Rusty manifold nuts

Got a decat downpipe,nuts are seized solid and need heat.i haven't got access to oxy/acet gear.has any one tryed mapp gas as I heard its quite good.

I use Mapp on me plumbing blowtorch. and yes it gets very very hot.

Split them off and replace with brass ones!

have you tried using alot of wd40 to try and free the nuts off?

Tryed wd40 with heat from a standard blow lamp.the nuts are at the stage,age wise of rounding off and risk of snapping the studs if brute force is used.
Cannot get a nut splitter on as they are flanged
Im going to look into access for a grinder to cut upwards on the side of the nut.
Its a job that needs doing as the flexy joint is starting to leak

if you can get a small grinder to the nut, grind 1 side of the flat just to the threads, then use a 6 point socket or spanner to get it off. always use 6 point tools on any exhaust work

spanner, breaker bar and snap them off?

Thor1950 said:

if you can get a small grinder to the nut, grind 1 side of the flat just to the threads, then use a 6 point socket or spanner to get it off. always use 6 point tools on any exhaust work

Click to expand...

that is what im going to try.i have got some 1mm thick cutting discs that should **** through the nuts provided there is enough room to get the grinder in.

dremel with cutting disc fit ?

how about a nut splitter

another forum said:

Tryed wd40 with heat from a standard blow lamp.the nuts are at the stage,age wise of rounding off and risk of snapping the studs if brute force is used.
Cannot get a nut splitter on as they are flanged
Im going to look into access for a grinder to cut upwards on the side of the nut.
Its a job that needs doing as the flexy joint is starting to leak

Click to expand...

chris07 said:

how about a nut splitter

Click to expand...

:doh::smash:

Could try one of these

not sure what they are called

Nut splitter,no use really as the nuts are flanged.

Cold chisel fit on ? If the nuts small enough you might be able to get it to cut through if not how about some of that heat spray or freeze with co2 then hit with chisel

Thanks for all your input,folks
I'm going out to it now to suss the job out,one way or another its got to be done.

I finished up drilling all mine out and replacing them with studding, and fitting RSJ tapered washers on the tops.
Simple solution if all else fails!

Oldseadog said:

I finished up drilling all mine out and replacing them with studding, and fitting RSJ tapered washers on the tops.
Simple solution if all else fails!

Click to expand...

That will be the last resort

Could always just slice it off with grinder to get more room then a 1mm through the stud so the nuts fall off followed by stud extractors as there'll be space then

Well here goes.....,

Attacked from underneath with breaker bar plus extensions,the tell tale squeek,a shot of wd40 and unscrew the studs...happy days and the decat pipe don't half make a difference