Remove Smog Pump? (Corolla Alert!)

[mikey]

Once again, I count on the old Tercel Board to help with a (hopefully) similar design. I'm thinking of completely removing the air conditioning system. It's drained, and the belt has been off for years. There's less room under the Corolla hood than the Tercel one, and I'd love the extra work room. I suspect that the starter is under there somewhere, for instance, but I can't see a thing.

Above the AC compressor is a belt driven air pump, I guess it's what they call a "smog pump." The belt is off of this unit too, and I'm not sure that it could be put back without the AC pulley being there too. The exact routing of the belts is a mystery to me. This air pump system, another mystery to me, draws air from above the carb and I'm assuming shoves it to the exhaust manifold. Questions: Can I completely remove this unit? Does running the car with the belt off (as it's been for years, possibly) damage anything, or affect miles/gallon?

[dlb]

not sure, can you post some pics so we can see how the belts and pulleys work with each other?

[marlinh]

I believe those air pumps were for cleaning up emissions. I've seen many vehicles with those pumps disabled. Not sure what it would do for gas mileage except that the engine has one less thing to drive, like the ac compressor. It wouldn't make that much of a difference for mileage. If you remove the pump, somewhere downstream you will have to block off a pipe that goes to the exhaust, usually it comes in in front of the catalytic converter. That's what I seem to remember...

[Petros]

remove it all, plug up any holes the plumbing leaves behind. You will be fine.

These pumps were an early attempt to get some O2 into the exhaust up stream of the cat to assist in downstream emissions clean up. Now they use reed valves to take advantage of the natural pulsing of the exhaust. the car will run fine without it, if it sits that long it gets internal corrosion from exhaust gases bleeding back though the system. It is junk now anyway, and it will not harm a thing to remove it. "Back in the day" (I can not believe I am saying that), I have removed more than my share of smog pumps. I think their utility was marginal anyway and they reduced economy and efficient too. No one liked them much.

[mikey]

Whoo Hoo.....

Thanks, Petros, that's what I wanted to hear. I never really wanted to even think about the belts, etc.; I just needed a go-ahead to pull the whole thing out, AC, smog pump, whatever is loose.You know, if it was hooked into any of those vacuum lines, etc. around the carb, I'd be more cautious, but there's just a two inch or so hose which disappears somewhere toward the exhaust pipes.

Once again, I thank the powers that be that I live in an area with no emission testing, and drive a relatively simple machine.

P.S. "Back in the day" I drove a Beetle. Simpler times!

[Petros]

Usually there are threaded flare hose nuts for the hard tubes, find the correct size metric plugs to put in the holes in the ex manifold (there used to be one for each exhaust port, so you should need 4). The later ones there was just one large inlet to the manifold. Either way, get the correct plugs for all the holes, cap off the vac ports, or remove the fitting and install a plug. After these plugs have been in for a while almost no inspection will even notice that these plugs are ot "original equipment". Most states do not require inspection emissions inspection after it is 25 years old, (california is one exception), so even if you eventually sell it in a area that does require inspection, not likely it will be an issue.

Strange thing is there are federal regs that require this equipment to be operational in all cars, the practical matter is the depend on the states to enforce it (there are no federal emissions inspections). And if a car older than 25 years is exempt, than there is no practical means of enforcement. Presumably, when a car gets older getting the parts to maintain the emissions systems becomes impossible since this is longer than the federal government requires the dealer keep parts available for the older existing cars, so I suspect this is a recognition that there are not many cars older than 25 years old on the road, and it allows you to keep driving it and owning it even if you can not buy replacement emissions components. So I do not know what the legal status is when you "tamper" with a system like this, but it seems to me making the car more efficient by removing that stuff means you will burn less fuel per mile, and that has got to be better for the environment. The states allow you to register and drive it without passing an emissions test, so they are giving you permission to drive it.