Exhaust sealing from header into collector?

SuperV8 · Post by **SuperV8** » Tue Sep 07, 2010 12:21 pm

I have a 4 into 1 exhaust with 4 seperate headers feeding into 1 collector. The headers are just a tap fit into the collector. It is before an O2 sensor.

Anyone know what would be best to seal it?

Thanks,
Tom.

Ian Anderson · Post by **Ian Anderson** » Tue Sep 07, 2010 12:33 pm

I've heard grease is the best

It seals well and gives you a chance to get it apart in the future

Sealers etc make it a bugger to get apart

Ian

stevieturbo · Post by **stevieturbo** » Wed Sep 08, 2010 6:29 pm

arent they a tight fit as it is ?

Cant see grease doing anything other than melting and running out.

You can get a copper/silicon RTV which works well, or plain old exhaust paste.

But if the tubes are pushed/pulled tight into the collector, any leaks should be minimal.

How is the collector retained onto the tubes ? IMO springs are useless.

Darkspeed · Post by **Darkspeed** » Wed Sep 08, 2010 7:33 pm

have used high tmp silicone on mine but I dont have any sensors to worry about.

Andrew

stevieturbo wrote:arent they a tight fit as it is ?

Cant see grease doing anything other than melting and running out.

You can get a copper/silicon RTV which works well, or plain old exhaust paste.

But if the tubes are pushed/pulled tight into the collector, any leaks should be minimal.

How is the collector retained onto the tubes ? IMO springs are useless.

mgbv8 · Post by **mgbv8** » Wed Sep 08, 2010 8:16 pm

I used copper grease once. Just once mind

SuperV8 · Post by **SuperV8** » Thu Sep 09, 2010 4:42 pm

Thanks chaps,

Their is a small rubber (gearbox type) mount at the back of the silencer behind the tail pipe which has very little forward/back movement so that is all that holds the silencer on. The header pipes do go into the collector a fair way so it is held rather securly.

Think i'll try the RTV silicone stuff, had a quick google and it does say it should be ok with sensors.

I suppose its would be more to stop air being drawn in and giving false O2 sensor readings, but yes the are a tight fit.

Tom.

bigaldart · Post by **bigaldart** » Thu Sep 09, 2010 8:49 pm

Plain grease works really well, it carbonises really quickly and makes a seal. When I worked in that trade that was all we ever used in the shop.

Alan

stevieturbo · Post by **stevieturbo** » Thu Sep 09, 2010 8:53 pm

the collector should be made in such a way that the ends of the header pipes but against the collector which forms the seal. I take it they arent made like that ?

topcatcustom · Post by **topcatcustom** » Thu Sep 09, 2010 10:06 pm

You might want to consider how you will easily pull it apart if you silicon it up- I'd use copper grease, the worst that can happen is it will run out and you wipe it off.

SuperV8 · Post by **SuperV8** » Thu Sep 09, 2010 11:15 pm

the collector should be made in such a way that the ends of the header pipes but against the collector which forms the seal. I take it they arent made like that ?

Don't know, an exhaust chap made the exhaust for me. I'll have a look.

Good point about taking it apart, if silicon-ed might be a bugger especially as the headers are not movable until the silencer is of!

Tom.

DaveEFI · Post by **DaveEFI** » Fri Sep 10, 2010 8:16 am

SuperV8 wrote:
the collector should be made in such a way that the ends of the header pipes but against the collector which forms the seal. I take it they arent made like that ?
Don't know, an exhaust chap made the exhaust for me. I'll have a look.

Good point about taking it apart, if silicon-ed might be a bugger especially as the headers are not movable until the silencer is of!

Tom.

I tried high temperature silicone between manifold and downpipe on my SD1 and it couldn't take the heat. Fine further downstream.