Saturday, April 18, 2009

An Exhausting Day

Today was set to be a busy one ... but mostly not because of the car. I started out at 5:20am, getting up and packing the car with soccer equipment to drop off for the first day of the season - I'm the coordinator for the youngest age groups at our local youth club Chantilly Youth Association - about 700 of the c. 2300 players in the soccer program. Then back home and out again at 7:15am to take my oldest daughter to the "Solo & Ensemble Festival" for her flute recital. Next back home to pick up the youngest and take her to breakfast at IHOP for her birthday (she's 11 today) and from there to her volleyball game (also part of Chantilly Youth Association) - her team won their match 3 games to 0 :). That done, back home to cut the grass and kill a few weeds ... whew ... finally time to get something done on the car.

The last remnants of 'gasness' remaining are the exhaust system and the fuel system. The catalytic convertor, exhaust pipe and muffler are hung from brackets using rubber hangers that are easily pried off with a screwdriver (or if you're not going to be reusing them like me, cut with a utility knife). That leaves the cat lying on the ground.

But the muffler and exhaust pipe are hung up on a brace that connects the 2 sides of the rear subframe. I guess if I disconnected the cat from the exhaust it would be possible to pull the pipe out over that bar, but no way is that happening with the cat still attached (and you'll remember how impossible getting the bolts off the cat was when I was trying to disconnect the down pipe when taking the motor out).

So that bar is coming out ... note to self ... just because something looks like a nut doesn't mean it turns like nut. If you look at the connection you'll see a bolt that goes from the underside through the bar and is capped by a nut on top. I spent about 20 minutes trying to loosen that nut before I looked closely and found it was welded to the subframe! Loosening the bolt was a lot easier! With that done, the exhaust system was out (note that was after I had completed the tasks below - I had to 'think' a bit about why that nut was not moving).

So now on to the fuel system. The fuel tank in the Miata sits in a cavity between the trunk and the passenger compartment. Very safe I'm sure, but not very convenient to remove. The only way to do it is to drop the entire rear subframe to make room for the tank to drop down and be removed. I've seen a couple of Miata conversions that decided the effort was not worth it and simply drained the tank, capped the lines and left it there. However I want that space for batteries so it's coming out. Luckily I found a good article at that gives a great procedure for removing the tank.

Unlike the factory procedure, this one leaves the torque arm attached to the differential. This means that the wiring conduit clipped along it's length needs to be disconnected - squeezing the plastic clips on the drivers' side with some needle-nose pliers and pushing them through does the trick.

Next the ground wire connected to the torque arm at the rear gets disconnected.

Now the rear brake lines need to be disconnected. There is a single line going into a block on the passenger side just in front of the subframe assembly.

Here's another view from in front of the rear tire - the flare nut looks a lot easier to get to from here.

So off comes the splash guard to give me some room.

Then the brake lines comes off and the brake fluid starts dripping. And dripping and dripping ... essentially you're draining your brake fluid reservoir so it takes a while. So while I was waiting, back to the front of the car to see what I can work on there. Ah, ha, the charcoal canister and electrical connections for the emissions control system are still there.

So off they come.

Back under the car waiting for the incessant dripping to stop, I noticed that there were a couple of heat shields - one between the muffler and the trunk.

And one between the cat and the underside of the driver's seat (what ... no seat warmers!).

So they both come off.

That's it for today - time for a trip to the dog park with the pup, then birthday cake and finally Spike TV is showing the first Star Wars trilogy - so I'm off to watch that (yes, I'm a geek :) )


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