How To: Fit a Stainless Steel Flexipipe

[zipimini]

OK, First you have to purchase the new Flexipipe. I bought the stainless steel one from Autobits with the 'Fitting Kit' to save me any hassle with missing bits. Total cost was around £65.00 delivered. The exhaust looked good and there were plenty of bits in the fitting kit..........BUT.........the nuts and bolts in the kit were the WRONG size!.....not good! So, luckily, I had a selection of nuts that fitted so I used them.
Here's a list of things I needed:
Exhaust
Exhaust Kit
7 new nuts (not in kit)
15mm Socket
17mm socket (new nuts)
8 inch extension bar
Pry bar
Hammer
15mm combination spanner
17mm combination spanner
Lead light.


1: Jack up the car chock the front wheels and put axles stands under the subframe. Try and get the car as high as possible to give you enough room to work. Basically there are 7 nuts to undo on the F (9 on the TF I think) and one rubber exhaust bush. The first picture is undoing the exhaust to catalyst nuts (3). These can be tough so a good soaking with Duck Oil or WD40 will help.

exhaust3.jpg

2: Next is to undo the 4 nuts on the exhaust to manifold section, Now this is not easy! The two lower nuts will come off using a socket but the two upper ones are real Bas***ds and I ending up using a ring spanner and turning one flat at a time because there is no room for a socket.

exhaust5.jpg

exhaust6.jpg

3: Once these 4 bolts are undone the exhaust will be supported by the exhaust rubber. slide this off (with force). Then at the catalyst end you may have to undo the nut for the 'strappy thingy' then wiggle the exhaust back box away from the catalyst. The flexi-section should then wiggle out, make sure you remove the old gaskets as well.

exhaust14.jpg

4: Compare the old and new.

exhaust8.jpg

5: Now to fit the new exhaust. First throw away the bloody useless nuts they give you in the kit because THEY DONT FIT! Position the exhaust loosely in place. The exhaust is a really, really, tight fit.I put the manifold section in place first and bolted it in place. DONT FORGET YOUR GASKET!. The catalyst section was about 1/2 inch out on the catalyst holes and I needed the pry bay to get the holes to line up.

exhaust10.jpg

exhaust13.jpg

6: Eventually I managed to get all the holes to line up. I undid the 'strappy thingy' so I could get the bracket to go on and DONT FORGET YOUR GASKET! I did all the bolts up and then attempted to put the exhaust rubber back on.

exhaust12.jpg

7: Another problem. The position of the hanger bracket was about 1/2 inch or so out from the original. This made putting the rubber back on almost impossible, so I had to 'adjust' the subframe hanger bracket with a pry bar to get it to fit well.

exhaust12.jpg

8: I also had a lot of problem with the 'strappy thingy' going back on but after much struggling and hammering I got it to fit.

exhaust14.jpg

9: The fitted exhaust

exhaust15.jpg


10: Started the car and tested all OK. I would say your looking at about 2-3 hours if you have a few problems, less if all goes easy (so budget on 2-3 hours!!)

My overall impression of the new flexipipe was it's good quality, crap fitting kit (but still worth it for the gaskets) and its a very tight fit but it did go together and the exhaust note is good.

[MG_CHIC]

Excellent how to guide mate! Well done!

Incidently you have exactly the same downpipe as mine which I fitted only yesterday - spooky eh? *cue x-files theme tune*

Took about an hour with Technozen's help (cat had been off only a couple of weeks ago so no rusted bolts!).

My only additional tip (and this is more for the ladies) is for the love of God cover your mouth & eyes! The amount of rusty crap that flaked of the bottom of the car & landed in my mouth & eyes was unbelievable! I think I must have swallowed half my engine!

[Sparty83]

I fittied the same downpipe today along with a new cat (supersport should be here tomorrow :P). I found the downpipe to fit very well and good quality. The only problem I had was 2 of the bolts to the manifold, ended up un screwing the studs with nuts still attached on two.

The fitting kit as described, wrong nut size but I used the cat nuts as I had a fitting kit for the cat too. Found the hanger bracker a bit short but no problems there.

So new downpipe and cat on, backbox to go and it should be very easy since I have all new bolts on the cat

[zipimini]

Originally Posted by MG_CHIC

Excellent how to guide mate! Well done!

Incidently you have exactly the same downpipe as mine which I fitted only yesterday - spooky eh? *cue x-files theme tune*

Took about an hour with Technozen's help (cat had been off only a couple of weeks ago so no rusted bolts!).

My only additional tip (and this is more for the ladies) is for the love of God cover your mouth & eyes! The amount of rusty crap that flaked of the bottom of the car & landed in my mouth & eyes was unbelievable! I think I must have swallowed half my engine!

Looks like Slave really has had a major makeover Kara!!........next on my list is .............cupholders!!!

[zipimini]

Originally Posted by Sparty83

I fittied the same downpipe today along with a new cat (supersport should be here tomorrow :P). I found the downpipe to fit very well and good quality. The only problem I had was 2 of the bolts to the manifold, ended up un screwing the studs with nuts still attached on two.

The fitting kit as described, wrong nut size but I used the cat nuts as I had a fitting kit for the cat too. Found the hanger bracker a bit short but no problems there.

So new downpipe and cat on, backbox to go and it should be very easy since I have all new bolts on the cat

I was impressed with the fit and having been quoted £145.00!!! for a genuine Rover unit, I think it is a great piece of kit. I was disappointed with the fitting kit though, but at £3.00 odd I wouldn't have got the gaskets for that anyway.

[Villager]

Great guide - I'll be replacing mine this week.

What size nuts and bolts did you use?

[technozen]

Don't forget to use a copper based anti-sieze grease on the various nuts and bolts... it will make disassembly easier if any exhaust work needs to be done at a later stage.

By the way Kara, this was the source of the smoke when you took the car for a test drive!

Originally Posted by zipimini

So, luckily, I had a selection of 'Nyloc' nuts that fitted so i used them.

Nyloc nuts are probably not the best choice for this application, the plastic insert in the nut will melt!

The manifold-to-downpipe nuts are M10 as are the rest of the flange-to-flange nuts and bolts on the exhaust system.

[MG_CHIC]

Originally Posted by technozen

Don't forget to use a copper based anti-sieze grease on the various nuts and bolts... it will make disassembly easier if any exhaust work needs to be done at a later stage.

By the way Kara, this was the source of the smoke when you took the car for a test drive!

Oh I see! Well that's a relief! Thanks mate! Oh btw guess what... you know my steering wheel? It now leans to the right instead!

[zipimini]

Originally Posted by technozen

Nyloc nuts are probably not the best choice for this application, the plastic insert in the nut will melt!

The manifold-to-downpipe nuts are M10 as are the rest of the flange-to-flange nuts and bolts on the exhaust system.

I've been using Nylocs on various exhausts and the inserts do harden but they still lock on very well. I've not had one round itself coming off either, unlike the flanged OEM nuts.

[Villager]

Finally going out to fit this today (and investigate the vibrations since fitting the TT) so fingers crossed.

[CJJ]

Originally Posted by technozen

Don't forget to use a copper based anti-sieze grease on the various nuts and bolts... it will make disassembly easier if any exhaust work needs to be done at a later stage.

By the way Kara, this was the source of the smoke when you took the car for a test drive!



Nyloc nuts are probably not the best choice for this application, the plastic insert in the nut will melt!

The manifold-to-downpipe nuts are M10 as are the rest of the flange-to-flange nuts and bolts on the exhaust system.

Originally Posted by zipimini

I've been using Nylocs on various exhausts and the inserts do harden but they still lock on very well. I've not had one round itself coming off either, unlike the flanged OEM nuts.

I noticed the nylocs too



I personally wouldn't use nylocs on high temperature applications, such as exhausts etc, as the plastic is not rated for this and could easily melt and allow the joint to come loose.

I would use Aeronuts (Aerotight) or normal nuts with high temp threadlock or spring washers.

An example of an Aerotight nut

[Neil Surrey Lab]

Nyloc nuts no good mate, they'll probably fall off! the nylon bit will melt in them

you need to get some flange nuts for that

[Villager]

All done! Took about two hours all in. The trickiest parts were getting the nuts off the manifold (a selection of bendy socket adaptors is most useful), and fitting the new pipe to the rubber hanger, which really has to be done first.

Old and new:



The old pipe doesn't seem to be in bad condition, but the blowing/whining/rasping sound has disappeared, so it was clearly at fault.

As often happens with the MG, whilst fixing this problem, I found two others. The first is that my coolant pipes are pretty rotten, and will duly be replaced. The second is a slow oil leak dripping from the gearbox. Wish I hadn't looked! What is the likely culprit?

[jonathanharding]

Hi
Will be getting one of these and their cat when I replace my exhaust.
Cheers for the write up.

[CJJ]

Originally Posted by Villager

The second is a slow oil leak dripping from the gearbox. Wish I hadn't looked! What is the likely culprit?

I had a slight weep from the selector rod. The one that the cables attach too. I assume the seal on the rod was letting a small amount of oil past.

Unfortunately, if it is this, it is a gearbox stripdown, as the seal is fitted from the inside of the gearbox. I managed to get a new box for around £110, but otherwise would have just lived with it as it was such a small leak.

[X84REO]

i just had a look on autobits. is the downpipe stainless steel as it didnt say.

[technozen]

Having fitted one of these to Kara's F they are definitely stainless, I would expect that they use 409 grade based on the retail price.

[X84REO]

does anyone know if the cats on autobits are stainless steel

[bgunn]

Originally Posted by CJJ

I had a slight weep from the selector rod. The one that the cables attach too. I assume the seal on the rod was letting a small amount of oil past.

Unfortunately, if it is this, it is a gearbox stripdown, as the seal is fitted from the inside of the gearbox. I managed to get a new box for around £110, but otherwise would have just lived with it as it was such a small leak.

No it isn't! It has a lip around the outside that you can use to pick it out, then carefully tap the new one in with a drift..

Brian.

[CJJ]

Hmmm. Seems your right, I should actually look at the book sometime. I was advised differently when I asked about the leak and didn't have the book to refer to. Never really revisited it as I new I was going to strip the box at sometime anyway.

http://forums.mg-rover.org/showthrea...arbox+oil+leak