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Thread: Dead cylinder #3! Ignition or Fuel?

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    Z maiden Jennys280Z's Avatar
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    Default Dead cylinder #3! Ignition or Fuel?

    Spark plugs have 60 miles

    The #3 plug came out looking brand new.

    I've pretty much ruled out some culprits below:

    Ignition coil: Wouldn't effect only one cylinder 100% and other cylinders not at all.

    Distributor: All tune-up parts almost new. Distributor cap metal contacts show the same pasty white surface wear indicating it's operating correctly
    even for cylinder #3 i.e. they all look identical.

    Spark plug wires: Almost brand new NGK set. Tested resistance on #3 wire as 5,980 Ohms which should be fine especially for a wire 2+ft long.
    Spark plug: Looks like it never even fired...unless it's been firing in a cylinder with no-combustion (no fuel) in air only. The center electrode
    does look dark and glossy. I thought it was wet with gas when I first pulled it out, but it was dry. I don't have a new plug to compare it to exactly.

    No odor or substance on the plug besides a very weak gasoline smell, if that. No oil in the cylinder, no antifreeze or antifreeze smell, no gasoline in the oil, no signs of any strange shorts or arcing inside the distributor, cap, wires, engine or plug. Everything in the ignition circuit looks fine, and I never saw any sign of spark blowing out or grounding improperly (at night, etc). So the inspection of the ignition system suggests that it's not an ignition problem. I've verified spark at the wire with a timing light too. I'm too scared to pull the end cap off the plug with the motor running to know for sure, Ha!

    Cylinder #3 compression is 140+PSI in a COLD motor which rules out any mechanical problem (rings, valves etc.)

    A few years ago, I did clean the fuel injector connectors. Since then I've only put about a hundred or so miles on the car. If it's possible for a spark plug to remain looking 99.9% brand new when firing in cool-ish air with no combustion, is it possible to plug the injector in backwards and thus disable the injector completely and still have this phenomenon with a plug that was sparking the whole time? The #3 injector wire is a bit longer than some of the others, there's a bit more "slack" in the wire (a bigger curve) and it's not discernable whether the wire got twisted or that the plug was installed upside down. Is this connector keyed (does it prevent one from connecting it wrong)?

    A webpage from AtlanticZ says that the +12V end is always closer to the front of the car. It doesn't say how to distinguish one from the other. The new pinch-style connectors look nice too
    http://atlanticz.ca/zclub/techtips/i...ors/index.html

    I'm at a loss. The only other possibility I can think of is a defective spark plug (which seems like such a remote possibility it's not feasible) but is there anything else that could be causing this that I'm not thinking of?

    The car seems to be running good and even smooth at idle although it idles too low until it fully warms up. Starts immediately, fuel pressure is steady in the mid 30s. A hot motor has a 1000 RPM idle. Presuming it's running on five cylinders (which I have to do looking at the plug) (6/5)x = 1000RPM; x = 1200RPM implied idle speed with all six cylinders. And this kinda implies that I've raised the idle speed adjust high enough to compensate for a dead cylinder at idle.

    I don't want to run the motor again until I have a gameplan. I have a stethoscope and intend to listen to the injectors for the first time in a few days hopefully after some direction here? I understand I'll hear a clear buzzing sound when the injectors are opening. I'm skeptical a spark plug can come out looking this brand new firing for 60 miles without fuel. Or if someone here with more experience can verify that it's indeed possible that the ignition is fine (based on all evidence) and that it's simply a lack of fuel and combustion, I will pull off the injector connector and plug it in opposite of how I did before I start the motor again.

    I hope I didn't fry the ECU or at least that circuit to the ECU by wiring it backwards by accident.

    And if the problem is ignition, would all of the unburned gas really be going out my exhaust valve so perfectly like that, and not getting in my oil, without getting on the plug itself for that matter? I don't have the experience to know either way but I want to fix the problem without wasting too much money. Just collecting all my thoughts, I'm thinking this is a fuel problem more and more. My gut is telling me that a spark plug firing in relatively cool air with no fuel will look brand new for more miles than I put on it.

    Previously to this problem, or to at least to knowing about the problem, I tested the injectors at the ECU pinout and they were all showing very close to battery voltage. My battery is usually under 12V (down in the 11s) even a day after I drive it. I've either abused the battery by not regularly starting the car or I've got a drain somewhere. And not to risk stating the obvious but the injector is not leaking any fuel. I'd need even more help if it was lol I use Chevron 93 Octane with Techron, have treated the gas with Seafoam and in other tanks other injector cleaners prior to that, if that would make any difference to a physically clogged injector. Plugs are NGK BPR6ES

    Thanks!
    Jenn/Sean
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    Last edited by Jennys280Z; 08-10-2014 at 10:21 PM. Reason: paragraphs and neatness

  2. #2
    It's awesome bartsscooterservice's Avatar
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    You can put the spark plug in the lead hold ( or put ) it against some metal part of the engine and check for a clear blue spark when you turn the key. I think it's the injector that's clogged, or the injector is not getting voltage to open up and let fuel pass it into the combustion chamber. Maybe you need a set of new injectors ?
    HLS30 32581, 5/71 Matching numbers

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  3. #3
    Registered User EuroDat's Avatar
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    The RPM is always the same. You don't need to compensate for a dead cylinder. The tacho gets its signal from the coil negative. Its the same trigger the ecu gets to tell it what speed the engine is doing. The only way it would read 1/6 slower is if the coil was missing a pulse on number 3 spark plug. I would check the plug like Bart mentioned to be sure, but it sounds to me like an injector problem. It could be a number of things, blocked injector, injector coil open circuited, injector dropping resistor or wiring to injector open.

    If you have a fuel gauge in the system reading the pressure you can do a simple test on the injector to see if its working or blocked. Disconnect the injector plug and use 9 volt battery to activate the injector. If the pressure drops, you know its opening and it is not blocked completly anyway. You can compare the rate of pressure drop with one of the other injectors to get an idea what is normal. You might need to run the car between tests to build up pressure reduce the chance of flooding. Dont use 12 volts to activate the injector. They normal see a lot less voltage (around 7 to 8 volts average) during pulsing.

    You can also do a bunch of tests in the FSM to varify everything is working ok.
    Chas
    Last edited by EuroDat; 08-11-2014 at 01:32 AM.
    Chas
    5/77 280Z HLS30 403100 with some modifications
    Original colour: 305 Light Blue. The PO changed it to Red

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    Registered User madkaw's Avatar
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    Got to be an injector issue. Boy you will like your car when you have all 6 cylinders running- lol.
    You need to correct hour charging/battery issue Asap. Low voltages can lead to ECU or other electronic problems
    Steve
    71 240z,bw-5sp 2.4-40 over,balanced,e-88,big valves,ported&polished, stage2,header, triple Mikuni's 40's
    3.90 Subaru STI LSD

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    Nova Scotia,Canada,Earth Blue's Avatar
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    Usually it is the wiring and the connectors rather than the injector.

    Try swapping the injector connections between 2&3 or between 4&3 to see if the problem moves. (There is enough slack in the wiring harness to the fuel rail to do this). This trick is a quick way to determine if it is a problem in the harness/connector or the actual injector is dead.


    A good cleaning of all electrical connections in a Bosch EFI system is a wonderful treat to your car.
    There is scarcely anything in the world that some man cannot make a little worse, and sell a little more cheaply.
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  6. #6
    Z maiden Jennys280Z's Avatar
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    Update: Sounds like the consensus is a fuel injection issue. I have to agree with this. No evidence of ignition issues, and after all, if the plug wasn't firing and the injector was functioning, I'd expect at least some gasoline on the plug, not a bone-dry-new one like that.

    Looking at some old notes, when Jenn was cleaning the injector connectors she broke a small piece of plastic off of the rim of the #3 injector connector. It must have been just barely hanging there with a spot of glue or else it wasn't completely broken off yet. The instant I touched the metal retaining clip with a tiny screwdriver the piece of plastic went flying and landed on the heat shield. At least when things go flying in these old cars we have a reasonable chance of finding them. Plastic or rather the lack of it is another one of the benefits of these older cars, guess I can't escape it all the time unfortunately. But would something as simple as this cause a total malfunction of the injector? And I'm guessing from the replies it's impossible to plug these things in backwards?

    Seriously doubt something like this really cause a total injector failure? The connector seemed to be plugged in normally and held tight by the clip; I would think this wouldn't make any difference. Just a strange coincidence... The contact surface of the connector itself is probably looking a lot greener than it should. The male connectors on the injector itself don't look too bad.

    I was rigging up some wire on a 9V battery but maybe I'll swap two nearby harness connectors instead. If the problem moves to another cylinder it's the wiring/connector and if it doesn't it's the injector itself. I've never listened to injectors with a stethoscope before so I don't know exactly what to expect to hear...hope it's easy enough to be foolproof. Pulling a brand new looking spark plug out of cylinder #2 or 4 would be the backup way to tell if I'm stetho-challenged.
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    Registered User S30Driver's Avatar
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    The broken plastic where the injector clip goes is not causing your problem.

    Blue's injector connection swap is the way to go to isolate the problem.

    If you don't have a stethoscope, just use any rigid handy device - a long screwdriver, snowbrush handle, and hold it to your ear.
    You will hear the injector CLICK when it fires.
    1977 280z 06/77

  8. #8
    Z maiden Jennys280Z's Avatar
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    I'm going to swap connectors #2 and #3 which look like there's enough play in the wires to swap them. I wired up a 9V battery to test with that real quick but I'm going to run the motor with the swapped connectors first before I do anything else that may put gasoline on the spark plug and possibly muddy/confuse my results. So I assume either there will be a pristine dry spark plug coming out of #3 or #2. And hopefully neither because I just cleaned the connectors thoroughly with some sandpaper and some Caigs D5 on the male side and a wire brush and Caigs on the female and they're looking better now. #3 is pretty hard to reach, and even see with the fuel regulator and plumbing in the way but it's hard to think that just cleaning would make the difference between a completely dead injector and a normal one. So I doubt I'll luck out like that, and I'm not really gung-ho about actually fixing this problem ourselves whichever one it turns out to be. At the very least I'll diagnose it and we'll have a handle on what needs to be done.

    I'll use the stethoscope too while the motor is running to try to hear who's not clicking between #2 and #3.

    To answer one of my questions above, the connectors ARE keyed. It might be possible to plug them in backwards, but it'd be obvious because the top side doesn't look anything like the bottom (though the two shorter sides are visually the same) which is hard to tell until you actually take one off. The bottoms have most of the plastic cut off to fit along the curved surface of the injector.

    I see new injectors are $380 at MSA, and it's recommended that all six get replaced together. New connectors are also similarly priced. Labor would probably make this easily a $1,000 job no matter what parts we need. So many pros here but I doubt you'd have the patience for a hundred bad questions if we attempted a DIY. Another problem is I don't know any pro mechanics I would trust implicitly with this job. There's a Z specialist across town but I told them what year my car was and what problems I was having and they didn't even want to touch it. Fuel injection and no scanners? Eww Yuck!! It seems too many real mechanics are spoiled with OBD2 now. A Toyota specialist nearby didn't even want to look at our third generation Camry with OBD1. He actually implied on the phone that I just get a new(er) car.

  9. #9
    Registered User EuroDat's Avatar
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    If you are thinking of buying a set of injectors there are cheaper suppliers on ebay. The Standard FJ3 it a common replacement. If you are not out for high performance they seem to work fine unmatched out of the box.*
    75 76 77 78 79 80 81 82 83 Datsun 280z Fuel Injectors | eBay
    Its worth buying the o-ring gasket set from MSA and replace them while you are doing the injectors.

    My connectors were all badly worn and damaged. They were aftermarket and the cable was so short I couldn't swap injectors. I had problems with 3 and 4 were partially blocked and I found them using the 9 volt battery and the fuel gauge. I ended up reverse flushing them to get them back up to the other four.

    I got a set of these connectors for mine. This seller was really quick, 5 days to Europe. The quick release makes it easy to do any testing and I made the cable a little longer so I could switch cables on injectors for testing if needed.
    6 Injector Connectors Datsun Nissan 280z 280ZX Z31 300zx EV1 Quick Release | eBay
    Chas
    Last edited by EuroDat; 08-12-2014 at 02:16 AM.
    Chas
    5/77 280Z HLS30 403100 with some modifications
    Original colour: 305 Light Blue. The PO changed it to Red

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    Nova Scotia,Canada,Earth Blue's Avatar
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    The injectors are simply based on a solenoid design. A coil of wire that pulls on a slug of metal when energized. Since the slug is not magnetized/polarized, the polarity of the coil is not important thus the connectors pos/neg are not impt....but Nissan did wire these all the same.
    There is scarcely anything in the world that some man cannot make a little worse, and sell a little more cheaply.
    The person who buys on price alone is this man's lawful prey.


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    Registered User siteunseen's Avatar
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    Standard FJ707Ts are good and not too expensive, $30. They come with the O rings and a clamp.
    https://www.google.com/search?q=stan...w=1280&bih=620
    1972 240Z #918 New Sight Orange
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    Z maiden Jennys280Z's Avatar
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    Siteunseen I was reading through an older thread about you going with the FJ707ts and I wondered how you were getting along these days. Good to hear you're alright.

    Thanks Blue, it was wishful thinking that something was just plugged in wrong.

    Thanks all, I'll look into the more affordable EFI parts for sure.

    Got the injectors swapped but haven't had time to run the motor yet. I'd be out there right now driving it around but I don't want to wake up the neighbors. Damn you, Flowmaster!

    So instead I decided to replace my old battery with a brand new one tonight, until I learned that Autozone has nerfed their Duralast Gold batteries sometime earlier this year. My old equivalent size-24 "DLG" battery has 750 CCA, the new replacement DLG with an "S" added to the part number comes in at only 575. Then he had to switch stickers on the two batteries to make mine look like his, because he already ran the swap through the system before I decided to do it and it was somehow irreversible. So when I go back to Autozone in a few years to replace the battery again it'll look like I swapped it already tonight when I didn't. But at least it'll have that "S" on there so there's no chance of a problem. The last straw was his $2000 battery tester was outputting some crazy numbers on all of the 24's he had left and it was the only tester he had. Leaving with an inferior battery was bad enough already. Leaving with one that wasn't even known to be good was too much to ask for.

    Interesting how a battery with 11.99V or 12.4V between the posts can be in a highly discharged state. I thought the relationship between battery voltage and its state of charge was pretty basic or linear, but I learned there's no accurate way I can tell what the charge percentage is from a volt/multimeter. I wonder if people just wing it, or keep charging their battery till they see 12.xx V, or if the car still starts with the old battery they don't even stress it? I read some articles online last night about discharged batteries and one said that they can cause phenomena like injectors not opening, hmmm. The same article also said that running voltage will be a few volts higher than battery voltage, implying that the battery voltage still provides a baseline voltage even after the car is running? It seems the more I read online and discuss with a sales clerk, the more conflicting info. I get. It would seem that if the alternator is okay and the motor is running, the battery voltage has nothing to do with it, but it seems even more that the battery still does, and so the alternator functioning correctly is more a matter of charging the battery effectively.

    It also appears that I lose between 0.5-1.0V from the battery after installing it in the car, even still testing voltage between the posts. Normal or not, neither the sales guy nor me know for sure. On the bright side, my new tool set included a 10mm deep socket that makes taking the battery on and off a cinch now compared to the knuckles and cussing required with an open end wrench. When I know I'm not going to be driving the car for a while, I'm just going to leave the negative cable disconnected most of the time and see if that "solves" the discharge issue.

    Thanks again for all the help! This site is the best Z clinic on the internet hands down. Yes, we owe it money, I acknowledge that.

  13. #13
    Nova Scotia,Canada,Earth Blue's Avatar
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    cold battery at 12.0V is flat
    cold battery at 12.8V is fully charged

    Voltage from alternator-regulator to charge battery when iding and running is typically 13.5 to 14.5V range

    A hot battery with the car just shut off will show the Vreg voltage then slowly decrease from this to its cold state (over hours). You can watch it drop with a volt meter.
    There is scarcely anything in the world that some man cannot make a little worse, and sell a little more cheaply.
    The person who buys on price alone is this man's lawful prey.


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  14. #14
    Z maiden Jennys280Z's Avatar
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    Feels like 30 horsepower! The moment I touched the gas pedal after backing out of the driveway it was immediately obvious.

    I tapped on the #3 injector about a few hundred times with the plastic end of a screwdriver, and even more uselessly, tapped on the fuel pressure regulator a few dozen times as well. In a really old video from "Big Phil" from HybridZ (turbo280Z on Youtube) he mentioned that a Z mechanic told him he could raise the fuel pressure in the fuel rails temporarily by tapping on the regulator. I'm sure it's a useless idea to make your car faster, but having some extra psi in the fuel rails couldn't hurt when I'm trying to unstick or upvolt an injector. The 2 & 3 wires are still swapped; I suppose I'll swap them back to their proper injectors again. I'll be left having to wonder: Was it physical or electrical or a combination of the two? I question that maybe it was a combination of the two. I brushed the female connectors like a mouth full of cavities in between several soakings with Caigs. Jenn said she cleaned the injectors but they all still looked pretty corroded to me. Looking at the spark plugs again, cylinders 2, 4 and 6 all show lean running conditions so I cleaned #4 and 6 before the test drive. #2 was already cleaned as the test cylinder, and #3 was of course dead which got cleaned first. I've got the battery unplugged for now and I might as well clean #1 and 5 too, which looked like the healthiest of my spark plugs by far.

    Time for the clutch hydraulics. I might be pining for more help in that forum in the next week or so. I'll know more for sure after the clutch work is done whether the transmission has seen its better days. I'm interested in a remanufactured 5-speed from a '77 or '78 280 that has the same ratios as the one I've got now and is plug and play with my stock motor. Thanks again for the pro advice you guys. I wouldn't have been able to do it without you guys. Special thanks to Blue; your wisdom was golden.

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    Z maiden Jennys280Z's Avatar
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    For posterity, I actually did have to tighten up the idle adjuster quite a bit. I had an idle of over 1100 warmed up. I settled it down to about 850 and the screw actually feels 'tight' now.

    The vacuum was already healthy on five cylinders. It must be super healthy now.

    I must have been enjoying the ride too because I caught myself going 65mph in a 35 zone. Actually an oncoming car was flashing his brights at me so I must have looked like I was going really fast. And only then did I check the Speedo. That slowed me down too, since the bro-code for cops is flashing your brights, after all.
    Last edited by Jennys280Z; 08-13-2014 at 08:14 PM.

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    I'm happy for you.
    There is scarcely anything in the world that some man cannot make a little worse, and sell a little more cheaply.
    The person who buys on price alone is this man's lawful prey.


    John Ruskin (1819 - 1900)



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  17. #17
    Registered User madkaw's Avatar
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    So am I reading this correct and between the battery change and tapping the injector fixed the issue?

    You do know that an injector is basically a small selonoid(I always question this spelling). They can stick just like they do on your starter. They can also not want to engage-just like your starter from insufficient batter voltage.It's funny how many cars I have got started with a hammer-
    The voltage your alternator is putting out helps maintain your battery which is the main source for your electronics.

    Like I said-you will really enjoy 6 cylinders
    Steve
    71 240z,bw-5sp 2.4-40 over,balanced,e-88,big valves,ported&polished, stage2,header, triple Mikuni's 40's
    3.90 Subaru STI LSD

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    Z maiden Jennys280Z's Avatar
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    Well I kept the same old battery but I charged it till it hit 12.65V then installed it quickly and started the motor right away. Maybe it wasn't electrical and the injector was physically stuck. It's hard to think that a voltage issue would have affected one injector completely when some of the other connectors looked just as bad or worse. I didn't put any of the metal clips back on and I suppose this is okay? I do want to pull the connectors in about three months and inspect them...maybe when they get this old the corrosion becomes more of an issue faster and have to apply some regular TLC not to have problems.

    The motor felt so strong now that the clutch feels like it's having more issues...vibration or just noise coming from below the center console. When the car was garaged and not running for nine years or so, all the brake cylinders were toast but the clutch cylinders are still hanging in there. I changed the fluid but it turned black almost immediately so there's a lot of corroded rubber probably coming from the master cylinder. The slave cylinder and hose were replaced in '89 but I think the master is the original from '76. So now that the motor's done (never done really, ready to install a new oil sending switch but I'm reluctant that it might be seized in the block) I'll move to the clutch and I'd like to change the transmission fluid too...planning on jacking up the front to drain it, jack up the back to fill it. Lower the back to drain excess fluid out, then jack up the back again to tighten the fill plug. If all this doesn't make the car happy I'll have to start saving for the transmission fund.

    It was actually Blue's comments about the current producing a magnet moving a slug allowing the injector to spray gave me the tapping idea. The alternator is original...still hanging in there. Jennie thinks there's a broken bolt in the front of it, we'll need a pro to do that since we don't have any kits to extract bolts (or experience).

    Happy that the engine runs so smooth now.

  19. #19
    Registered User EuroDat's Avatar
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    Have you changed the transmission fluid since it came out of storage? If its been standing for 9 years it might be a good place to start.
    Clutches don't start vibrating because the engine runs better and has more power. Slipping is a different story though, you will notice that when you engage the clucth and it takes a lot longer to grab when your driving harder or in your case the engines has more power.
    Poor quality oil in the transmission will create more noise and can increase vibrations.

    To change the oil, get the transmission warm and drain it over night. I use a cooper 90degree water pope elbow, a hose to and funnel to fill it from the engine bay.
    Redline MT-90 and Royal Purple Max gear are recommended by many Zed owners, but there are lots of other good brands out there. It should be a GL-4 or a GL-5 suitable for yellow metal (synchros).
    Chas
    Chas
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    Original colour: 305 Light Blue. The PO changed it to Red

  20. #20
    Z maiden Jennys280Z's Avatar
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    Thanks Chas I'll go with one of those two brands. Just read other classiczcar threads on doing this job...looks like all my questions are answered at this point. But the diff oil prob ought to be changed too. Looks like my labor just doubled

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    This car was running last year right? The 9 years is previous. Isn't this somebody else on Jenny's account? Still Jenny's car though. Kind of confusing on what's going on here.

    Anyway, on your noise/vibration from the console area - that's about where the propeller shaft u-joint is, along with the slip-yoke to the transmission. You might check the yoke for play when you're under there, grab it and shake, and the u-joint also. You'll need to pry that one around with a screwdriver to see if it's loose. Look for signs of rust and dryness.

    And when draining the fluid, level puts the drain plug at the bottom I believe. And puts the fill plug at the right spot. No real need to tilt the front or back independently. And the fluid will expand a lot when hot or warm, so don't be surprised if a bunch comes out if you remove the fill plug first. Which is always a good idea, just to be sure that you'll be able to refill it, before you drain the fluid.
    1976 280Z, with some minor modifications

  22. #22
    Z maiden Jennys280Z's Avatar
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    Zed Head, sorry about the confusion. Yep I hijacked her account. At first, I did create a new account name "1976280Z" at first to avoid confusion but never got the verification email. Nothing in spam folder. Then we couldn't remember the username/password until I got back to her place last Sunday and her password was still in the browser cache on her old desktop. She's out of state in grad school atm and gave up on the car before that because she didn't have the time or money to put into it. She was considering selling it for a time but when we couldn't agree on what "fun" car to eventually own, and then the car started to grow on me over time. I think it still has a lot of potential to be a great car but it's not even close yet imo. I used to own a 442 and worked on that myself but the Datsun has been more interesting to work on after all the stories she's had to tell about it. So it's the same car and still hers, I've hijacked the car too in the meantime. She's consulting from afar and referred me here. She mentioned you specifically too Zed Head and a few other ppl I forget and that you guys have saved her hundreds if not thousands in labor cost.

    Your ID on the slip yoke is probably dead on because it does have the "clunk" when accelerating in gear from a standing start especially. J said this was an issue years before the car went into hibernation. A local Z shop specialist at the time acted like he didn't know what making the noise exactly, remarked about the U-joints but she can't remember what he said exactly. Either she couldn't afford the repair, or the guy didn't want to do it or couldn't do it, or ...

  23. #23
    Registered User EuroDat's Avatar
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    That clunk sound "smells" like diff related to me.
    Along with the uni-joints you can also check things like the front diff mount, rear diff cover bolts, rear transmission mount or if could be just play (backlash) in the pinion/crownwheel. These diffs are known to be a little whinny. New oil can quieten in down, but won't do much to reduce backlash. Most of us use extra insulation in the rear to reduce the noise.
    Note: a little of topic but if you are considering replacing suspension bushes in the future, consider the effects of PU (Poly Urethene) as well. Other than reducing flex they also tranfser road and drive train noise a lot more efficiently. Some people regret the move to PU because of this reason.

    The rubber diff and rear transmission mounts can sage over the years, although they look good the metal in the rubber mount can tap each other causing clunk sounds and transfer vibrations to the body. My old ones had dropped about 10mm IIRC compared to the new ones I installed and the old ones didn't look half bad. I think Blue has a how to on AtlanticZ that shows the difference between old and new. http://atlanticz.ca/zclub/techtips/s...end/index.html

    The two bolts on the diff cover (mustache bar) becoming loose over time is another source. Tighten them to FSM spec.
    Chas
    Last edited by EuroDat; 08-18-2014 at 12:08 AM. Reason: Link to AtlanticZ
    Chas
    5/77 280Z HLS30 403100 with some modifications
    Original colour: 305 Light Blue. The PO changed it to Red

  24. #24
    Z maiden Jennys280Z's Avatar
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    Thank you Eurodat we got a new carpet with extra insulation in the hatch for noise reasons last year which doesn't help now that I'm trying to hear noise again, dont think I want to hear it through polyurethane though.

    A 2nd quick test drive and a vacuum test is showing 19 inches. There's a vault of information on here about every problem. I'll get under the car when the weather cools down a bit (95-100 lately). J's really looking forward to driving the car next month.

    Don't want to take the thread off-topic too badly so I will let this dead cylinder thread close with a successful result. You guys are the best thanks again
    Sean

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