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Cam Sprocket Position


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4 hours ago, siteunseen said:

No you do not.

Zed Head helps so many people in different threads it gets confusing sometimes. I do it all the time.

Oops.  

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On 3/28/2021 at 7:22 PM, Zed Head said:

Like madkaw says, vacuum leak probably.  You're tuning at idle for the leak, then when you get on the throttle the leak has less impact and your tune is wrong.

I'd try to add your post about the whistling and clicking at the intake manifold but multi-post quotes on this site are difficult.

Your symptoms still sound like the "lean problem",  just for carbs.  Don't know if it's your throttle blade shafts or intake manifold gaskets but it seems to fit.  The SU's might be even more susceptible to vacuum leaks because of the way they use vacuum to raise the pistons.

Anyway, everything else looks pretty good.  Don't know if your oil pump shaft is off or not but you said that ignition timing was correct. 

 

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14 minutes ago, Zed Head said:

I'd try to add your post about the whistling and clicking at the intake manifold but multi-post quotes on this site are difficult.

Your symptoms still sound like the "lean problem",  just for carbs.  Don't know if it's your throttle blade shafts or intake manifold gaskets but it seems to fit.  The SU's might be even more susceptible to vacuum leaks because of the way they use vacuum to raise the pistons.

Anyway, everything else looks pretty good.  Don't know if your oil pump shaft is off or not but you said that ignition timing was correct. 

 

Not enough history here . Did this motor ever run right ? Did this happen only after the carb work ? 

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It would be nice to swap out with a known good dizzy . Maybe the shop fried your ignition when they installed it . Did it run okay after they put the Pertroni  in?

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Posted (edited)

@Zed Head /All:  Here's my complete history with this car so far...

First of all, about me:  I’m no “expert” mechanic, but I’ve done many repairs over the years, including replacing a tranny & a cylinder head, starters, suspensions, etc. – simple stuff mostly though.   

I bought my Z car about 2.5 years ago.  The previous owner told me that he & his mechanic “could never get the carburetors adjusted right”. (Hmmm).  It had been under a tarp and not driven for at least 10 years prior to my purchase.  

Most of my time with the car has been spent doing body work (in all the usual places).

Last summer, after changing all the fluids and filters, I started her up and had a couple weekends with the car running awesome. It was great!  Initially, there was some crap in the fuel lines, but that cleared up after a couple  fuel filters.  I put 50-100 miles on it, but then it started to run poorly (ran rough, low power - thought it was running out of gas.)   It turned out that one of the chokes was stuck down, so I cleaned it and it ran great for another 50 or so miles.  Then I had similar problems with the other choke which I fixed as well. 

Soon after that though, I had it running smoothly in my driveway, and as I was looking looking down at the exhaust, it suddenly just stopped running.  Dead.  Turned over, but wouldn’t start.  I checked the chokes – they looked fine. 

So, just to get it started, I put in new points, plugs, condenser & coil.  Wouldn’t start 

So I rebuilt the carbs – very carefully - using the Z therapy videos and LOTS of coaching from Steve Epperly at Z Therapy.  I’m 99% confident that they’re rebuilt & set up correctly.  I’m on the list for rebuilt carbs, but Steve’s skeptical that carbs are the issue.  (HUGE shout out to Steve by the way!)

Last year around Christmas time, it was getting too cold to work on it, so I brought it into the local shop.  They were trying to diagnose it, when I got a Pertronix system for Christmas.  They suggested they install it to see what would happen.  They installed it, and got it to start, but it’s had the symptoms described above ever since...  

A couple of other potentially interesting details:

1)     When I changed the points, the distributor was pretty dirty, so I pulled it to clean it and bench-install the points.  The distributor slipped into a shallow tub of EvapoRust and was partially submerged overnight.  I blew it out with air, and it seem to spin ok, so I forgot about it.   I haven't taken it apart yet...

2)     At one point I replaced the ignition switch with an old, used one that came with the car.  I can’t remember exactly why I did that, but as I recall, I was not getting enough voltage to the coil, so I tried it.  (This was around the time of,  but prior to, replacing the ignition parts.)  It ran fine for a while after I swapped out the ignition switch,  but I’ve wondered if this might be part of the problem…

3)     Based on many conversations with Steve Epperly, he recommends swapping the distributor with one with points as a test, which I’m currently trying to source.  

So, that’s my story.  Other than swapping the distributor and rechecking the manifold gaskets, any thoughts?  I WILL figure this out,  but I want to do it while I'm young enough to drive it!   I’ll take all the help I can get…Thanks Y'all!

Edited by Jughead
clarification
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I'll throw a wild guess out - check your grounds.  Distributor to block, block to battery, etc.  Might be that when people are messing around with the distributor that they disturb  a bad ground and it gets better for a short while just from the movement.  Good spark is all about a good circuit, good current flow, through the coil, and that goes through the ignition module or points.  Since it ran well once, and the good stuff happens after somebody messes with the distributor, and others have focused on it, that seems possible.  That's why Nissan adds a separate dedicated ground wire to the distributor body, even though it's already bolted to the block (actually the timing cover).  Grounds are the secret cause of many problems.

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BTW:  Is the that little (~ 3" braided) wire the only thing that grounds the points?  Where (on the distributor) would you attached a secondary ground?  Thanks!

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I grounded mine to the screw that holds the condenser, over to a coil mount bolt. Then a bigger wire from the coil mount bolt to the battery directly. 

IMG_3781.jpg

 

The points ground from the advance plate to the body through the internal wire.

IMG_3782.jpg

 

Also look for cracks in the plastic isolation pieces as they can short out too. 

IMG_3780.jpg

 

 

 

Edited by Terrapin Z
damn autocorrect.
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First thing to do might be to just measure resistance from the mounting point of the Pertronix module back to the battery negative.  Ignition modules usually ground through their mounting points and since the Pertronix is a points replacement it would also.

Then keep your meter connected and wiggle wires and move things around and see if the number stays low.  I think less than about 1/2 ohm is a good number, over that distance.

Check all the points TerrapinZ showed for sturdiness.  Check your positive connections for problems also.

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Gents,  I'll check all those  connections out this weekend.  (I won't be able to test this weekend though, because I'm waiting for a cam oil tube from Yoes Racing. 

In the meantime,  here's a distributor I bought on ebay (see pics) .  It came from  Kuwait(!).  My plan is to swap it with the old distributor as-is - with the points, so I have some more questions:

1: What do I need to do under the hood in order to revert back to points from a Pertronix set up, other than a) Reconnecting the Ballast resister and b) Reinstalling the condensor on the coil bracket?

Question 2: Should I leave the 3.0 ohm flame thrower in or re-install a 1.0 ohm flame thrower that I have? (I'm guessing the latter.)  

Question 3: Is there good wiring diagram anywhere that would help in this process?  (I have a Haynes and the FSM.)

Question 4:  What am I NOT asking that will get me in trouble?! 🙂

Gracias, Amigos.

Dizzy 1.jpg

Dizzy 2.jpg

Dizzy 3.jpg

Dizzy 4.jpg

Dizzy 5.jpg

Dizzy 6.jpg

Dizzy 7.jpg

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I'm no expert on distributors, but I think that is a euro distributor and may have a different advance curve. 

I found this old post about that very dizzy. I also found this chart showing the advance differences. Maybe someone here can explain what the different curves will ultimate mean for your set up. 

Just to add to your frustration 🥴 I hope it works for you. 

 

 

Screen Shot 2021-04-06 at 6.51.35 PM.png

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Oops! Looks like a d608-56a, hard to see but there is a d609-56a in here. Sorry guys, carry on while I wake up.

I have know idea what this thread's about but I do have that Excel spread sheet @Walter Moore put together and it has the d611-54. 

image.png

Edited by siteunseen
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Posted (edited)

Here's a better picture of showing the model number.  Also below is a picture form my Haynes manual where it's referenced.  Good to go? 

My only concern is that it's for a car "with emission control systems" and I've removed most of my emission control components (air pump, non-return valve & flame trap).   I'll triple-check for air leaks (again) around these components, but other than that, any issues with running this distributor?

 

Dizzy 8.jpg'll

Dizzy 9.jpg

Edited by Jughead
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15 hours ago, Jughead said:

1: What do I need to do under the hood in order to revert back to points from a Pertronix set up, other than a) Reconnecting the Ballast resister and b) Reinstalling the condensor on the coil bracket?

Question 2: Should I leave the 3.0 ohm flame thrower in or re-install a 1.0 ohm flame thrower that I have? (I'm guessing the latter.) 

It should just drop right in to the same spot the old one comes out of.  The Pertronix conversion is all under the distributor cap.  The one ohm coil would be a match for the ballast resistor.  Like madkaw says it should tell you if the distributor is the problem.  Set the points gap and it should work just fine.

I don't think that you need to worry about the other condenser.  That's the radio noise condenser, not the points condenser, which is already installed on your new unit.

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  • 2 weeks later...

Hi all.  Since my last post, I have done the following:

1)      Installed a replacement cam “oil sprayer tube” that I got from Yoes Racing heads (See picture below)

2)      Installed the new old stock (NOS) distributor shown in my previous posting. 

3)      Set the points gap.  Reconnected the ballast resistor and put the 1.0 Ohm coil back in.

4)      Started the engine & adjusted the timing.

Result: It started quickly and ran about the same as described above,  BUT

As we were adjusting the carb mixture, the engine started to sporadically shake, with a corresponding metal-on-metal “clunking” sound - similar to the sound a carb piston makes when lifted and dropped in the carb body without the damper rod in.

We shut the engine down to check under the valve cover and make sure cam oil bar was OK, which it was. 

Then, using a remote starter switch we turned the engine over in short “bumps” to watch the valves and cam operate, and to locate the “clunking” sound.  We found the “clunking” sound to be coming from the timing chain slapping against the timing chain guides/timing cover as the engine rotation come to a stop.  Depending on where the rotation ends up after bumping the starter, the chain can be very tight, or pretty loose. 

Is this right?  Or should the chain tension be constant - no matter the position of the cam/crank? 

The clunking sound is pretty noticeable, but it might’ve been there the whole time and I just never noticed it. Don't know, but now I'm wondering if this is what was causing the tuning issues described above...    Thoughts?

New Cam Oil Distributon Tube.jpg

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