Replacing the Catalytic Convertor

[SamHill]

If you look at what some people have done with their exhaust.... heat shields?! heat shields?! WE DON'T NEED NO STINKUN HEAT SHIELDS!

[TTait]

Getting to at least one of the bolts holding the cat to the crossover pipe can be really tough, especially in cramped quarters under the car. A combination of socket extensions and wobbly joints helps.

You should also consider why the old one failed. These are not a wear item. Either it shook itself to pieces or it melted internally because of fuel in the exhaust. You mentioned a gas smell - make sure you are not running too rich, or not getting good combustion, or you will melt down the brand new one too.

T

[mluder]

Thanks, Chris. I appreciate the offer and may take you up on it.

Honestly I should have all the tools here to do the job I'm just nervous about crawling under the car while lefted for the first time.

I bought the wheel cribs thinking it would be more stable than stands but you're right... I have to lift it pretty high to get them under. I started to try but then chickened out when I realized how high it was. I'm either going to try again or buy some jack stands.

I'm just concerned that jack stands could tip over. I know caution is always best but I'm probably worrying too much. Lots of people use them everyday and though there are incidents of falling cars they are not that common.

I just need to do it the first time and I think I'll be fine. The good thing is, once I get it on stands, I can geta bunch of necessary work done - Oil change, Heat shield, and the cat conv.

My next house will have a sho with a lift...

Just jacking up the rear should be fine. I assume your jack goes high enough to get those cribs under the wheels? You might want to get some jack stands for later so you can remove the wheels. They aren't that expensive.

If you like, you are welcome to come to my place where I have all the tools to do this. Only drawback is I'm leaving town for a week this coming weekend. So it will be two weeks before you can stop by (unless you come over on a weekday evening).

Chris

[mluder]

That's definately a concern... I failed an emissions test on high hydrocarbons so I used a dwell meter to get the mixture dialed in. MOst of the time it sits right in spec and every so often I get these severe swings high and low. After I adjusted things, I failed a second emissions test but the hydrocarbon count was better.

I pulled 4 of the 6 spark plugs and they seem fine.
I have not checked injector spray pattern.
I think I have a vacuum leak somewhere but haven't tried a smoke test to pin it down.

When I bought the car it had sat for ten years. The PO had Toby rehap it to get the fuel system, cooling, and breaks working. While most of the fuel system is new (pumps, wires and plugs, etc) they stopped short of replacing the injectors. On Toby's advice I ran Seafoam injector cleaner through over the course of about 6-8 tanks of gas and did some "spirited" driving. Not shure if it helped or hurt.

Needless to say, I have some proceedures I probably need to go through to really address the situation.

BTW, the old one is in really rough shape - the outside is really rusted over and caked with red dust. The car had been in Hawaii for it's entire life and I am finding this red volcanic rock dust everywhere.
I would bet the insides are shot too.

Getting to at least one of the bolts holding the cat to the crossover pipe can be really tough, especially in cramped quarters under the car. A combination of socket extensions and wobbly joints helps.

You should also consider why the old one failed. These are not a wear item. Either it shook itself to pieces or it melted internally because of fuel in the exhaust. You mentioned a gas smell - make sure you are not running too rich, or not getting good combustion, or you will melt down the brand new one too.

T

[Chris4099]

I'm just concerned that jack stands could tip over. I know caution is always best but I'm probably worrying too much. Lots of people use them everyday and though there are incidents of falling cars they are not that common.

....

My next house will have a sho with a lift...

If they are properly placed and the ground is stable, you've got nothing to worry about. The weight of the car does a good job keeping them in place!

I just moved to a house with a 3 car garage. So I'm looking into getting a lift myself. Just need to verify the floor is thick enough to support it.

[TTait]

I just moved to a house with a 3 car garage. So I'm looking into getting a lift myself. Just need to verify the floor is thick enough to support it.

You may be able to add steel plates under the lift to spread the load, ask the manufacturer. The other concern is whether your garage has a post tension slab with cables running through it. If you hit a cable, or even nick it while bolting it down you will have a problem.

[Ron]

If you look at what some people have done with their exhaust.... heat shields?! heat shields?! WE DON'T NEED NO STINKUN HEAT SHIELDS!

When does it end?Bill.jpg

[nofear365]

How much different is the exhaust note without the cat installed? I'm really interested in this modification.

[pezzonovante88]

How much different is the exhaust note without the cat installed? I'm really interested in this modification.

+1

[Ozzie]

How much different is the exhaust note without the cat installed? I'm really interested in this modification.

I don't know the answer to that but I will add this:

I have been running the (stainless) DMC Stage 1 system for a while now, and it has dual cats. One of the most enjoyable parts to me of the Stage 1 system upgrade (and I expect other similar ones), is the burblling sounds between a high rev 1st to 2nd shift, that come from the unburnt gas mixture going off in the cats.

I would miss that sound very much, if I took that cats off.