rclayton12

I just recently replaced my 260 style balance tube on my 73 240z with an orignal style 240 balance tube that didn't have the water lines and egr and emission stuff. The problem is that now since I have replaced the crank pulley and the balance tube, I used about half a tank driving about 40 miles. I used to average about 185 miles on one tank (even though that is not really good either). The car has upgraded to ZT S.U. carbs. So my question is why has my gas mileage gone down so much. Do I need to reset the timing, blance the carbs.. or should I go back to the other balance tube?? Please help. -thanks

So I need to take the valve cover off to put the crescent on there right? Will that scar it up or any thing?

Does anyone have any tips on how to tighten the crankpulley bolt down withought the car moving? Does any one know the torque setting as well? I sure do not want that bolt coming loose.

The entire ignition is stock, factory coil, distributor etc... The car had all of the emission stuff the 260z had, so it does have the 3 wire connection. I hope to upgrade the ignition soon, but havn't yet. Do not know what the deal is with the tach. I can hook up a ohmmeter and get flutuation in current if i step on the gas while the car is on, that is why I think I may have bad tachs.. don't know though.

Does anyone have a 3 wire tach. that they know for sure works?? I have a 1973 240z and cannot figure out what is wrong with my tach. I have the 3 wire it had on it, a 4 wire one, and a 280zx one, and none of them work. I get voltage from the plug under the dash, so I may just have 3 bad tachs. Is there a way to troubleshoot?? Thanks

My car is the 1973 240z. The car has one pulley designated to the air pump, one to the ac compressor, and one to the water pump and alternator. I gave the damper doctor a call and although he didn't have the exact kind of crank pulley i needed, he is going to replace the rubber inside that holds that third pulley on, and it also comes with the 3 year warranty. Thanks for recommending him.

Here are some pics

Thanks for the help. The part that came loose was because the rubber inside of it wore off, no damaged crank shaft or anything. I talked to a z world guy about the pulley. My car had the dealer installed AC, so they had a different pulley put on. They guy told me to just go with the two belt pulley and leave off the compressor and the air pump. The radiator fan, water pump and alternator would be on the 2 belt pulley. He recommended me just buy a new one because if I get one out of a junker, the same problem will happen later. Does anyone know any someone besides MSA that sells new ones because it is about $224 for theirs.

I was driving home one night, and my temp was over all the way, so I pulled over and the back part of my crank pulley was loose from the shaft part of it. The crank was spinning, but the part with my belt to my alternator and water pump was not. Does anyone know how to fix this, can I weld it back on, or if I have to replace it, how do I go about it. Also where can I find another one, mine has air pump, fan, alternator and AC compressor. -thanks

Yes came with replated springs, center linkage and everything. I have mounted them and have got it running. I need to get the timing checked because it is definately off. Does anyone have any tips on cleaning up the 240/260 balance tube?(clearing and jb welding all of the emission things) Has anyone removed the exhaust gas reticulation valve on thier z??

I have just bought a set of the S.U.s from Ztherapy for about $750 with the adapter for the air filter. They are going on a 73 240z that had the hitachi flat top carbs. How hard are they to install and what can I expect to encounter? anyone ever ordered theirs from ztherapy? How long does it typically take?

I have had one of my mag wheels crack, so I am currently riding on a black ugly spare. I only need one wheel, not all four. I was wondering if anyone has upgraded their Z wheels and would be willing to sell their old slotted mag wheels. The wheels on my car are 14X6, and are a brand " shelby cal 500 " . Thanks

I have a 73 240z with the 5 slot 14 inch mag wheels. I had some new tires put on last month, and the right front wheel was cracked. Does anyone have any spares that they would be willing to sell me? I only need 1 of the 14 inch sloted mag wheels, not all 4. Thanks, rclayton_12@hotmail.com

I have a 1973 240z manual trans, and I have 3 tachs that i am not sure if they work or not. One is the one that came off the car, the 3 prong tach, i also have a 4 prong from an earlier automatic 240z, and a tach from a 280z. Does anyone know how to test a tach to see if you can get any needle movemet with a battery or anything?

I have a 73 240z 4spd, and my Speedo recently went out. I was driving to school in the morning and all of a sudden it jumped around, then just went to 0mph. The cable that goes to the transmission is fastened tightly, there are no bad bends, but it does have alot of fluid on it. Also my tach does not work, it is a 3 prong. Where should i begin to troubleshoot it at? And my temp. guage recently stoped working, it just sits all the way to the left. It was working great and i do not know what is worng.

thanks for all the help!!, but the problem was that my positive battery cable was corroded under the two bolts, i replaced it and it fired right up. It was that simple

I have replaced the alternator about 4 1/2 months ago, and the car does indeed have oil. I have charged the battery and even switched it out and that is not the problem. Where is the neutral switch located at?

My '73 240z with manual trans was running great, but all of a sudden I couldn't get the engine to turn over at all, it has happend once before, but i got a friend with a honda s2000 to jump me off just fine. I have replaced my started and cylinoid, and the batter is good please help!!!

I think I may have a vacume leak, where do I begin to check, and how do I tell. The car seems to cut out and the RPMS will jump up occasionally. Also part of the problem may be that spark plugs in cylinder 5 and 6 seem to foul out quickly, what do I need to adjust. Also would a valve cover gasket leak cause this? -73 240Z, flat top carbs, monza exhaust, omni spark wires

The plugs in 5 and 6 were wet black. I have brand new Omni spark plug wires, month and a half old air filter, modified down pipe and free flowing Monza exhaust system.

I have a 73 240z with flat top carbs. It feels as if the car is only running on 5 cylinders. It idles really rough. I took the spark plugs out today and the plugs in cylinders 1-4 looked normal, but in 5 and 6 they were really black. Is it running rich? The manual says to turn the idle mixture screw counter clockwise to increase the mixture. Is that correct? Also I have replaced all spark plug wires, and sparkplugs, should I check the distributor cap?

Stock ignition and stock distributor. Only thing new are wires and split fire plugs.

Yes, I have flat top carbs. What the engine does it when I first start it up, it pulls reall strong, then it seems as if it cuts out. Some times when I apply light throttle, it will cut back in. But most of the time it is underpowered. It seems like only half the cylinders are working. Sometimes the engine all of a sudden "kicks in", and throws me back.

I have a late 73 240z, and the engine sometimes surges. It is majorly underpowered, and seems like its only running on about half the cylinders. We replaced the fuel pump, had the points checked, replaced the air filter, and replaced the spark plugs and spark plug wires. The engine ran great for about 2 months. It started surging, so we checked and readjusted the valves (cold), and it ran perfect for about 2 weeks. I didn't run the engine over the weekend, and now have the same problem happening, the engine surges, and most of the time is severly underpowered. I have balanced the carbs. Should i try to readjust the valves hot? What should I do?