kcpope

I used the one from vintage rubber, and I was happy with it. I think it was $150 or so, which is a good compromise compared to $400🫤 I installed with dash in place using the typical rope method. As far as removal, carefully remove the stainless trim pieces, then use any manor of razor blades, putty knives, flat heads, etc to remove the old brittle rubber, being careful to not chip or crack the windshield.

As far as I know, nothing wrong with this approach. I think many folks have had to do this. Kinda a bummer to bend the factory lines, but hey, gotta make it work.

Your brake master cylinder should not have any gasket between it and the booster. There is no fluid or air pressure passing between these two parts, hence no gasket or seal. You likely have a leaky master cylinder. The rubber o-rings inside the master cylinder can leak, causing brake fluid to exit the rear of the master cylinder, then it leaks through the (non-sealed) mating surface between the master cylinder and the booster. It then dribbles down the outside of your booster and causes the paint peeling you're seeing. I'd start with a new master cylinder or get your existing one rebuilt. Keep in mind, you have an early 71, so make sure you verify the reservoirs are in the correct orientation on any new master cylinder you get. There was a change in 1973 (i think) that swapped the front and rear reservoirs. For a 71, I believe your front brake reservoir is in FRONT and the rear brake reservoir is in the REAR. in 1973, the designed changed and those were swapped.

Still fiddling around with it… Does anyone know what this solid black wire is for? Comes out of the factory wire harness at the coil. It’s the only wire not connected to anything for me. Maybe the ground wire for the old points distributor?

Yeah, radio interference, I’ve heard that too. I figured that same interference might be messing with the tach. It’s a long shot, but at this point I figure, why not 😅

That’s within spec for your primary. What’s your secondary ohm reading? also, are you running the little stock condensers? One at the coil. One near the alternator. I’m going to try adding mine back in and see if it makes a difference.

Yeah, I’ve read mixed things regarding the coils. As Zed mentioned earlier, the 280zx dizzy wants to see around 1 ohm resistance, which is exactly what I have. Did the ZX also have a ballast resistor? In general when people convert a 240z from points to electronic ignition, here’s what I’ve read: if you’re using a 1.5 ohm coil, add a 1.5 ohm resistor as well. if you’re using a 3.0 ohm coil, no resistor needed. This seems to be the case if you’re doing a pertronics ignition, but I’m not sure if the same applies to a 280zx dizzy…

Agreed, I’ll do my best to get to the bottom of it. I’d love to not have to swap tachs. We’ll see.

Thanks Steve. If I do the swap, I’ll adapt the 260z tach guts into the 240z housing to maintain mounting points and the correct font as zed mentioned. But before I do any of that, I’ll try pulling the existing tach out and see if I can see any obvious problems. As I’m thinking about it more, I’d be suprised if the e12-80 is failing. The engine seems to run too good for that to be the case. PS: the whole reason I needed the tach was to sort out my vacuum advance timing as I mentioned in my other thread. I went ahead and bought a cheap optical rpm gauge on Amazon that I’ll use in the meantime. At least I can get my timing properly setup, then move on to fixing the tach.

Good info, thx. I’ll read up on other threads regarding everything needed for the tach swap. Yes, my E12-80 module is factory Nissan. I’m intrigued by the GM HEI swap. Could that be a permanent solution if my tach ends up working with it?

Welp, I tried both options I described above. No change. Only thing I haven’t tried is adding the condenser back in the wiring. I’ll give that a shot. Also I didn’t realize that the tach can be pulled without removing the dash. That’s a bit of good news. In the meantime, I’ve found a good deal on a tach from a 260Z. Can anyone confirm if those are voltage driven just like the 280z tachs?

Thanks for the info. Interesting. Before I do that, I’m going to try 2 things: 1. Adding a ballast resistor back in with the existing 1.0/12400 ohm coil, and see if that helps the situation 2. I found another coil laying around in my old man’s garage. 1.3 ohms primary, 10600 ohms secondary. I’ll try this coil with and without the ballast resistor as well. Let me know if anyone prefers option 1 or 2 better.

***edited my above readings because I wasn't reading my multimeter correctly the first time*** Here's the correct coil readings I'm getting: Primary: 1.0 ohms Secondary: 12400 ohms So this coil appears to be within the specs that Zed Head posted.

Good info Zed, thanks. That said, I really want to eliminate all other possible causes before having to pull the dash to get to the tach. Like I said above, I confirmed my wiring at the coil is correct according to the video SteveJ shared. So what's left to test? I decided to check my coil and here's what I got: ***edited because I wasn't reading my multimeter correctly the first time*** Primary: 1.0 ohms Secondary: 12400 ohms Any smoking gun with that info?

@SteveJ @cgsheen1 Ok, I followed what both of you said and watched the video. I tested everything with my multimeter and can confirm that my wiring was correct. My B/W wire with 12V (key on) is connected to the G/W wire. The B/W with no voltage (key on) is connected to coil positive. No changes made. Thoughts on what to check next?