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TheCrazySwede

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Posts posted by TheCrazySwede

  1. On 5/26/2018 at 10:43 PM, Leon said:

    Ah, you never mentioned it was coming from the pump nozzles! Have you verified the state of the check ball and weight, underneath the inspection screws located beneath the float cover?

     

    Yup, everything sits well. No gunk or corrosion either.

     

    I checked my vacuum via the port that connects to the brake booster and my gauge is hopping all over the place, suggesting a vacuum leak somewhere. Manifold is tight and all the gaskets on the Carbs seem to seat properly.

     

    Since this is a new engine (~1,000miles), could it be needing a valve adjustment after break-in? Perhaps that's what's giving me those wonky readings.

     

  2. Yup, I checked the needles and seats and also made sure they were tight. I tested them one by one with pump running and when seated none of them leaked.

     

    I wanted to try lowering the fuel pressure down to 3psi to see if it made a difference - and it didn't. 

     

    Floats are all set at 29-30mm (spec is 29-31mm)

     

    Yet I am still running rich with fuel dripping from the pump nozzles into the barrels. I also tried smaller size pump nozzles and same thing is happening. 

     

    I do notice that even with pump and motor off, there's still dripping from the nozzle into the barrels for a few minutes afterwards.

  3. Ok, so I tested my needles and all of them seat properly. Ran pump with one unseated top at a time and all the seated ones remained shut and never leaked.

    My fuel pressure is still within spec and hasn't been an issue before...but what can I lower it to? 3psi?

  4. Hello fellow Z'ers,

     

    Recently started having an issue on my Z running really rich and I can  see fuel dripping from the nozzle into the barrels.

    Car ran excellent for months; then suddenly went to start it and noticed my AFR in the 9's and noticed the drip.

    The motor is not stock; has a .495 lift and 290 duration, so keep that in mind.

    Idle Jets it ran - 65, but I also tried swapping in 62.5 and 60's and the AFR stayed the same. 

    Mixture screws are 1.5 turns out. 

    Fuel Pressure is right below 4psi (with 3.5 - 5psi spec) and was tested with two different gauges

    Floats at 30mm (within 29-31mm spec)

    Pump nozzle sizes tried: 40 and 50

    It drips down from multiple barrels, not just one. Can't seem to figure out why this is happening since nothing was changed since it last drove fine.

    Any ideas where to start next? Thanks!

     

     

    Video:

    https://youtu.be/gCfc9WM56DE

  5. Ok, it's been a while since I gave an update, so here it goes!

    Every wire in the car, from front to back, has been redone, replaced or discarded. The car runs on what is needed. No heater, no fan controls, no radio, no antenna switch - not even the fuel light was spared. The car runs on only what's needed, nothing more and nothing less. 

    ijncejTl.jpg

     

    The issue with the idle and pilot jets is resolved, too. Idles and runs on all six cylinders now! I'm not sure what did it, but I replaced my filter, cleaned my tank, cleaned out the carbs as best as I could and messed around with the idle mixture - and eventually it worked!

     

    I've spent many hours now diving into every piece of literature I can find on DCOE carburetors and I've surely learned a lot to the point where I feel very comfortable working on these guys. What I couldn't find much on was what parts of the DCOE family (Weber, Mikuni, OER, Solex, etc.) is interchangeable - specifically talking about jets.

    What I learned is that Weber idle jets work as long as you get the appropriate seats for them. Mikuni Air Correctors work on these carburetors, too, and fit right into the emulsion tube. The mains, however, only seem to fit with OER ones. I went through a lot of different setups to find something that works for this engine and so far the perfect recipe seems to be:

    Mains: 135

    Air: 160

    Idle: 65(OER)/65F9(Weber)

    I am currently running 62.5 pilots, but it's a tad bit too lean when cruising. i've tried 70F8's and 70F9's and they're both too rich. My guess is that 65's should fit in perfectly, but they're still on their way from Japan since I'm going with the OER one. The F9 designation on Webers is the same as the OER.

    ALwwi81l.jpg

     

    I also got a wideband hooked up now so I can get proper readings on this thing. At idle I'm currently sitting at 12.7-13 AFR, it goes up to 14 when cruising under 2kRPM (should richen up a bit with the 65's) and I get in the mid 12's at WOT, which seems to be the sweetspot for this engine.

    UteyEAKl.jpg

  6. If you swap the plug and wire to another cylinder, does the problem move with it? That should at least rule that out.

     

    Any chance it could be the distributor? I'm inexperienced with these things so I might not be of much help here.

     

    I've tried swapping plugs and it's only that cylinder. Haven't tried swapping wires, but the wires are brand new MSD spark plug wires. 

    It could be the dizzy, but I don' think the issue is there once the car is under load above 3500-4k RPM, which is weird. The cap looks good, but I'm gonna try replacing that next.

     

    Hi, Just a thought. If you are getting a spark at the plug and fuel is present, Check that the valve adjustment is correct. If the valves are not closing all the way you will have a miss on that cylinder. If the valve clearances are correct do a compression test in that cylinder to see if you have a bent valve that is not closing all the way.

    David

     

    Compression check comes out healthy and strong. If the valves were an issue, I'd imagine the issue would be more noticeable at higher RPM, but it seems to only be an idle issue. It actually runs much better at higher RPM, which makes me think it's an issue with the idle in the carb since the mains take over right about that mark.

  7. There is an easy way for checking spark. Pull the plug and and attach it to the wire. Start the engine and ground the plug against the valve cover or chassis. If you see a spark between the center electrode and strap than you have spark. Be careful no to get too close to the spark, getting shocked won't be a lot of fun.

    if you are not getting spark check your gap. Also what plugs are you running? Good luck! I have been following this thread for a while. Love the build! 

     

    https://youtu.be/mUOmsGiirTU

     

    I checked that and I get spark. The Cyl5 plug is wet and covered in fuel, whereas the others aren't. 

    Still, unplugging Cyl5 does nothing to the engine and it still idles with 5 cylinders. I'm thinking maybe something is stuck (like the idle jet maybe?) and it springs to life once the mains kick on. Not sure why the plug would be wet, though.

  8. So it looks like it's just Cyl5 now, so it idles on 5cyl.

     

    Removing the spark plug does nothing on this cyl. I replaced all my plugs and issue persists. When I removed plug 5, I noticed that it smelt of fuel and that it was a bit wet around the ring.

     

    Does this mean it gets fuel, but no spark?

  9. It's a hassle, but swapping around the carbs to see if the problem moves with them is useful to see the problem is carb related or not.

     

    If it is, it's going to be a little work to sort out. Lots of trial and error.

     

    One of my Mikunis was misbehaving once, same issue as you - fine on heavy throttle, but not firing at idle. I tried to be methodical in my approach and nothing worked. What did work was stripping the carb to the body, submerging it in water, then blowing air from a compressor through each passage. The thought here being that the water in the passages will grab more detritus while being blown out. In this case I rebuilt the carb afterwards and it worked perfectly. Presumably some dirt was blocking one of the pilot jet passages.

     

    Good luck!

     

    I fear perhaps I might have to go down this route. i also don't have filters on my carbs yet - could dirt and crap have gotten in and clogged some bits up? Thanks for the advice!

     

    I feel like I'm always taking two steps forward and one step back, haha

  10. Take out your mixture screws and see if that orifice is blocked. If you're definitely getting fuel and it runs on all 6 on the mains, then it certainly sounds like something going on with the idle circuits for those cylinders.

     

    I checked those and nothing seems blocked. Even swapped them with ones from running cylinders and got nothing. This is really odd...

    I read online that someone screwed the mixture screws in too tight once and something got stuck so it didn't back out when he started richening them. I highly, highly doubt that's my issue, cause these are brand new carbs and I've been very gentle with pretty much everything.

     

    I'm gonna head back to the spark issue again. I tested spark from the wires straight from the dizzy, but I only visually inspected each plug. I didn't swap plugs (or can't remember if I did) or replace them or anything like that. I got some spare ones laying around. I'll replace those plugs with new ones and try again. Doesn't hurt to try.

  11. You sure you don't have #4 and #5 plug wires mixed up?

     

    Otherwise, I'd check the condition of your idle jets for those cylinders. Could be a clog in the jet or passage. Clean with solvent and compressed air.

     

    Wires are correct. I checked the idle jets and passage - used compressed air just in case. No change. 

  12. Do you have a really quiet exhaust installed?

     

    I don't know if it's just me, but I've never heard an NA L28 that sounds like that. Almost sounds like it's not running right.

     

     

    Kind of sounds like it's running on 5 cylinders - I know the sound well since I foul plugs pretty often.  Could be the recording/youtube though. 

     

    You, gentlemen, are Wizards. 

     

    After reading both your replies over, it grew on me that something wasn't running right.

     

    You guys are on a Sage level of Z Ownership - found out I was running on 4cyl when idling!

    No change in idle if I disconnect Cyl4 and Cyl5. I tested both cylinders for spark and got it - compression test comes out good.

    Adjusting the idle mixture screws, however, don't do anything. These are two different screws on two different carbs. I can hear the engine acting differently if I adjust every other idle mixture, but the ones over Cyl4 and 5 show no difference.

     

    Now underload (perhaps when the main circuits kick in?) the car pulls hard and sounds like it runs on all six.

     

    Anyone have any ideas what's going on? Perhaps mixture screws got something stuck at the bottom?

  13. Do you have a really quiet exhaust installed?

     

    I don't know if it's just me, but I've never heard an NA L28 that sounds like that. Almost sounds like it's not running right.

     

    Not really quiet, but not shouting by any means. It's a custom made Abarth exhaust tailored for my Z. It sounds a bit odd because of the way it was recorded + the way YouTube handles audio. Also helps if you have good speakers hooked up! (A laptop doesn't do it justice.) It sounds much, much deeper in person.

  14. Quick update:

     

    Bought a new harness and I'm going to strip the car down and re-do all the wiring. Figure I'm going to want to do that anyway. Hoping I find something along the way.

     

    Here's the sound of the car with the carbs better tuned (Getting a hang of it!)

     

  15. Man have I spent time fighting the the electric systems.  Good news it's probably solvable! Just takes a lot of time and staring at the schematic! 

     

    So are you saying that you have a short that causes your alternator to fry (outputs >14v) and a causes a fusable link to burn? And this happens when you turn on certain things?

     

    1. Is it the alt/bat fusable link that goes?

     

    2. You are not leaking coolant or something into the alternator? Bad mounts can cause the fan to hit the alternator (have happen to me, twice).

     

    3. If you disconnect the alternator, do you still see the voltage drop if you insert the key or turn on something?

     

    You could try the following:

    1. Remove most of the fuses

    2. turn stuff on/off and check for the drop

    3. If no drop then but in another fuse and goto 2 until you get the drop.

     

    I think you need to isolate the circuts more. There is a ALOT of wiring to all kinds of stuff. 

     

    You could try and remove all the fuses (not the fusable links) but the correct fuses. 

     

    1. Yup

    2. Nope - nothing disturbing alt from what I can see

    3. Haven't tried running without alt yet. Will try this and report back!

     

     

    Ok, if you have an issue when you insert but don't turn the key your ignition switch is likely bad. It's not supposed to do ANYTHING with just a key in it according to everything I can find. If it's internally crosswiring you will get some odd results, which you have.

     

    Also, those other questions are important. Year, model, where the sense wire is going, and where the voltmeter is bridged at.

     

    1977 280z

    The stock motor had 0 issues. These problems appeared the moment I did the engine swap. That's why I thought I might have had an improper ground - but I can't find any.

     

    It's on zcar.com, called "1976 280z wiring problems".  Post #7.

     

    You know what, the other day my "door open, key in ignition" chime was sounding reaaaally funny. I just assumed it had something to do with the 16v+ being pumped out. But yeah, the voltage drop issue does sometimes appear when just inserting my key into the ignition - sometimes not. Usually it appears if I cause the volt drop, the turn off the car and remove the key and NOT WAIT long enough before putting my key back into the ignition. If I wait like 2-3 minutes, it usually doesn't do it, but if I insert the key immediately after having removed it (and doing something that causes the volt drop) the voltage drops again, even with no accessories on. Eventually comes back up again. Really weird. I haven't dug into much behind the dash yet. Maybe that's where my problem lies. 

  16. Try disconnecting your alternator completely. It may have a big short in it.

    If not, disconnect everything wherever you can and measure the battery voltage. Then add things slowly until you get a drain.

    The alternator is new. So far, I've tried the stock alternator, a newer alt with internal voltage regulator (did the bypass trick) and now a new alt with external regulator hooked up to a brand new voltage regulator. All produced same results. I'll try to run it without an alt altogether and see what readings I'll get! Haven't tried that yet!

     

      

    What I'm seeing after a quick look at the schematic for a Z (I'm new to these but work on electronics for a living) is a couple things.

    First, the indication that turning on the lights works but your voltage goes to 0. That indicates that wherever your voltmeter is wired to is seeing ground. I need to know where that tap is.

    Second issue is that voltage spike while running. I'm betting that wherever the sense wire goes is shorted to ground. That would cause it to push the alternator high.

    A few possibilities from looking at the short issue for a few minutes: bad light switch, bad tail lamp (if removing the bulb fixes the issue that's it), bad dimmer.

    I'm going to bet it's two seperate problems.

    I get the same symptoms with pretty much every accessory, except for turn signals. At times of short, turning off the car and removing my key brings voltage back, but simply inserting my key into the ignition (without waiting a bit) results in the drop again, even with everything off.

  17. Voltage "popped up" while the engine is running, right?  You are using a good meter?  Sounds like your voltage regulator Sense wire is not sensing.

     

    You should focus on the "burning up" fusible link.  Fusible links are there for when things aren't right.  So, obviously, something is shorted, probably, on that circuit.  Check the wiring at the starter for starters.  And use your meter to be sure things aren't shorted, before connecting the battery.

     

    Yup, with engine running. Not running shows the standard 12.x. 

    Meter is good and tested. I might actually still be hitting 17v - I didn't linger long enough to get an accurate reading. As I was getting a reading, I noticed that the link was burning up again so I turned the car off. But I did see "16.x" show up on the screen before I put the meter down. 

     

    How should I go about checking it for shorts without the battery connected? 

     

    Thanks for the help!

     

    EDIT: You can see a little smoke coming from where the fusible link is right at the end of the video

     

  18. Having some more wonderful electrical issues :/

     

    To try and attempt diagnosing my electrical issues, I've reverted most of the electrics to stock:

     

    • New Externally regulated alternator
    • New voltage regulator
    • New battery cables (x2)
    • New OEM Fusible links

    With key set to "ON" -

    • Alternator reads 12.20v
    • Fusible Links read 12.20v
    • Battery reads 12.23v

    As soon as I turn on my headlights, the volt gauge in the car drops to 0. Running lights, parking lights and dome light won't come on. Same effect occurs if I try to turn on the fan, use wipers or hazard lights. Headlights come on and turn signals work. One of the brake lights also causes the "short" issue, but with that particular light disconnected the issue no longer occurs. Swapping bulbs with one that does work still causes same issue in that particular light.

     

    Still,

    • Alternator reads 12.20v
    • Fusible Links read 12.20v
    • Battery reads 12.23v

    I checked the ground wire from negative battery - good. I checked my fusebox - good. When I first made the swap, the alternator was pushing out 17v before I swapped it. It may have fried something along the way, but I don't know what. 

     

    Today, however, after getting a brand new battery, voltage popped above 16v again. Dome lights come on. Headlights come on, but I can see my fusible link (Alt/Battery one) is burning up.

     

    Any ideas? Thanks!

  19. Beautiful build and congratulations with a sick set Up! I too have the same taste in nostalgia. I plan on doing the STD set up after im done with my suspension and brake upgrades.

     

    I love the throaty exhaust note. Where dis you purchase the exhaust from?

     

    Thanks bud! Eiji is very knowledgable and really knows his stuff. I bought the exhaust from Abarth Exhausts: http://www.abarth-exhausts.com/datsun/

    If you scroll down, you'll actually find my exhaust as an 'alternative' version of the stock exhaust setup. Owner decided to offer it as a special order since I requested to have a much bigger inlet.

    I bought two of them. One is on the car. The other is on display in the house :)

     

     

    Oh man. That revs quick! That's awesome! Abarth exhaust sounds killer. So how does the motor feel in the car? How is low end?

     

    Motor is amazing! Feels like going from a plastic knife to a Katana. It really is that sharp! Low-End torque is great, but she really prefers to be past the 4k marker. I honestly thought my speedometer was busted for a while there, until I went up against my friend's WS6 Firebird. The real power is up there, but due to how fast it gets there, I'm not complaining! Really is a blast to drive. Currently having lots of electrical issues, though!

     

    156 at the wheels.  :(

    I don't want to hijack a thread here, so I'll be posting all the info and specs in the next few days to see what kind of feedback is out there.

     

    Yeah, that cannot be right. My stock L28 got around 140 to the wheels. As i mentioned above, I went against my friend's WS6 Firebird and my Z flies past it. No way your motor should be making that little. Check your tune!

  20. 1977 280Z with upgraded alternator and voltage regulator jumped.

     

     

    My gauge in the car will read 14.5v and car starts just fine.

     

    If I turn on my running lights, all electronics die out in the car and gauge drops to 0.

    Turn everything off and wait a while - power comes back on.

     

    If I use my turn signals, nothing happens, but if I use my hazards - same thing. All electrics die and voltage reads 0. Same goes for fan.

     

    My headlights work, but nothing else does. Even during the "all electrics dead" period, I am able to crank the engine and start the car.

     

    Using a voltmeter, my battery gets 13.5v with engine running. With all electronics dead, it reads 12.5v at both battery and alternator, even though gauge in car reads 0.

     

    Any ideas why?

     

    Thanks!

  21. So I have been quietly following this for quite some time now.  

     

    Just wanted to say congrats on this being in the car!

     

    So will you be heading to the Dyno after it is running and broken in?

     

    Video and details!  Amazing 

     

    Thanks bud! It's been a long time coming, that's for sure!

     

    For now, I'm just playing around with different tunes on the carbs to see what runs best. The setup that it came with was too lean

     

    A. What the Carbs came with / B. What I'm trying out

     

    40DCOE Weber Carburetors

     

    A. Choke: 28 / Mains: 115 / Air: 170 / Emulsion: F11 / Idle: 45F9

    B. Choke: 34 / Mains: 145 / Air: 175 / Emulsion: F11 / Idle: 55F9

     

    I also got some air horns and those mesh lookin' air filters.

     

    I'll post some videos once I get her up and running well!

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