Hi all,
I just purchased my first civic (a '93 hatchback) with 153K miles and a D15B8 engine. It needs a new clutch and smokes a little (white smoke). The antifreeze and oil don't appear to be mixing, so I'm assuming it's just a head gasket. While I'm tearing the engine apart to replace the head gasket, I figured it would behoove me to replace the timing belt as well. I'm also, of course, going to change the oil, spark plugs, and distributor while I'm at it, since I have no idea how recently it's been maintained.
I have a couple questions, though; all the info I've read recommends removing the transmission to replace the clutch. As long as I'm taking the intake, exhaust, and head off, would it be simpler to change the clutch from there, instead of putting it all back, then removing the transmission?
Is it recommended to replace the flywheel with the clutch? Some sources didn't mention it, while others seemed to assume that you would.
Lastly, since I'm going to have the car in so many pieces already, is there anything else I should check/replace? I want to get 100k out of this car, so I want to do whatever is needed now, rather than having to tear the engine apart again in a year.
Also, I've replaced lots of starters, alternators, water pumps, etc., but this is by far the biggest undertaking I've ever taken on. I hope I'm not getting in over my head :-)
The only other problem with the car is that it will pop out of second gear when you let off the gas; is this a problem? I assume it's just a nuisance (I've had trucks do that before with no ill-effect), but since I'm taking everything apart, is there anything I could do to fix it?
Lastly, the last owner apparently did a bit of modding to it; it has a custom header and exhaust, K&N-like intake, plug wires, and I have no idea what else. He rattled off a few things that I don't recall. I'm going to attach a picture of the engine compartment; is there anything I should be concerned about? Is there anything else custom under there that's a 'big deal'? To be honest, I'm a classic Ford truck kinda guy, and this is my first Honda (unless you count my '81 Goldwing), so I'm a little inexperienced.
Oh, and in the picture, you can see that the radiator is slightly closer to the engine than it should be, due to a slightly bent frame. This doesn't appear to be a problem; nothing mechanical was touched, but I'm going to bend it straight again.
Thanks!

 

to check for head gasket leak get the radiator completely full then start the engine cold with the cap off and rev it. Constant bubbling means there is a leak.

For that much work I'd consider removing the engine / transmission assembly and working on it outside the car. It's really not that complicated to do, and then of course you have very easy access to all parts.

Popping out of gear is often a bad motor mount letting the engine shift around and pull on the linkage.

That kinking of the top radiator hose suggests you have a D15B2 engine in there, which is almost identical to the stock D15B7 except for little details like the angle the hose comes out. Fix that somehow, you're not getting good water flow that way.