Car Repair - what fun!

Another marvellous feature of retirement is that you have the opportunity to mend your own car.  I understand that you, dear reader, being generally of sound mind, are only too happy to pay someone else to get their fingernails filthy grubbing about underneath your expensive status symbol, but I am made of sillier stuff.  Particularly silly when it's a cold, wet February, the fault is an exhaust system leak, and I don't have either a usable garage or a flat drive.

What I do have is a pair of 10ft long car ramps made of Dexion. 

Dexion car ramp - slightly bent

I originally made them to transform our sloping drive into something horizontal, so that I could at least change the oil in a Toyota MR2 Mk1 which I owned a long time ago.  Since then they have held up all sorts of vehicles, including various camper vans, some of them even with sleeping guests aboard.  This last use case is definitely beyond the safety limits of the design, so I now prop them up with axle stands and bits of wood for camper vans, but they are still good for cars if used carefully.  They are about a foot high at the garage end, so you can get quite a long way under with gradually diminishing headroom.  I roll carpet out underneath, which makes it quite cosy under there, as long as it doesn't rain too much.

At the moment, of course, the drive is somewhat obstructed by bits of garage roof, still waiting for their moment of glory.  But blown exhausts wait for no man, so I had to just go for it.

The first issue is that the broken flexible part of the BMW 118d's exhaust is not a part which anyone lists.  It turns out that BMW think it's part of the catalytic convertor box, since it's welded on.  So you need a special aftermarket part, which is a bit more difficult to locate.  Only a bit, of course.  We have the internet, and the internet has the delightfully named Every Exhaust Part Ltd., who do the business with their special repair kit.

So far so good.  The exhaust system is stainless throughout, so it's fairly easy to dismantle, except for the nuts and bolts, some of which are still made of the traditional rust.  The "access only one end at a time" feature of the ramps results in a lot of farting about to get everything undone, but hey.  The new bits arrive (clamp included!), the catalyst box comes off under the car with only one slight mistake - there is a bracket which you get at from underneath, which has studs welded onto it so that you can just undo the nuts - lovely.  Then there's a bracket where you can see the nut from the top (with a big long extension on your socket) so I expected the same genteel, mechanic-friendly design.  Only it was a bit stiff, so I put my big breaker bar onto it... still very stiff... actually VERY stiff... BANG!  Turns out that this time, the nut was welded on, and you're suppose to remove the bolt from underneath.  Oh well, it got the bits on the bench.  This is what they looked like, with the old flexi now missing its pretty woven skirt.  I'd already started in with the angle grinder by this point.

Here's a more detailed view, for annotation nerds:

1.  This weld holds the cat. exit pipe onto the catalyst box - needs to stay and be gas-tight!
2.  This weld holds the old flexi on to the cat. exit pipe - this must go (all of it) to expose the pipe underneath (5)
3.  This weld holds the heat shield / cover onto the catalyst box.  Ignore.
4.  This is what happens when you remove a bit of (2) with an angle grinder, exposing the sleeve of the flexi underneath
5.  This is the exit pipe we have to keep
6.  This is a bit of weld metal peeled back

It's marvellous what you can do with an angle grinder!  I removed all the old flexi and its associated weld to leave a nice shiny exit pipe in what we non-time-constrained people call "no time at all".

All looking good, offer up the new part - aaargh!  It's super floppy!  Have I ground off too much?  I instantly consider making a sleeve from the middle section of the old flexi, but really, this can't be right, can it?  After a cup of tea, I measured it up. The pipe is 60mm OD, the new sleeve is 65mm ID.  Hmmmm.

It seems Every Exhaust Part Ltd. stock slightly too many exhaust parts to keep track of, and there's an almost exactly similar part with a bigger inlet pipe, which they have sent by mistake.  They were very nice about it and rushed me out a new one.  Meanwhile, I don't care about he delay, because we still have plenty of functioning vehicles.

Almost exactly similar

Actually the parts are more nearly identical than this photo suggests. It all went back together fine, except that one of the rear hangers turned out to be broken.  The rubber mount holds a bent rod which is welded onto the side of the pipe, but the rod had broken part-way through at the end of the weld.  I have a MIG welder, but no stainless MIG wire, and I couldn't face the idea of farting about with the one-end-at-a-time ramps yet again to take it all off and put it back again; so I made a custom clamp by drilling/filing a slot in a U-bolt style exhaust clamp (from stock, natch) so that it clamps the rod against the pipe in a nice controlled way. 

Custom lamp in lieu of (broken) weld

Seems to work.  Not stainless, mind. Oh well.

Meanwhile, I notice that if you had a nice big garage with a 6" thick concrete floor, you could buy a lovely two-post lift just like the one your local repair garage uses for as little as £1200!  Ah.  Such is the stuff that dreams are made of.  Silly, eh?