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MG MGF Technical - Exhaust Fitting for Dummies

I'm new to this "hands-on" stuff - never having done much more than fill up and drive before. But i've been encouraged by this BBS to have a go and i'm about to fit an exhaust.
That's my first problem.
I've checked the FAQ and it looks pretty straight forward but does anyone have any pictures of the nitty-gritty actually being done - where exactly to jack, where to put stands, is it best to remove the rear bumber etc?
I'll be honest, when someone says "use the subframe longitudinal members" I'm a bit lost - but show me a picture and I'll be right with you....
Many thanks
John Philpott

I don't have axle stands.
What I did is simply jacking one side and put 2 bits of wood under the wheel, then doing the same with the other rear wheel. So the rear of the car was raised by about 20 cm.
No need to remove the bumper, all you need is removing 3 bolts (between cat and rear exhaust). Depending on the age of your car, these bolts can be severely corroded. Put large amounts of WD40 on these bolts and use a proper 6-sided socket (size 15) to untighten the bolts. You maybe need a "lenghtening tube" ...
On the other side of the exhaust, there are 2 or 3 smaller bolts that are easier to remove.
Fitting the new exhaust is just the opposite. Put some copper grease on the bolts, or even better, buy a set of "cat saver" stainless bolts from Mike Satur.

If you have the proper tools from the start, the job should take about an hour.



The tip re the stainless steel nuts is well worth while...took several weeks of WD40 for me to get the rusted nuts off without breaking anything....stainles steel nuts now on (and stainles steel bolts in other places, especially inside the front bonnet area)...can't understand these are not standard for cars of this price range.

Thanks for the tips - I'll get some of Mike's nuts (sorry about the double entendre).
I could still use some visual clues though... ; )
John Philpott


I wouldn't bother fitting it yorself.

Just take it down to the local exhaust fitting place - they'll do it in 5 minutes. Give the chap a tenner for some beer and an ice cream and you'll both be happy.


John - full marks for enthusiasm, but don't do it, follow Paul's advice.

Those nuts can be a real b*gger to get off, not something to cut your teeth on.

Have a go at changing the oil or the plugs instead.

John Thomas

It depends on the age of the car. During the MG world exhaust test we had a brand new car thus the nuts came off easily and the other was Rob's which needed a gas torch to heat the nuts up to remove.
So yes the job can be simple but can also be a bl**dy nightmare.
One thing that you have to be careful about is that the studs on the CAT don't shear off when undoing the nuts.

Tom Randell

I see.
Well, I jacked it up last night and had a good look at the nuts (armed with a can of WD40).
The brace is fine - it was replaced a month ago by the dealer.
The cat nuts are another thing entirely - took me a while to find them under all the rust and other debris...
I've sprayed them with half a can of WD40 but I don't hold out a lot of hope.
Still, undeterred, I'll give em a few more treatments and then have a go at moving them.
John Philpott

As an ex-mechanic who would like a quid for every exhaust I have replaced I can only emphasise what others have said rusted on exhaust nuts can be a swine to remove and on the *F* the problem is compounded by the difficult position.

As John says try something simpler to start with - the K&N filter is a worthwhile addition and is fairly straight forward.

Ted Newman


Hmmm, not sure i can help you with the pictures you requested - you would have thought that with the amount of times i have been involved with exhaust removal/refitting i would have some images of the process by now...

From an advice point of view, if the nuts securing the exhaust to the cat are older than 6 months, take it to quick fit - you will not regret it. If you attempt to remove these nuts yourself, i predict that your enthusiasm for modifying your F will be severely dented.

Hope this is of some use

SF (about to trawl his hard drive for underbody images)
Scarlet Fever

None of the exhaust fitters I called would touch it - they say they'll only fit ones bought from them. I have found a local garage that will do the job on Saturday morning.
I'm really not happy that the factory fitted nuts are so damned bad - I should have been able to do the job easy.
What would really help me now is if anyone has any pointers I might need to pass onto the guy at the garage (just in case he hasn't touched an F exhaust before)
Thanks for looking for the pics SF - they'd still be nice to see if you find any.
John Philpott


All cars that do not use Stainless Steel nuts, and not many do, will have this problem, it is just that on the *F* they are a little more difficult to get at.

Ted Newman

Of interest the same nuts used in other Rover exhaust applications are less prone to the corrosion, almost certainly due to being less exposed to the elements. The very high temp variations that occur adds to the errosion.

I think that any garage will have a 'nut splitter' which is likely to become the only sound way of removing the rusted nuts and leaving an amount of stud thread available for re-use. Alternatively the other option is to grind or cut off the nut with the stud, drill out the remains of the stud from the car flange and replace with new nuts and bolts. This does allow freedom to easily replace in the future.

Having said all of this I do have stainless steel nuts on my car. It's also worth mentioning that these are long cap nuts so fit over ALL of the exposed stud thread and seal it from the elements.

Roger Parker

I just got my dealer to fit the Cat Saver nuts on my first service so it was easy when it came to fitting a new exhaust. An exhaust center will use a welding torch to free up the offending nuts and most should do it for you in the hope of future business from you.

Having spent a few hours in a car park, in the rain, under a Vauxhall Viva, 20 years ago fighting with rusted exhaust nuts I got the Cat Saver nuts as soon as I heard about them as an option.
Tony Smith

This thread was discussed between 18/07/2000 and 21/07/2000

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