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zclocks last won the day on April 5 2018

zclocks had the most liked content!

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About zclocks

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    Seal Beach, CA
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My Cars

  • About my Cars
    75 280Z

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  1. Hey Motorman, Does the Fry's in SD look like it's going out of business? I went to Fry's in Fountain Valley a couple of days ago and the store is really empty. I guess Amazon and the other on line stores have really put the hurt on Fry's
  2. Thanks for posting my article. I've attached a photo of a random 240 clock , which is the one that Jeff has, and this is what causes most the 240 clocks to stop. I have worked on many 240 clocks over the years and it's always the same thing. If you add oil this is what you will end up with. If you try to clean things in place you can't do a very good job and you will damage parts. There are plastic parts in the clock (some plastic motors in later 240 clocks) which can be attached by several cleaners. I use only IPA (alcohol) which does a good job, but you need to scrub the parts to get the gunk off . The 280 clocks have a completely different design which uses plastic gears against metal. If you oil on these parts you can degrade the plastic over time. There is nothing in this clock that needs be oiled. The 2 main rotating components are metal against nylon. Nylon is self lubricating and it shouldn't be oiled . Again this clock mechanism needs to be disassembled and cleaned, not oiled. The main failure of the 280 mechanical clock is the circuit board. I do repair these and sell them on my web site. Anyone can usually repair either of these 2 clocks, it just takes time and patience or you can send it to me. Just my 2c.....Ron PS: The first photo is the 240 clock and the second is the 280 clock

    • WANTED
    • USED

    Looking for the coil wire bracket in photo. Please pm or e-mail if you have one for sale. Thanks....Ron


  4. View Advert 280z coil bracket Looking for the coil bracket in photo. Please pm or e-mail if you have one for sale. Thanks....Ron Advertiser zclocks Date 07/20/2019 Price Category Parts Wanted Year 0 Model 280z  
  5. FOUND SMOKING GUN!!!! I finally found the source of my miss and sometimes backfire thru AFM. With all the things I had done I didn't look at the spark at the plugs. So...... I removed the spark wire at each plug, plugged in a spare spark plug and started the motor. Each plug was firing, but VERY weak. To cut to the chase the ignition coil was the problem. Let me rephrase that....I was the problem. I remove and replaced the coil many years ago for whatever reason. The Primary side coil resistance is supposed to be 0.40---0.55 ohms, per service manual for the 75. The Fire ball I put in there many years ago was 1.6 ohms. This might not seem to be a big change , but when I replace the coil with a "Flame-thrower -2" what a difference. The new coil has a primary resistance of 0.6 ohms , but try and find a coil today which is 0.4 ohms is not possible. I know I have my OEM coil , but at the moment I can't locate it .BTW this new coil is used with the OEM ballast resistor. This is a good day!!! PS : I should give credit to a u-tube guy with a site called "Restoration for beginners". He seems to have good understanding of basic mechanics and after watching his segment on ignition systems, which covered coil replacement, he ran into the same problem with selecting coils. Oh yea his car is a 78 280z.

    • FOR SALE
    • USED

    For sale is a very nice 280z clock that keeps excellent time. The circuit board was rebuilt , mechanical internals cleaned , lens polished , set knob re-blacked and lamp replaced. Thanks for looking......Ron


    Seal Beach, California - US

  7. View Advert 75-76 280Z Clock For sale is a very nice 280z clock that keeps excellent time. The circuit board was rebuilt , mechanical internals cleaned , lens polished , set knob re-blacked and lamp replaced. Thanks for looking......Ron Advertiser zclocks Date 07/19/2019 Price $155.00 Category Parts for Sale  
  8. You may have just ruined the clock motor and the other bearing parts made of nylon and plastic. Most brake cleaners contain Tetrachloroethylene , ACETONE and chlorine all of which are great grease and oil removers, but detrimental to most plastics. Just a FYI

    • WANTED
    • NEW

    WTB clocks from 77-78 280z and 79-83 280zx . Please e-mail quantity and price. Thanks....


    Seal Beach, California - US

  10. View Advert WTB Quartz clocks WTB clocks from 77-78 280z and 79-83 280zx . Please e-mail quantity and price. Thanks.... Advertiser zclocks Date 07/17/2019 Price Category Parts Wanted Year 0 Model 280z  
  11. Hey Dave, I was going thru a few boxs of Z parts and found a 75 transistor Ignition. It's completely made by Hitachi . They were one of the big part swingers of the day. I'm impressed with the design and construction. Looks like the main power transistors were also from Hitachi. As soon as I can i'm going to install it and see if it makes any difference in my car. If not then I could have a spare or something else to repair.
  12. Dave, Yes, caps have a limited life and so do power transistors. No telling what material they used. If I can get a transistor unit I'll see about replacing the transistors and caps. Ron
  13. Yes, I should know better. I've seen so many corroded connectors on clocks that I just replace every wire /connector. The thing that fooled me is that the connectors didn't look bad, but corrosion is resistance. Thanks again for the input. Ron
  14. Dave you are correct there are 2 transistors in the control unit that are associated with the pulse to the injectors (FSM EF-51).One transistor is associated to injectors 1-2-3 and the other with injectors 4-5-6. I did this check with the 3 volt lamp as indicated in the manual and both transistors check out. This isn't an exact performance evaluation , but rather an overall output check. Funny I remember many years ago I had a lamp that was provided with a FI meter I purchased and no explanation of what it was for. I don't know what happened to it, but that was the lamp as mentioned in the manual. I also pulled the dropping resistors and cleaned everything including the connector contacts on both sides. All the resistors measured 6.5 ohms. After I reinstalled I checked that the power relay was working and there was battery voltage at the control unit pins for each injector. The car is running MUCH better and no backfire thru AFM. The drop outs are farther apart and very small compared to previously. I went back and retested with my Colortune unit and the visual blue flame is much better on cylinders 1,2,3. There are still some drop out or miss fires, but not as many. The intensity of the Colortune flame is much brighter. Cylinders 4,5,6 are unchanged, bright in color intensity and no drop outs. So, I think part of the problem may have been with the connectors on the dropping resistors or the control unit connector. What I am going to do is remove and clean all connections on the distributor, transistor ignition unit, and injectors. All my injector connectors were replaced about a year ago and I still have to replace the AFM connector. It looks good but the boot has deteriorated. I would like to dig into the transistor ignition unit and see what's going on there. I need to hunt down an OEM unit for testing. Anyone have a spare they would like to part with? I still believe there is a slight problem, but I think I'm on the right path. Thanks for all the inputs it's really helped. Ron
  15. I haven't swapped injectors, not my favorite thing , but that's just about all that's left. My car use to idle very smooth and had quick throttle response. I know there's a definite miss in 1-2-3. Could be the injectors not working correctly although they sound good . What are the chances that just 1-2-3 injectors are bad? Ok, thanks for the input and I will proceed with my quest. Ron
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