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Just wasting brain space on how many different EGR Exhaust Gas recuirculation systems are found on our Subies - particularly the older EA series.

When I first got my 84 Brumby it came fiitted with an API import EA81 complete with hydraulic lifters and some big metal can attached to the EGR port on the drivers side head. Measured about 80mm diameter, probably same high and was attached and connected at the head - went nowhere.

I also scored the original EA81 and its bits - can't recall much yet its EGR was different. I think they both had the EGR valve bolted to intake manifold.

Then there is the twin carb manifold -has a normal looking EGR valve at the back of the inlet manifold in the centre. Vacuum lines here and there - gives no trouble.

I have an EA81 with an EGR outlet at the top of the dizzy sides head, at back corner off #3. I think it simply fed to an EGR valve mounted at the back middle of the inlet carby manifold - just when I got it was feeding hot air to melt anything in its reaches - accelerator cable, pollution junction box etc ...someone forgot about it, failing to make it connect to the EGR valve nearby. Came with an invoice to suggest a dealer had it in its care

I think the most I have played with an EGR was with EA82T, feeds up from dizzy side head and into the EGR valve. Controlled with vacuum via solenoids and ECU. Supposed to work only below 45kph, at op temps and at about 1 to 10 inches Hg vacuum (light cruise).

Now, looking at stuff of TOONGA's pics in another post (link needed) the Brumby EA81 of at least 1988 onwards, does not have an EGR valve It uses a plate where EGR valve would go on all other EA's. This plate has a pipe fitting that takes in air from the pollution control things - big black jam donut sized black plastic thing, sand timer looking thing, and reed valve alloy unit. (Pull the reed valve apart, get confused which way valve goes back - look for a recess to take the screw heads - easy )


I find that on all inlet manifolds that have EGR valve mounting points, they have two ports behind in the inlet manifold casting, they'd be exhaust gas into EGR valve, and exhaust gas - out to then enter air fuel inlet stream below the carby. But on Brumbys with no real EGR valve, the EGR inlet port is clean as a whistle. Where you'd normally find an GR pipe off an exhaust port somewhere on or below the head is just a plateaux on the casting. The oulet hole behind EGR cover plate is sooty so can see it connects to inside the manifold under the carby .

Next, my latest import - the EA82 spfi inlet manifold, it has a normal looking EGR valve bolted in place, just gotta nut out some control system for it so it works at correct temp and speeds. Now, Tweety has my TPS, now I know why I wanted to keep it . Have to play with a normal EA82 mpfi TPS and make it work for idle on switch....

An EA82 mpfi NA I have also has a normal looking EGr valve with ECU control.

EA82T use normal EGR valves.

EA82 carby 11.86 make date also used normal looking EGR valve system.

So, summarising the diatribe above, the 89 onwards EA81 Brumbys used a unique to the rest of the EA Series system - more an air pump system that provides fresh filtered air from the air filter box into the non dizzy side heads exhaust port, not the other side and also fresh air into the inlet manifold via the normal EGR valve porting system under the carby - gotta wonder why only Brumby got this system and not EA82s of same era ??

Is it because Brumby has a commercial classification for pollution ??

Not gonna edit the above - found out L Series got same system as the later EA81 Brumbies ! Even found one in my junk (no surprise there )

Fuji calls it AI for air injection and half of the junk above is AI system, the other half is anti-after burn.

The anit-after burn is for high fuel mixtures on sudden decel with carbies and consists of the sand timer shaped thing feeding filtered air via the piped plate where EGR normally lives on the inlet manifold.

The air injection is the reed valve and pipe connecting fresh filtered air into just below the exhaust port. This is to "promote oxidation of HC and CO during cold engine operation.

So, looks like the later Brumbies at least do not have an EGR system at all , they only get it when an engine transplant comes along from non Brumby MY or other options and upgrade rules seem to be need to retain donor engines emissions - wonder if same rule applies to commercial veehickles like Brumbies ??

there you go boys and girls, I've learnt something