curt_928

Hi everyone. Just read one of the threads and mentioned that deleted the air pump for PCV.. I live in a non-emissions paranoid state and don't have to worry about catalytics etc. Can we just remove the air pump belt and voila! ? Do we have to worry about backfiring, blowing gaskets etc. once removed?

Would be nice to eliminate that parastitic engine component...

Many thanks,

Curt

AO

Usually, you want to remove the air pump when you remove the cats. Not sure if cutting the air pump belt would help/hurt while leaving the cats in.

123quattro

You can take the pump off while the cats are still there. You will need to put a cap on the air feed line that runs to them. Otherwise, you will have a weird sounding exhaust leak.

Mike Frye

Hey Curt,

What model year is it? I think the S4s (87up) have an electric fan, but before that the air pump belt is also the fan belt, so you would have to either get a shorter belt (and have no way to tighten it), remove the pump and replace it with a pulley, or also add an electric fan as part of the switch.

I think you should replace the cats with some that weren't designed to have air infusion, like the high flow ones you can get as part of a crossover pipe upgrade. This way you still could pass inspection if you wanted to, and you know they're working the way they were designed. Not sure what effect a non-working air pump would have on the stock cats.

curt_928

Hi Guys,

Thanks for the replies! The car is a 79' that I installed a cat bypass on 1 1/2 years ago. Right now the air pump just feeds into the crankcase I believe... The pulley idea isn't a bad one. I'll have to check on that tonight.. maybe even a shorter belt.. hmmm...

Thanks for the help!

Curt

123quattro

When I removed my air pump, I spaced the cooling fan out about 3/4" and put it on the power steering circuit with a longer belt.

j.kenzie@sbcglobal.net

That's ingenious. I used a 21" v-belt from crank to fan directly, maybe a 4L2100 fractional horsepower type ( a lawn mower belt). There is not much stress on it so I think it will drive my fan OK.

PorKen

CIS engines have air injection into the heads, which exits at each exhaust port, to further burn any leftover HC.

KY928

This is what I ended up doing. Bought a 1/2"x21" belt at Tractor Supply. I had the fan off, so I bolted it on with the belt. Tight fit, works great. It's a Kevlar belt, so very strong.