1979/80 oz market kombi - EGR/pollution gear system?

Discussion in 'Engine & Transmission' started by Volksy85, Jul 16, 2018.

  1. Volksy85

    Volksy85 Member

    Messages:
    403
    Location:
    Melbourne
    Hi guys
    Looking at a 1979 bus (2.0 twin carb) that has a belt-driven Nippondenso/Bosch pump unit sitting in front of the air intake, facing outwards. It’s currently disconnected, and I can’t see how it would operate – unless the required ‘extra pulley’ has been removed from the engine.

    I assume this is EGR/pollution related. Does anyone have pics of a complete system in place, or info on how it all works?

    Here's a pic via google:

    [​IMG]
    Cheers
     
  2. rstucke

    rstucke Well-Known Member

    Messages:
    557
    Location:
    Wamberal NSW AUS
    I think it was an add on to meet Californian emissions. It blew air into the exhaust as an afterburner
    It was driven from a little add on shaft connected to the end of the fan with an extra bearing on the end on the tin ware.
    It isn't necessary in OZ and if it was me, I'd loose it. You will have to block the holes in your heads.
    Mine is the last of the bay windows with carbs and it never had this setup and past through registration (NSW)
     
    Poptop likes this.
  3. Barry

    Barry Well-Known Member

    Messages:
    2,429
    Location:
    Abbotsford NSW
    well...............NEVER seen that one before
     
  4. rstucke

    rstucke Well-Known Member

    Messages:
    557
    Location:
    Wamberal NSW AUS
    t201800.gif

    you need to block the holes in the head (number 10) both sides
    There's an EGR you can ditch as well
     
    Last edited: Jul 16, 2018
    David H likes this.
  5. Mordred

    Mordred Super Moderator Staff Member

    Messages:
    2,645
    Location:
    Penna, Hobart
    I would have though it would have been fuel injected by that year originally, not carbs. Anyone confirm? I reckon it might have been changed over and that is where the pump etc came from.

    Adrian
     
  6. wirrah

    wirrah Well-Known Member

    Messages:
    1,726
    Location:
    Lower Hunter, NSW
    My '78 Sopru had this system. Microbuses were fuel injected but kombies not so much. Also the level of compliance was still a state thing. I remember reading the handbook and it had seperate entries for Victoria.
     
  7. rstucke

    rstucke Well-Known Member

    Messages:
    557
    Location:
    Wamberal NSW AUS
    I think you could get both from about 76
    David h is injected and OZ model built here (I think), mines carbied but a latter OZ model (imported) with square exhaust ports.
    I think the air injection was only for the yanks.
    Mine also had an egr take off but was blanked off from factory.
    Very confusing.
     
  8. Wayne murray

    Wayne murray Well-Known Member

    Messages:
    1,670
    Location:
    Seven hills
    Your right rstucke. You could get both in 76 ish period then they went back to carbies
     
  9. David H

    David H Well-Known Member

    Messages:
    2,963
    Location:
    newcastle
    Ok. Mines injected & Aust build from CKD kit & has about half of what is shown above. Never had the air pump on mine. Yeah I understand it's a USA California thing & as Rick says was designed to blow air into the exhaust (not really an afterburner, more a 'put more air in to reduce the amount of pollutants as a parts per million'. (Not the first time VW cheated emissions & definitely not the last:eek::eek::oops:.)
    I blanked off most of the Aust ADR pollution stuff back in 87 (mainly EGR canister I believe). Mines original equipment so if you want photos just let me know.
    Until last Bugs & Buses recently my understanding F/I was July 76 (due to ADR 27A at the start of that month) to end of that year (also CKD kits) & then went to fully imported & back to carbs (again getting around ADR pollution laws somehow:eek:) from start 77 but saw 2 at B & B that were 11th month 76 & both carbs. One had so much rust work done it either lived next to the sea or was an import & the other was a 1600 with a transplant 2litre so I can understand why no F/I & it's body was similar to my old orange one...a 6/76 model rust wise (all the usual places;)).
    Some more interesting stuff here from Andrew.
    http://forums.kombiclub.com/threads/freshly-rebuilt-engine-oil-light-on.54367/page-3
    Cheers
     
    Last edited: Aug 13, 2018 at 2:26 PM
  10. paul77

    paul77 Well-Known Member

    Messages:
    919
    Location:
    Brisbane
    Pretty sure this is referred to as a smog pump. I have remnants of this system on my imported 77 bus. It reduced the pollution PPM reading at the exhaust by introducing more air, as David H stated. VW tried everything to retain aircooled engines it seems but emissions legislation was hard to meet.
     
  11. Mordred

    Mordred Super Moderator Staff Member

    Messages:
    2,645
    Location:
    Penna, Hobart
    Thanks for clearing that up. I knew there was a period where the upmarket models would have injection like when you had a choice of Type 1 and Type IV engines in the mid 70’s.

    Adrian
     
  12. rstucke

    rstucke Well-Known Member

    Messages:
    557
    Location:
    Wamberal NSW AUS
    ADR 27A which started in July 1976 governed the maximum grams per kilometer a new unsold vehicle could emit. Back then, once sold and registered it no longer applied (in the sense that the DMT didn't have the authority to test once bought and registeredo_O) the only enforceable law back then was that emission equipment could not be removed. The test lab in NSW was on Rookwood road between Bankstown and Lidcombe in a building within the old hospital grounds. This is where they tested new vehicles according to the California Cycle. This was achieved on a Road Load Dyno (very different to a maximum torque dyno). Officers would intercept vehicles destined for dealerships either from the manufacturers in OZ or in the holding yards at Botany (NSW) for imported vehicles. The cycle consisted of driving at different speeds and gears on the dyno. The driver (me in some cases) would follow information on a scrolling paper roller that was placed on the bonnet. It dictated when to accelerate, decelerate, change into a particular gear (for manuals) and when to idle. All of the exhaust went into a centrifuge and measuring devices. There was also a shed test whereby the vehicle was placed in a chamber (mimicked a large single garage) directly after the dyno test and left for 24hrs. There were sensors in each corner of the chamber which detected hydrocarbons emitted from the tank, carbies, engine and plastic trim of all things (the shed test was the reason for charcoal canisters). If the vehicle failed the vehicle makers head office was notified and invited to rectify the problem. If the vehicle failed on the second attempt that model could not be sold in NSW until it past the test. Usually the vehicle maker sent a technician to tune and observe the test (you can imagine the shit fight)
    The EPA absorbed all this when it started 1991

    Anyway the idea of putting more air in the exhaust was to reduce hydrocarbon and carbon monoxide emissions. As you are aware air cooled VWs like running a little rich to stay cool. The extra air was introduced near the exhaust valve to add oxygen to any unburnt fuel so it would fully burn in the exhaust system (after burn)

    The EGR was there to reduce oxides of nitrogen (there are a number of different ones). it did this by introducing some exhaust gas back into the inlet manifold under lite throttle (not idle or full throttle). Lite throttle (cruising) increased combustion temps high enough to make nitrogen (most of our atmosphere) interact with oxygen to form the oxides. The exhaust gas (which is already burnt) cooled the combustion because it took the place of some of the fuel. When the NOx mixed with hydrocarbon in the atmosphere and the sun was out another chemical reaction took place which was photochemical smog (brown haze).

    The carbon monoxide emissions is a result of incomplete combustion which is a tune and combustion camber design thing.
    If the fuel mixtures are to rich CO (and HC) will increase, if to lean HC will increase due to incomplete combustion and missfire.
    So back then CO and in some cases HC levels were stated in workshop manuals and under the bonnet and these could be checked with a gas analyzer. This was to guide the technicians to properly tune the vehicle and keep them within the acceptable emission levels (grams per kilometre).
     
    Last edited: Jul 18, 2018
    Mordred, syncro, Grantus and 3 others like this.
  13. syncro

    syncro Well-Known Member

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    8,893
    Location:
    Southern Highlands
    Different states had different pollution laws (ADRs). NSW Australia built delivered vehicles were injected from mid 1976. Most other states had twin carbs. Air pumps came on the imported VWs for NSW. Most people took the belts off.
     
    1500king and Mordred like this.
  14. 1500king

    1500king Well-Known Member

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    1,517
    Location:
    Adelaide, SA
    Good stuff here!. Yep, Air pump. I've only ever seen them on cars from 1978. Buses, Passats, Golfs, Toyotas, Datsuns....etc. I've seen EGR on cars as early as 1973/4, most with it all ripped off. VW bulletins certainly specify the "M" code option for smogged cars with egr, dual vac distributors, carbs with leaner jets, etc,etc. All from 1973-ish... depending on the bulletin.
     
  15. 1500king

    1500king Well-Known Member

    Messages:
    1,517
    Location:
    Adelaide, SA
    I am amazed it is still on there! Pumps air into the exhaust ports.
     

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