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Hello. New 240 owner here. She arrived today and a quick drive makes me think a tuneup is in order along with carb tuning. I bought bits for the distributor based upon model year, but I think the distributor has been changed. Can anyone help me identify it?

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1983 280ZX Turbo
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I think you'll want to search for documentation on that aftermarket ignition system.

I recall from my 240Z that it needed spark plugs every 10K miles, without fail. New plugs should be one of the first things you do.

Also, your to-do list should include getting the correct hose for that make-do unit.
 

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Discussion Starter #5
Pilgrim, what hose are you referring to? Thanks. I’ve been searching like crazy, just nothing seeming to be the same. I also don’t know why the condenser and extra lead off the water sensor are unplugged?
 

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Test your distributor's vacuum pod by sucking on the connected vacuum hose. If you hear a hiss, the pod is bad (like many are at this point) and just cap the vacuum port that the vacuum pod's hose attached to. That would be a huge vacuum leak solved.
 

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It's not necessary - distributors have mechanical advance it just doesn't react as quickly as engine vacuum. If you can't blow through that hose though, then that means yours is fine and no reason to disconnect it.
 

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Discussion Starter #11
Also, I can’t seem to find where to buy parts to rebuild the distributor. Do you guys have a source? All I can find is new rebuilt distributor or caps and wires or the points parts.
 

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Rebuilt distributors are not available anymore. Cardone (the main one who rebuilt these) ran out of cores to rebuild. If you give your distributor to oreillys or one of those parts stores, they will mail it to Cardone to be rebuilt.
 

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I think you'll want to search for documentation on that aftermarket ignition system.

I recall from my 240Z that it needed spark plugs every 10K miles, without fail. New plugs should be one of the first things you do.

Also, your to-do list should include getting the correct hose for that make-do unit.
I agree, that is an aftermarket optical ignition. Information is here: Crane XR700 You might want to contact them for details on the exact unit that you have as it's age is unknown and there could have been revisions over the years.

That is an optical electronic system that replaces the points. The condenser is disconnected because it is not used with this system and is a holdover from the original points system. The other lead may be from the ballast resistor that connected the points to the coil and may be included in the Crane system and no longer needed either.

Since it seems to be working there isn't anything to do to it other than be sure that it is clean and do the timing. I suspect that the timing is done by loosening the screw at 12 o'clock and moving the pickup sensor as needed for the correct timing. The advantage of optical systems is that there isn't anything to wear out. In simple terms the slotted disk interrupts the light beam in the pickup head (at 10 o'clock in your picture) and when a slot allows light through it acts like the points opening and triggers the spark. Be sure the slots are clean and blow some air through the pickup.
Is there a reason you want to "rebuild" the distributor? With this electronic system the cam lobes are not used so wear is not an issue and if the vacuum advance moves properly there isn't much else to do unless you are hearing bearing noise or some other problem.

Here is a similar picture of my '72 240Z with the original points and rotor. You can see that the water hose has a built-in right angle that is hard to duplicate without the original molded part. If you can't find that you might consider shortening the existing hose which should increase the bend radius. As long as the hose isn't kinked and restricting water flow then it is operationally fine.

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Just in case you aren't sure, the vacuum advance hose is the lowest one in my picture and connects directly to the vacuum diaphram on the side of the computer. If you can apply enough vacuum you can move the pivot plate where the points (optical pickup head on your car) are mounted. If you can't hold a vacuum or pressure then change the hose first - most likely problem and cheapest fix.

Good luck. Enjoy your new ride.
 

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There is a number stamped into the side of your distributor. See the attached chart. It appears to be an early Nissan unit with a conversion kit. The question is was it recurved and should you use other than stock sparkplug gaps because of the pointless (meaning you no longer have to replace points) conversion. The stamped numbers will tell you what you started out with. With just a simple timing light you should be able to confirm mechanical advance with the vacuum line temporarily disconnected. Then you need a hand operated vacuum pump in concert with that same timing light to separately confirm your vacuum advance funtionality. A lot depends on how stock or modified the PO(s) left the engine. As seen on the attachment, a ZX distributor, although superior in most ways can kill a early carbureted higher compression engine. FYI the top line in the chart is the eurospec dizzy, so along with the correct carb needles really wakes these old engines up Stock '72 needles are too lean and will result in engine knock with that curve. Hope this helps
FB_IMG_1554191676970.jpg
 

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I have the documentation for this thing. In my reading, all of these points conversions do not allow for vacuum advance. You'll be fine without it. If the car runs than doing any maitanence to the distrib is not needed. This is the point for removing the points....lol. Like someone said above, change spark plugs, and oil and drive the **** out of it. Now.........you might want to check your timing.......just saying.......
 
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