, cant recall the number now but got it from halfords. Works fine on my 1293 supercharged with LCB, use it at all the joints, its flexible and is easy to apply.

[fenghuang]

Loctite 5920 I'm guessing.
http://www.loctite.c...d=8802627420161

[Fossy313]

I use it for my manifold, always have..always will

[maccers]

Loctite 5920 I'm guessing.
http://www.loctite.c...d=8802627420161

 

Yep, thats the stuff.

[dklawson]

I guess I am not that out of touch or off the norm...

 

The bits below are from the web link posted by Fenghaung concerning Loctite 5920.

 

 

(Known as LOCTITE 5920 )

 

LOCTITE SI 5920 for flexible flanges, machined or casted surfaces, high temperature resistant

Technical Data

• Colour: Copper
• Service temperature range: -60°C - +350°C 
• Tensile shear strength: 1.4N/mm²
• Max. gap: 1mm
• Skin over time: 40 min.
• Cure through volume in 24 h: 2.5 mm
• Strength: Low
• Cure method: Moisture (Silicone)

 

And the small print just below the product number on the tube "High Performance RTV".

Edited by dklawson, 24 April 2015 - 04:25 PM.