poopypants720 Posted January 3, 2015 Report Share Posted January 3, 2015 When I got my '81 720 with a Z22, it wasn't running, was missing the front grill and valence, likely had minor front end damage at one point with the make shift tube bumper and different color fenders and a fabbed battery tray.... It had Rancho shocks, a 2" body lift from a kit, and a weber 32/34 on it(the only aftermarket carb ever made available for the truck that's still CA legal)... So the previous owner knew what was up for the model and had some know-how in ways to improve it, but keep it smog legal... Buuut it also had various parts in the bed that were obviously all off of an '85 year model that I guess was scrapped shortly before I saved the '81 from sitting in the desert another 5 years... yet I find no obviously '85 parts installed on the vehicle body/interior/engine(with this one possible exception)... Sooooo... With all this, I have an odd situation. I have a Z22 motor that looks completely stock... had an owner who went through the trouble previously to maintain smog legal status... but have had obvious front end repairs and other year truck parts in it's locale... no smog stickers under the hood either... And basically has an exhaust configuration that I can't seem to confirm was actually ever produced! As can be seen in the photo above, the engine bay pictures above was right after I purchased the truck and didn't even touch it yet, just towed it to my place on a flat bed trailer, and there are no air induction tubes coming off the front of the exhaust manifold or from the front of the air cleaner! Not like it's plugged on the manifold either n this is some random air cleaner, it's cast with no option for AIV, no O2 sensor(usually eliminates possibility of coming off a newer model), just the EGR tube outlet on the back... Since this picture I've added Doug Thorley headers with capped AIV options on the front of the headers, which further leads to the confusion for the Tech come smog time... even though they too are E.O. numbered parts supplied for multiple configurations of smog applications from the '81 z22-> '86 z24.... Does anyone know if the vin would contain make/model/option info for our trucks that could help ascertain what SHOULD be on this vehicle and if this is even a possible factory configuration or just snagged off of another vehicle? I would like to be able to visit discount smog shops in the future and they always require more documentation if anything conflicts with their own book... which I've also found discrepancies with in the past, but without documentation, can't prove to then the legitimacy of my configuration being stock... Any help guys? Quote Link to comment
xsdg Posted January 3, 2015 Report Share Posted January 3, 2015 VIN decoder: http://forums.nicoclub.com/datsun-nissan-720-vin-decoder-guide-t587543.html Quote Link to comment
datzenmike Posted January 3, 2015 Report Share Posted January 3, 2015 I don't think a 32/36 was ever smog legal in California so if you were told that, I think it's wrong. Your truck has to pass a visual inspection (before you even get to the test itself) and have every emissions part on it. Original carb, warmed air from exhaust, the air induction tubes tubes, cat converter, valve cover hose connected, all vacuum lines, the list is endless..... You can't use later emissions parts unless it's the same part. That air cleaner may be from an '85 and on which (I think) did not have the air induction tubes and one way reed valves in it. Likely the exhaust manifold was swapped too. This won't fly and the PO's poor attempt to 'de smog' the truck. Before wasting any time on it go to the emissions station and talk to someone about it. Find out what you need first. Maybe the parts are there in the back. Quote Link to comment
poopypants720 Posted January 3, 2015 Author Report Share Posted January 3, 2015 I've passed smog twice already with my current configuration... So while the visual inspection usually gets you caught up, I've had some shops not care as long it produced acceptable numbers... their shops just cost more to test throug. N the carb is a weber 32/34dft9a and as I mentioned, definitely smog legal... http://arb.ca.gov/msprog/aftermkt/devices/eo/D-133-8.pdf As for the manifold and air cleaner... I too assume it came off the 85s Z24 motor... which sucks... but I've seen a diagram even with an '82 z22 that had no air induction system n so I believe there is a small possibility for an '81 model with the same... Wish I had the old manifold still to see if there were any identifying marks... Mike, starting in '84 with the Z24, didn't they add an 02 sensor though? Cause that "original" manifold pictured had no sensor, just the egr coming off the rear. Quote Link to comment
datzenmike Posted January 3, 2015 Report Share Posted January 3, 2015 ALL Z24 California engines had the feedback carb with O2 sensors. I thought some late Z22 did also but apparently not, just the EGR at the back. Hey anything is possible and some places don't do a visual but a certified emissions testing station will. I have no doubts another could and would pass, didn't know about the 32/36 exemption though. Still should have the air induction valve on it... the L20B had it and all Z22s. Only stopped using them in '85 and maybe that's an '85 exhaust? Quote Link to comment
poopypants720 Posted January 3, 2015 Author Report Share Posted January 3, 2015 VIN decoder: http://forums.nicoclub.com/datsun-nissan-720-vin-decoder-guide-t587543.html cool resource, if you have a 17 digit vin... still wouldn't show me anything necessary like Ca, fed smog applications installed on the model... Quote Link to comment
poopypants720 Posted January 3, 2015 Author Report Share Posted January 3, 2015 ALL Z24 California engines had the feedback carb with O2 sensors. I thought some late Z22 did also but apparently not, just the EGR at the back. Hey anything is possible and some places don't do a visual but a certified emissions testing station will. I have no doubts another could and would pass, didn't know about the 32/36 exemption though. Still should have the air induction valve on it... the L20B had it and all Z22s. Only stopped using them in '85 and maybe that's an '85 exhaust? Sorry Mike, not being rude, but you keep reading quickly over it... its a 32/34 dft 9a, not any type of 32/36! But again...the pictured exhaust had no O2 sensor, which would exclude the possibility of being an '85 manifold, right? I wish I could go back to a dealership and just all possible configurations for my model year! But all they will have now days is an "updated" manual that likely excluded "unnecessary" or "obsolete" information... Did ANY 720's with Z22 OR Z24 come with no air induction tubes, no O2 sensor and only an EGR valve? If so what model year? Again... I'm pretty sure I've seen documentation for this configuration on an '82 Z22... but didn't photograph the diagram/corresponding description... Quote Link to comment
datzenmike Posted January 3, 2015 Report Share Posted January 3, 2015 Sorry Mike, not being rude, but you keep reading quickly over it... its a 32/34 dft 9a, not any type of 32/36! Did ANY 720's with Z22 OR Z24 come with no air induction tubes, no O2 sensor and only an EGR valve? If so what model year? Thought you here writing it down wrong... :lol: I have no info showing the Z22 not having the air induction tubes, non California had one tube, California ones had two tubes) even the '80 720 with the L20B had one. They are missing on the '85 Z24. As to the EGR all 720 gas and diesel engines had this. Quote Link to comment
poopypants720 Posted January 4, 2015 Author Report Share Posted January 4, 2015 Is it possible for an 85 without air tubes to also have no O2 sensor? Quote Link to comment
datzenmike Posted January 4, 2015 Report Share Posted January 4, 2015 All California Z24s from Nov '82 and all Federal Z24s from the '85 model year on had O2 sensors. This means the Federal '85 had the feedback carb until April when they switched to TBI... also requiring an 02 sensor. Quote Link to comment
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