ByStickel

Thanks for the full reply, David. I have a buddy coming today to buy a 510 from me, and he's bringing a couple of mechanical Z pumps for me to try. I pulled the existing one apart, and the diaphragm looks good, so I dunno. I should check the floats, too. The car ran fine before coming completely apart for resto. I didn't change anything with the carbs, but you never know with SUs.

If anybody was wondering, it looks like L16/18/20 fuel pumps are 2-bolt vs the 3-bolt on the Z. I thought I could grab another pump to install. Nope.

Original-style mechanical pump, so pulling through the filter.

I'm trying to get my early-'71 all dialed in, and had noticed some running issues. It would sputter under load when I tried to move it while cold. It felt boggy when revving, and would backfire on the overrun. I drained and cleaned out the tank. The supply and return lines are clear. I pumped air through the supply, return, and fuel rail. I also used a vacuum pump to draw fuel through the supply line, and it seems to come readily. I bought a new fuel filter, and upon installing it, it filler up to about 4/5 of capacity, but the running issue remained. After re-checking the lines and adding a bit of timing adv. the car started running well, but the filter is now nearly empty. I also ran the car off of a small glass jar (9oz)of fuel, and while running, it drained that bottle in less than 10 seconds at idle, so it seems like the pump is returning fuel to the tank just fine. Right now, while warm, the car revs freely, with no backfires on overrun. I'm not sure what it'll do after it cools off (will check later), but wonder is anyone knows what's up with that filter. I'd feel better if it filled normally.

Yes, the old booster is toast. The rod that holds the disc is rusted in place. Luckily I did have a spare booster that's in good shape. I'm painting and swapping it in now.

Thanks, Patcon! I got some advice from the interwebs, and found the problem. The 'reaction disk' has fallen out of place within the booster. Worse than that, the interior of my booster is rusty from exposure to brake fluid. I'm soaking in to try to get things apart so that I can try to reinstall the disk. Having the disk fall out is a not-uncommon problem, apparently. It happens when the master cylinder is replaced.

There are lots of 5-slots out there, and they're still reasonable affordable. The problem is finding the exact wheel. Many different versions of the 5-slot are out there. My Z came with two from one brand, two from another, and the spare was from a third company: I think you have these This style has more negative offset, and no raised disc at toward the center If you want to find a replacement, write down all the markings on the back side, get the width and backspacing/offset measured, and learn how to spot the minute differences between the brands. I'm sure you'll find one.

I'm in the final stages of the resto of my early-'71, and I noticed a problem I've not seen before. When I start the car, the brake pedal drops. It really drops. If you press on it, there's no additional travel; those brakes are on. Rev it up, and they release. It didn't do this before the restoration; they worked fine back then. Why is the vacuum having so much affect on the booster? What changed?

I usually check Ebay for values. Often, you can find the same item that sold or did not sell at a given price by clicking on the 'completed items' tab on the left. And if that fails, pick a reasonable price, knowing that they'll go to a good home. Keystone isn't a hugely desirable brand, but they're nice looking, and someone will enjoy them.

Thanks Patcon. I ended up putting a bicycle pump on the outlet of the filter and blew back toward the tank. There was a blockage somewhere, probably at the fuel pick-up. Problem solved. Now, onto the OTHER problems (;

I came here to post that I'm having a very similar problem getting my '71 back on the road. Everything worked great when I took the car apart to do the body work. I also get a stream of bubbles coming up into the (new) fuel filter. I tested the pump off the car, and it works fine. I used a vacuum pump to draw fuel through the filter, and no bubbles. The filter level drops as the car runs, until it runs poorly and dies, and will slowly rise back to full when the engine is off. Runs great when it runs. I have about 5 gallons in the tank. I see no leaks that might indicate a place for air to enter. I did read about the possibility of the inlet tube damage in the tank, but don't think that's it. Weird.

Here's one more to add to the history: If these are marks from inspectors, wouldn't we see the same symbols repeating? Some have such style that they seem like marks of pride. That said, some are saying that mine says "dormitory", so who knows? This is in my Z, built in April of 1971 in Yokohama. I was born in April of '71 in Yokohama, which is part of the reason I ended up buying it. We met 46 years later in Massachusetts.

Edit: That fixed it. Took about an hour. Thanks so much for the help!

I guess I don't know if my hazard switch is in good shape inside. The hazards work, and the switch feels good to use. The condition of the wiring and controls in the rest of the car are above average, I'd say; I think the car only has a little over 60K miles on it. Thanks for that link! I'll go there now.

I've had my '71 for a couple of weeks now, and I put a battery in it for the first time in a long time, The car sat for at least 10 years. I wanted to go through and see what worked and what didn't. I did open up and clean out the headlight combo switch. Parking and headlights, dash lights, brake lights, and hazards work. As does the starter, blower motor and horn. That's the good. No wipers, but the relay does click. The windshield washer is also non-op, but I can hear it trying when I press the button. I'm less worried about these items, since I haven't started diagnosing them. The brake lights turn themselves off, individually, when I use the turn signal, but the blinkers do not work. I can detect no power going to the turn signal switch at any time. I'm not even sure which wire/wires are supposed to bring 12V to the signals.Is it the White, via the flasher unit? My wiring harness is also different from the diagrams I've seen. (Lots of threads link people to Xenon for diagrams, but that site seems to be down) Most diagrams have WR and WB going to the left and right lights, respectively. Mine has GR and GB, just like the front of the car. My harness had the GR and GB switched (left and right swapped). This made the outer two segments of each light come on, stacked, rather than having the top elements for running, with the outer lowers for turn signals. I swapped this wires and it fixed that. Still no signals. I also re-did a scary-looking additional ground at the end of the harness, using one of the female bullet connectors (black wire) to ground to the chassis. No change. I do not know what these were supposed to connect to. There are enough connectors to supply the marker light, power antenna, and also these two: P1030944 I removed the original turn flasher unit (with noise-maker?) and tried another. Nothing. I checked continuity between the flasher and hazard switch and on to the fuses. Seems good, but I guess I need to make sure the white wire is good coming back to the combo switch. All fuses are powered when they're supposed to be. Here are the wires and flasher: P1030946 I checked continuity of the turn signal switch and it matches what diagrams say, BUT a couple of the circuits started off at 0 ohms, only for that to rise the longer I held the probes in place. Any ideas what that may be? There are two orphan wires leading toward the switches at the wheel. One is a black wire with make spade, the other a red wire with female spade. The only things i did not reconnect are the two leads from the key buzzer. That's the red wire, but diagrams show a yellow, which I can't find. It looks like that might affect the washer wiper (?!) but anyway... And one final question: there's a relay over on the passenger kick panel. Is that the Accessory Relay? What does it do, aside from click once when I turn the key? And, why can't I find it on the wiring diagram? Thanks!