I just put a remanufactured 280zx dizzy on my 72 240Z. It seems like everything is fine, but I haven't tightened the adjusting bolt yet because I want to get the timing right. When I turned it over, it sounded like a preignition or pop inside engine, and then today when trying again, it just backfired hella loud. I'm thinking its just not timed right? I was going to take #1 plug out and make sure its TDC but didn't have the tool with me. Any ideas?

Make double sure that you have the firing order right. I know that at least one of the Datsun restoration books has a misprint on the firing order. I followed the book and got the result you are describing. The FSM is your friend.

You might also check that the rotter is pointing where is should when you are at TDC. If the PO replaced the oil pump and put the drive gear in 180° out of phase then you will either have to put the plug wires on 180° out of phase to match the rotter or pull the oil pump and re-time the shaft. This also happened to me.:disappoin

It sounds like a bigger job than it actually is. Good luck and let us know how the new dizzy runs!

Ok, I've made SURE that the firing order is right. I hooked up a timing light, and its getting spark, but my battery is dying now so I can't really keep testing at the moment. I turned the engine over for Cyl. 1 to be at TDC, and the distributor seems about at the right spot. I'm thinking that maybe it is a faulty E12-80. If it was defective, would I be getting any spark at all? I had the terminals mixed up in the beginning, and turned it over, would that have fried it? I have an extra module that I could use, but I want to be sure its that. I can hear it igniting sometimes, but its definitly wrong timing.

I'm not familiar with the specifics of the e12-80 but I don't think you would have spark on number 1 with a bad module.

Yeah I kinda figured that. Just making sure. I can't figure this out, is it normally this hard to get the timing right?

it shouldn't be difficult to do this.

I did this same thing on my 73 240. I had to transfer some mounting plates from the points version to the zx version. Did you do that?

One thing you can do is just eyeball it to make sure that the rotor is pointing to the correct cyllinders as it rotates.

Does it matter what year model 280ZX dizzy is used? Reason I ask is that mine just went bad and I don't remember which zx year it came from before. I am going to go with a remanu one from Autozone this time.

Don

Did you swap in the later model distributor base too? If not then the timing will be WAY off if you're trying to ballpark it with the adjusting bolt. The arms for the bolt on each one are at completely different angles.

Here, six pictures down, is a shot of what might be your problem (as blue 72 implies). It is for 77 to ZX but atlanticz suggests that the 240 swap is the same.

http://www.atlanticz.ca/zclub/techtips/distributor/index.html

Edited December 2, 201014 yr by Zed Head

ok, i got the car running finally. I had to move all the plugs on the distributor cap one position ccw, because the other way had the timing way too advanced. But now the distributor is rotated all the way clockwise (fully advanced) and it is still slightly retarded, but only barely. the car runs, but im pretty sure it needs a little more advance. ive read that it need about 8 degrees BTDC at idle, but i cant advance the distributor any more. anyone else had this problem?

If you didn't have timing problems with your stock distributor, your problem has to be what Bill and Bob mentioned in posts 7 and 8.

Yeah i did install the correct mounting base, I bought a complete refurbished kit off of ebay, came with the correct mounting base. I had to stop testing today though because my neighbor couldnt stand the noise. Really lame.

Where is your distributor adjusted to, relative to its range of motion? because mine is all the way clockwise.

ive read that it need about 8 degrees BTDC at idle, but i cant advance the distributor any more. anyone else had this problem?

On the stock distributor there are two advancement adjustments and I assume the ZX dizzy is similar. There is one on the distributor itself, accessed from below the distributor. there is also one that clocks the distributor with the base IRRC.

When I bought my car it was all the way advanced on the side adjustment at 4°. I had to move the second adjustment beneath to get it into spec. You may have a similar issue with the new ZX dizzy.