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Fitting one of Danns's header / systems and have read as much as I can on removiing the old header. I'm working in a very tight space and have heard the bottom bolts are a nightmare. I'd like to do this swap myself but would appreciate any experience you guys have.

Cheers
Wozza

Do you mean the bottom nuts on the head flange or the bolts at the cat?

The head flange ones can generally be undone with a socket and then using a spanner depending on the header design. Most you can just take of with an extension and socket.

The ones at the cat usually need a good soaking with wd40 or similar if the system is still stock and hasn't been touched in years.

Buying a small tube of anti-seize and using on the exhaust fasteners is a good idea to make sure you can get them off again if you ever need to. You don't need to do them up stupid tight either.

The best advice I received - from this forum needless to say - about removing exhaust nuts and bolts was to use an impact socket. They fit and do not slip.

Tim

Good sockets, a good ratchet handle (or even better, a good long handled one), a few extensions, and maybe a universal joint.
Use the bits you need to fit the nut.

As for the bolts, give them a good spray of penetrating oil or similar (CRC, WD40, or Wurth Rost-off) the night before.


Just make sure when you start to undo the nuts that the socket head is properly on the nut, if it's on at an angle, or only half on, there's a good chance you may round off the nut.


It really depends on the car, some are almost a full day of swearing and rage, others come loose first time.

The worst one to get off, if it's still there, is the locating plate from the engine/gearbox join to the section of pipe near the bottom of the sweep. Sometimes it's easier to pull out the two engine/gearbox bolts rather than detach the pipe from that plate. It won't hurt anything to have those out while you're doing the job.
As hks_kansei said: good sockets, various lengths of extension shafts and maybe a universal joint.

the other way is take it to the local exhaust guy who has the equipment and the know how. One thing that I learnt a long time ago was to avoid exhausts- bolts and nuts that snap off, knuckles that get damaged, and not being able to get to things and sometimes the need for heat or cutting . Mostly the exhaust guys do it quick and reasonable price. CRC and WD40 are sometimes of no value as exhaust bolts often corrode. Anyway have a go and it might be a doddle.

Thanks guys, really appreciate the feedback. I want to get stuck into the MX myself, but its my only car and I'm wary of stranding it with snapped bolts. Got a good ratchet set and the car will be on axle stands all the way round, but with very limited room actually around the car, if you get my drift. I guess if you don't try, you never know right?!. I'll tackle this next weekend and post back how I go. I'm fitting the whole system so I'm thinking every damn bolt will be coming off.

Is it recommended to change the header gasket at the same time or is it one of those "it depends" questions?

NineElevensies wrote:Is it recommended to change the header gasket at the same time or is it one of those "it depends" questions?

Treat every gasket the same way you would a condom.

Just because you may be able to clean it off and re-use it doesn't mean you ever should.

hks_kansei wrote:

NineElevensies wrote:Is it recommended to change the header gasket at the same time or is it one of those "it depends" questions?

Treat every gasket the same way you would a condom.

Just because you may be able to clean it off and re-use it doesn't mean you ever should.

I'm using that again! (so to speak). Thanks Kansei

Most exhaust header gaskets are steel, so are more easily reused. But I'd agree with replacing any other paper or rubber based gasket, and of course the head gasket.

gslender wrote:Most exhaust header gaskets are steel, so are more easily reused. But I'd agree with replacing any other paper or rubber based gasket, and of course the head gasket.

I've reused the stock steal ones. No problems. Just be careful not to snap any of the bolts - won't be fun.

Alrighty. Might go and invest in some impact sockets and an extension or two. Thanks again everyone, I'll post back next week and hopefully show some pics of one of Dann's finely fabbed exhausts....or ask if anyone knows a good tow-service!

Cheers

I am not sure where removing the head was suggested- surely not required. I have never heard of any engine requiring a head to be removed to take off an exhaust manifold. Take a look at Msngas advice.

Mr Morlock wrote:I am not sure where removing the head was suggested- surely not required. I have never heard of any engine requiring a head to be removed to take off an exhaust manifold. Take a look at Msngas advice.

Removing the original "header", not the cylinder head. Should've titled it "manifold" but I've spent a bit of time in the US so headers are what I call them!.

The other good thing to have on hand is a "rounded nut remover"
It is easy to round a nut when doing this.
Irwin make some awesome nut extractors (get ou of jail) sockets sold at Bunnings. Not too expensive.
They have saved me a few times now.