zclocks

I was reading these posts and thought I would throw in my 2-c worth. From my experience the OEM 240 clocks are not sensitive to voltage but are very sensitive to temperature and contaminants(oil,dust, metal fatigue). I use two different power sources( power supply and car battery) and I have not seen the difference. What I do see is the minute the temperature in my shop drops or rises 20 degree the 240 clocks start to change. The OEM clock winds the main spring by a small motor that keeps constant pressure on the spring which drives the gears of the clock. This is all good as long as the spring is new, the gears are clean, and the temperature is constant. The bigger problem is that after 40 years all the moving parts are VERY worn and it's hard to get the clock to deliver better than plus or minus 10 min. per week. Another variable is everyone seems to think oil is required, it's not. This is a short term fix and only complicates the problem. If you really want to make this clock accurate and reliable you can. What it takes is to disassemble every part, clean, inspect, replace the worn items, and reassemble. NO oil or lubricant. Also, this should be done on a yearly basis. I know this is excessive but this clock is just like your grandfathers pocket watch or wall clocks. Grandfather clocks are accurate and had many moving parts but they were all cleaned inspected, and adjusted yearly for accuracy. The hybrid clocks, 75-78, have a zener on the power line which regulates to 7 volts so power is not a factor. The quarts clocks have only 4 moving parts that are not constantly moving like the 240 clocks and there is also a zener to regulate power to 7 or 8 volts. Ok, enough and I assume I'll get a lot of flak from this post. Ron (Zclocks)

Zclocks only takes one week for refurbishment and has a 6 month guarantee!!! -Ron (zclocks)

The Zclocks website has been updated and two new articles have been added. 1)" How to identify your clock " 2)" Rally clock identification" The two articles should help when looking for or asking questions about these clocks. Thanks ...Ron @ Zclocks.com

I couldn't help but chime in with my 2C. Contrary to public opinion I do have 99% of the parts for the oscillator, including the ckt bd . As soon as I perfect the last two parts I can build a complete oscillator from scratch. Also, I have lens, those hard to find knobs and knob screws . I'm not into selling parts but use these to refurbish clocks. The Oscillator is a lot more than just resistors which usually don't go bad. This is 40+ year old TTL /discrete technology and usually needs a lot of TLC, especially as fragile as this clock is. Another problem is TIN whiskers, look this up as to lengthy to describe here, which is a anomaly of component leads that were not SOLDER coated. This is a bigger problem than anything else in my mind. As my wife says "you can improve a princess a lot easier than a beater". One of the misnomers of the two knob rally clock is that it draws excess battery current. This shouldn't be a problem as the standard clock draws only 12-15mA and the 2- knob rally 30-33mA. If your drawing a lot more than this then you have another problem. I have a 2-knob rally in my car and the car is lucky if it gets started once a month. I've never had a low battery problem and the car has other devices that draw a lot more than the clock. Also, excessive motor noise is coming from a worn gear/bearings in the housing. This part is not available anywhere, here or Japan. This is unique to this clock and no substitutions are allowed. Only the original material used is acceptable or you will ruin the mating gears. I make the bearings and working on making the gears. Just my 2C worth. Ron

geezer, Not sure if you can use SN to determine early or late box. SN 2032 was the later box and I have records that show a SN 2092 was an early box. In addition I have worked on a SN 0013 which was a very early box. It seems to be consistent that if the wire harness has the 6 pin plug that all the ones I've seen are the later boxes. I believed that JECO started producing the later boxes in 74 . I worked one box that had a 240 bezel on the clock housing with a 6 pin connector and another clock set that had a late 260/280 bezel on the housing that had a 6 pin connector. The connector seems to be the tell because it showed up on the late 260 and went through 78. just my 2C. Ron

Geezer, I just worked on a RC that had SN 2032 on the osc box. Ron

Kats, If you still have the late box I could look at it and see what I could do. If I had one of the late boxes for a month or so I might be able to figure out what the mystery parts are that are not available. Let me know....Ron

Kats, The oscillator boxes are interchangeable with either early/late RC clocks. So, if you have a clock and your looking for an oscillator any one will work. However, the parts for the later osc box were manufacture (JACO) unique and no longer available. Ron

Mike, I have pictures of your before clock and osc., see attached. Ron

Make sure to change your fuel filter after you complete rebuilding the gas tank. Ron

draztik280, The quartz clock doesn't have a manual adjustment. If the clock is not keeping the correct time it needs to be rebuilt as it will soon stop all together. You should have looked for my post I wrote several years ago about OILING your clock...don't do it! These clocks we never oiled or lubricated by the manufacture and for several good reasons. Oil will only bleed out on to critical areas and finally stain the clock face and plastic parts. Your clock needs to be rebuilt. If your interested and having your clock refurbished correctly please see my web site at: www.zclocks.com Ron

Sorry for the delay in answering all the e-mails but my web site had a New Years Problem :stupid: Currently the site is up and running so please feel free to e-mail with questions and hopefully clock orders. Thanks and Happy New Year. Ron Ron@zclocks.com

Zedyone, Thanks for the great complememts. I really try hard to provide the best service possible for the Zcar community. Ron (Zclocks)

Will, Good work and you are right on. I have a schematic and part numbers from most of the parts,but you have other problems to overcome. The motor is obtainable and it is dc not ac. Gears are another problem and the bearing for the motor or other motor need to have a 14mil ID to work and maintain alignment with corresponding gears (I make these). Patents are still in place and Citizens and others are not willing to let them go(I've already tried). Also most of the parts were subcontracted and not made by Citizen. Citizen just put their name on the product. You can and will ruin the tuning fork if you don't know what you doing. Just removing the ckt board from the housing can damage the fork. And lastly the media that attaches to the fork is a 2mil ribbon. You will have to have micro soldering or wire bonding tools (epoxy will not work). Interested to learn the outcome... zclocks

Buzz, I'm with Arne on this one, find a new installer. You could install a radio 11 inches deep in the space you have on the 260. You need some one who isn't affraid to get creativ , build a mounting bracket and install whatever you want. Gads....I have a Clarion in my 75 and it has an amp hanging off the back of the 6 inch radio that adds 4 additional inches. What stereo shops want to install is something someone else has worked out so they can do it quick and charge max $$. Crutchfield is very good but their only a reference/starting point. If the radio is a problem with maxium room I hate to think what will happen when you start installing speakers in the doors!!! That's another one every source says can't be done. I have 6.5 inch 3-ways flush mounted in my car with no problem. If you know how and arn't affraid to experiment you can custom fit anything. ....ZC

If the clock and control unit are working and the clock was in good shape it would be worth something. However, if someone has tried to repair the control unit and damaged any of the critical parts it's worth nothing. Parts for these units are not available and you can't make them. Zclocks

Matt, Make sure the the throttle linkage is not sticking or hanging up. You can check this with the engine off by slowly working the linkage.The linkage should work smoothly when opened by hand and should return to a completely closed position. Also, the throttle valve in the throttle body may be sticking due to deposit built up. Ron

Dave, Not sure why you asked the question about accurate time for the quartz clock. In the previous post Jon has a mechanical clock and the time/accuracy there is completely different than the quartz. The stock mechanical clock has accuracy problems and and the best you can do is minimize the problem. The owners manual for the stock 240Z clock suggests you "set the time daily" for accuracy? They knew there was problems. Ron

Dave, The quartz clock is crystal oscillator controlled. I check the accuracy against the standard I use, but the real accuracy is how well you can set the clock time. Using a time standard and different hands (for accurate measure) I have determined the quartz movement to be within one second per month(again this is my standard). There is a provision to adjust but if the solid state components are within tolerance there is no need to adjust. Also this is the standard quartz clock mechanism that Datsun used in their quartz clocks which was supplied by their subcontractor Kanto Seiki. The answer to your question is no I do not adjust the accuracy before I ship but I do check the accuracy. As long as the clock supply voltage is 10 vdc the clock should perform as described. The quartz clock accuracy is as designed by Kanto Seiki, no jewels and unadjusted.Oh yea I forgot, all my clocks are LAB TESTED. Hope this helps.....Ron

Jon, Good going. Make sure you test your clock for several days by watching the time and making the speed adjustment if necessary. It's almost impossible to adjust the time(fast ---Slow) if the clock is in the dash. If you can't find you bracket let me know as I think I have a 100 or so laying around. Ron zclocks.com

Gary, These (the early two knob) clocks are very sensitive and parts are not available. I've worked on a hand full and their all different. First you need to determine if the motor in the clock is working. The way you do this is connect it to a battery and you will hear the motor hummmmm. If it doesn't then that's problem number one. The clock is just a motor and lots of gears. The real timing, accuracy, and control is in the control box. Whatever you do don't play with it as you can screw it up beyond repair. To be very conservative I have seen the two knob rally clock go for > $400 so make sure the repair service you pick is experienced and has worked on this particular clock. For the rest of everyone who's asking about the control box(unit) , YOU CAN"T BUY ONE and their NOT AVAILABLE. This unit is 39 years old and very unique. Without going into a lot of detail this is an RF engineer's nightmare. To be very honest most of the early rally clocks I have worked on I have been very lucky to fix and I only say that because there are no parts and if something breaks you have to build that part(if you can) from scratch. So like I said earlier, pick your repair service carefully or you could loose the clock(early two knob) entirely. As far as the single knob clocks goes I can service and refurbish without problems. Currently I have one on eBay for sale... Ron

The clock on e-Bay is not the one as offered by Datsun on the 70-73 zcars in japan. This clock does NOT have a control box and the bezel on the rally portion is fixed. Also the early rally clock (70-73) has two knobs on the face. The one on eBay could very well work, but it better have been rebuilt or it won't be working long. The clock is still a nice clock and different from the standard clock. If you want to see what this early clock looks like it's on my web page (zclocks.com) or see the attachment. Zclocks

It's always hard to start something new as mentioned in the previous posts.The ARC welder is for heavy metal and the Z body is very thin. Not mentioned is that you can not weld rust. If your a very visual learner then take a class at the local community college. You'd be surprised how fast you can pick up the art. You'll learn that arc is only one of the many welding types (gas, Mig, Tig...etc) and going through a class you will see it all. ZC

Motors in the 240 clocks do go bad. They are very delicate and are not possible to repair. I'd say most of the time the clock simply stops because of the sludge. Ron

Mike, I would think it's best to keep the clock running.