I have what seems to be a very noisy air pump....the belt driven attachment on the passenger side of the engine. Any opinion on whether i can remove the drive belt so that i can continue to use the car while a new part is ordered? Is the air pump strictly a smog related item or does it have some other important function which would not be good to disable. My mechanic is 30 miles away and i'd rather drive then than flat bed the car.

87 eurospec auto\
silver/black

 

No problem to remove/cut* the belt. NOx emissions will go up, but it will not damage the converter.

The pump has no other function than to supply the oxidizer (rear) section of the cat with oxygen.

*Side note: I found that if you don't have the A/C pump, and you cut the air pump belt, the alt and PS pump belts will lose significant tension.

 

Cut the belt and if you feel adventures remove the pump, hoses valves, etc. My car runs better without............YMMV.

Check out previous threads!

 

Flyin....looked for previous threads under 'air pump' but nothring really came up....think i'll cut the belt and then keep an eye on the tension for the two remaining belts, having already removed the AC pump belt.

87 eurospec
silver/black

 

search for "smog pump" rather then "air pump"

You will find TONS of info!

If the pump is getting noisy - it is most likely that the pump's bearings are going. If it does sieze, it will likely QUICKLY break the belt - which could easily get entangled in your other belts - causing THEM to break! I would get it disconnected ASAP!

Also - the added drag of the bad pump is probably robbing you of a couple HP!

 

Not sure about your year, but on my 84' the belt that drives the air pump also drives the mechanical fan for the radiator.

 

His sig show it as an 87...so no belt-driven fan. He should have no problems just cutting the belt.

 

Hi All,

Just looked at what i assume is my air pump filter (Percolator Filter around 2 inches in diameter and around 4 inches deep) that needs changing ,its in a small metal drum with a wing nut on top near my nearside front corner on a RHD english 86 928 S2.
After reading about air pumps on search ....I have a quick question...as my car has NO cats,,,,what does the air pump system do ??? and do i need it for anything ?
All the best Brett
928 S2 1986 AUTO

 

It does NOTHING but suck a few HP. You do NOT need it!

 

Brett,

I think the S2's inject air into the head, which ejects after the exhaust valves to help burn any remaining gasoline. They also have steel inserts in the head at the exhaust manifold connection because of the additional heat?

 

Thanks for replies.....interesting....so if i remove the air pump system will it affect my MOT emissions readings ? Is there a possibility they will fail as the readings will be too high after removal ?Any UK owners removed the system ?
Brett
928 S2 1986 AUTO

 

Brett..........your car has no cats so removal of the air pump will not make your emmisions reading worsen. Does your air pump have its own drive belt? If so, cut the belt and when you have the time remove the pump and its associated hoses and valves.

If you have the drive belt that does all the accesories than you remove the air pump and use a shorter belt..........again a good search will find the correct 'new' belt length.

 

In Finland 928 owners are constantly having trouble in yearly inspection as there is too much oxygen on exhaust because air pump is pumping it there. Depending on what is measured and what are allowed limits on MOT it's possible that functioning air pump will cause trouble unless it's disconnected or air line to heads is blocked during measurement.

 

Well.....i cut the air pump belt off today and started the car and i've still got the noise which i talked about on a previous post.....1500 kms after TB/WP....all of a sudden there's a loud knocking noise which i thought was coming from the air pump. Guess its back onto the flat deck and back to the mechanic. On a positive note i just finished installing the Jager GTRSS shift kit, leather/ aluminum shift ****, leather boot and brushed alum console plate. What an awesome upgrade, looks wise, from the old T handle shifter. Hopefully i don't have serious engine problems so i'll be able to enjoy it before my insurnace runs out at the end of Sept.

87 eurospec
silver/black

 

I cut my air pump belt over 6 months ago and just recently passed California smog without it. 89 car, 200,000 miles.