Nismo49

Hi Guys, I think that the previous owner told that he was using ATF in the dampers. The article that I read from Dave's website resource suggested 20W-50 for worn carbs as a third choice after ATF and 10w-30. I have some 20W-50 oil on hand ...will change it out and try that first before I get into changing the settings. Its about trial and error and learning....I have little experience in setting SU carbs. Thank You to everyone that responded..really appreciate the sugestions and recommendations. Will keep eveyone posted on my progress. Dave Nismo49

Hi Dave, I checked out the website and found many references that will be helpful. From what I have read so far...Ihave a lean condition or an air leak as others have mentioned. Really appreciate your references. Thanks Dave

Hey, I have been having some trouble my SU Carbs Bogging out. Help! My 1973 240Z with Round Top SU's is bogging out and sometimes stalling on acceleration with low engine RPM's. Pulling the choke on helps to aleviate this condition while accelerating up to highway speed. The engine runs great driving at higher RPMs (ie) 60 - 80 mph....or higher when the road is clear....it runs up to 120 mph...tail wind on nice level highway. When I slow down to make a turn and try to accelerate after making the turn, the engines sputters and boggs untill I pull on the choke and then it will hook up and accelerate smoothly. The engine sometimes back fires, boggs, coughs in this situation. The other strange condition is the engine will run reasonable smooth with the choke fully on while at highway speed..one would think that it should run rich and sputter and bogg out..other than stinky exhaust and some smoke, it runs fairly smooth. I have installed a new gas line filter, used some carb cleaner and this bogging issue still exists as before. The engine also is hard to accelerate from a standing stop...it quite often stalls when taking off from a stop. Pulling on the choke most often aleviates this problem. Another point of interest is that starting cold takes a lot of cranking to get it to fire up. My 240Z is an automatic...I have heard that the jets are different for the Automatics. Holding the accelerator pedal to the floor helps..and the choke fully on....it will take up to a minute of spinning to get the engine to fire the first time. Usually takes another 2-3 times on the starter before the engine will remain running with out stalling. The engine takes about 3-5 minutes to warm up and smooth out at idle. Starting hot usually is perfect..it will fire on less than one turn over if the engine has been shut off for up to an hour. PS: Previous owner had a complete new OEM SU Carb Kits installed less than 4 years ago. 3000 Miles since carb kits installed. I am looking for some advice on where to start making adjustments or service recommendations. Thanks Dave NISMO49 1973 240Z - 98% Original Documented California Car 110 Red - Original Paint Automatic Transmission 42,000 Original Miles