What's this?

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My tercel:: '84 SR5

What's this?

Post by spencercat » Fri Feb 09, 2018 9:52 am

Just refilling my tranny case and noticed a bad leak from a pipe which connects to a bell-shaped thing, then goes to the exhaust(?). Can anyone tell me what THIS is, marked in photo? Also, am I right to think that the tube with the arrow pointing to it is the culprit for the leak, and that there should be a hose clamp holding that hose on over the hump on the pipe?
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Re: What's this?

Post by splatterdog » Fri Feb 09, 2018 10:32 am

Just a pumpless air injection setup, it carries no oil. It's likely wet from a leaking distributor o-ring or possibly just oil changes. Look above it. Smell test also. Gear oil is unmistakable.

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My tercel:: '84 Tercel4wd w/extensive mods
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Re: What's this?

Post by Petros » Fri Feb 09, 2018 8:38 pm

Splatt is correct.

The tank a resonator chamber, that also has a reed valve, it allows the pulses from the exhaust to draw in fresh air, that comes through the tube (with purple arrow), where the inlet is behind the alternator. the idea is that fresh air, with oxygen, is sucked into the catalytic converter and it allows complete break down of any remaining hydrocarbons. has the effect of an air injector, but it requires no pump (like the early air injector systems had) by taking advantage of the normal pulses in the exhaust stream.

in most states there is no longer an enforcement process so it can be removed and discarded. I did that with mine when my cat fell apart, so I by passed it with a straight pipe. with nowhere for the air injector to connect, I took it all out. Just as well, I always curse at it every time I have to go down in there for other reasons and it is always in the way.

I always thought it was odd they just sucked in unfiltered air, without any screen or anything over the inlet.
'87 Tercel 4wd SR5 (current engine swap project)
'84 Tercel 4wd (daily driver, with on going mods)
'92 Mazda MPV 4wd (wife's daily driver)
'85 Tercel 4wd DLX auto(daughter's daily driver)
'01 Honda Civic (other daughter's daily driver)

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My tercel:: 1984 Tercel 4WD

Re: What's this?

Post by oldfaithful » Sat Feb 10, 2018 7:40 am

It must be installed for US emissions, the Canadian models don’t have it, my mint Texas Tercel has it and I bought one from North Dakota for parts and it has it also, you guys also have a much bigger converter than ours do, which makes the intermediate exhaust pipe have to be longer because our converter is roughly 6 inches shorter.

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