<>'73 240Z SU Carb Choke Adjustment. <>Hi ZDoc,. I have a 73, and the chokes constantly need adjusting and lubing. I have been taking it to the shop, but this is an expensive semi-annual repair. How can I avoid this cost and do the work myself.. Where can I find the adjustment procedures, and if there is not something printed to view, who do you exactly go about lubing and setting the chokes?. Thanks a bunch!!!. Doc replies:. Hi Tom,. Doc here, you sound like you have some mechanical background and then you should be able to facilitate the repair. First you need to replace the nozzles from the bottom of the carbs. Carefully mark the position of the tops and remove them taking care to treat the parts separately. with the bell and spring off carefully clean them with Berryman's B-12 carb cleaner, watching out that you are NOT smoking or in the area of a flame. Watch out for the paint!. Next carefully remove the slide that has a pipe sticking up and the needle on the opposite side. Watch out to treat the needle with care so that it is not bumped or dropped, since it is exposed and subject to bending and damage. There is supposed to be oil inside the the top pipe so when you turn it over it should not surprise you. Thoroughly clean it with carb cleaner. Look at the manuals to check the needle reference height for the initial set up. If there is wear on the needles, then order them from the Nissan Dealer Parts Department too. A special note here about the rubber hoses that are linking the float chambers to the nozzles for you is that ONLY the factory hoses (costly) will last, so DO NOT buy any other ones, or use the ones that come in the generic carb kits! The MTBE in the fuel will destroy the non factory hoses in short order and fuel will be pumped out onto the hot exhaust manifolds and the Great possibility of Going Up in Flames!. Make sure that the choke cables are not sticking and are free in operation. All this operation is possible on the car with the air cleaners removed. Install the new nozzles and note that they are green, and that is the teflon coating that will stop the sticking problem. The hoses are straight forward and the reassembly is in reverse order. The cable adjustment is more complicated and the carbs need to be synched and balanced too after the parts are removed, but not critical if you do not disturb the bottom wheel adjustments, since the nozzles just drop out the bottom when the little screw is removed going through the linkage,and then into the black part of the nozzles. The oil that needs to be restored in the top tube is ATF in the winter and motor oil in the summer.. Where are you located? I have many ZONC Members make an appointment and come to Mariposa (just outside of Yosemite) to get the carbs set up and then have the power potential that seems to be missing all along.. The other thing is that you need to have the valves adjusted at every 12-15 thousand miles, and that the ignition has a major performance factor in the total performance picture of your "Z" car. Some 1973' have electronic distributors and some are still points and condensers. All have bushings that wear and vacuum advances that are subject to failure with age of the components. These are things that are many times missed by the untrained Technicians that have been dealing with fuel injection and electronic ignition systems for many years. Knowing the fine points of the engineering in your "Z" seem to be limited to a very few.. Are You a ZONC Member? Z OWNERS OF NORTHERN CALIFORNIA! JOIN ZONC! Ask me How!. How did you find me?. I hope that this helps you..... Doc Kanarowski.