StinkyCheese

Not so good. i took the condenser off and ran an errand. it had the same problem, so i put it back on. I've read about condensers and know why theyre there, but it doesnt seem to make a difference on this car. I only went about three miles from home, but i didnt think i was going to make it home. Coming home wall all up hill. I started out ok, but after about 1/2 mile i lost all power. it felt like i was running on 3 cylinders. i has to climb the hill in first gear and the hazards on because i couldnt go more than 10mph. It really sucked! I tried it with and without the condenser in this state and it seemed the same. I limped home. When i was on level roads i could hold the accelrator at about 1/3 of the way and it would slowly get power and go faster. I parked it, then about 2 hours later I took it around the block and it was fantastic. So strange. I wouldnt think a warmed up motor has any affect on the ignition. In my old '73, does the temperature switch do anything? Btw, arne, i've been reading your homepage and its fascinating stuff, thanks.

The coil is just a generic O'Reilly coil. I had to mod my bracket to get it to fit... Its 1.5 ohms. The condenser on the negative side of the coil didnt seem to make a difference at idle so I didnt even think about that. I will pull it off and try it again this evening. Thanks.

Thats for your help, Arne. Yes, the coil is new. When I had the points on, there was a condenser hooked directly to the negative side of the coil, plus the one on the side of the distributer. I still have the one connected right next to the coil. And yes, the ballast resistor is still connected. I just ran it again for the first time today - went for a drive, didn't have to use the choke at all to get it started, ran about 3 miles to the store. When it got warmed up it started dying around 4000 rpm again. Albiet, this is only when I'm stomping on the gas, which is pretty much how I drive the Z :laugh:.

Update - turns out i had the tach wired wrong, I just played with it like you said, Zforce. So... it runs great (as before) but now I get a tach, too! However... I took it for a nice long ride, running it hard. Lots of power, feels great, and then it started hiccupping at 4000 rpm again! Aaaaaaahhhh! I let it cool all the way down and poked around some more. I took my daughter out for a ride to show her -- it didnt cut out again, until it was up to temperature. Any ideas? (I havent searched the forums yet..)

yeah, I read that sentiment a lot, too. Not buying it!

I was having a problem with my Z cutting out at 4000 rpm so I came to these wonderful forums and did some searching. There are quite a few threads that say, "I just fixed this by installing a Pertronix electronic ignition". There are also quite a few that say, "install a dizzy from a 280z and that fixes it." That seemed like an easy solution, so I bought the Pertronix gear. I installed the Pertronix and it works great, but now my tach doesn't work! So back to the threads I go for more research. This is also a common problem for Pertronix igniters. It just seemed like I was trading one problem for another. :stupid: I kept reading several people saying, "points ignitions worked great for cars for a long time". And a lot of people that don't trust their electronic ignition and keep a spare points system in their car. After all this screwing around, I have to ask - the solution to cutting out at 4000 rpm is to put electronic ignition in. But what's the root cause of the 4000 rpm drop-out? Is it just that I have a 40 year old distributor? And if that's the case, wouldn't it make more sense to buy a rebuilt dizzy?

So, I put the tank back in and all new hoses and it leaked, that was a bummer. But I figured it would, with a 40 year old gasket. I was disappointed with the renu job on my gas tank. When I talked to the guy over the phone, he said that they would disassemble the gas tank by cutting all the way around the seam. Then sand-blast it out, then bake on a coating, inside and out. When I got it back I had the buyer's remorse. They didn't take it apart at the seams, they just cut some convenient holes in it. Which means they probably didn't get all of the surfaces sand-blasted. And they applied the coating pretty sloppily. I had to remove some burrs on the outlet pipes. And the area around the fuel-level-sending-unit wasn't very smooth, either, which may be contributing to the leak. For $345 I thought it would look more professional. Pics attached.

I should have thought of that... duh. Thanks

I did a compression test today on my '73. I didn't know I had to keep the throttle wide open... I got around 150 on all 6 cylinders. I know the manual says you want 170+, but I assume a 40 year old moter losing 20psi is pretty good.. I don't want to repeat the test (it was easy, but I'm lazy, what can I say..). Should I feel good about my 150? I have performance issues (hard to start, hesitates when accelerating from a dead stop, hesitates at around 4000 rpm if I'm stomping on it, back fires, etc, etc). But I don't think 150 compression is to blame, do you?

I put it all back together and I re-used the gasket. It leaks around that gasket. I can't find a sending-unit gasket in any of those websites. Unless this is it: https://www.thezstore.com/page/TZS/PROD/10-2641 ... I don't think 70-74s have fuel pumps, so this is probably it.. Anyone?

When you overhaul the brake system, do you replace the stainless steel lines? Or are those "good forever"?

Mine sounds (and looks) like a small john deere at idle.. Is that bad?

I like the way that looksmin your picture. if i blast it and clearcoat, will it look like chrome? Not reallyinterested in the chrome look.. And I dont suppose i can powder coat it myself, can I?

When I bought mine I towed it on the freeway with the front wheels up. I just put it in neutral and drove away. It was about 60 miles on the freeway. I say go for it. And if it damages your tranny .... Welcome to the joy of the Z. You get to work on it as much as you drive it!

What's the difference between sand blasting and bead blasting? I know its sand intead of glass beads, but how does it affect the finished product? Also, I don't own a sandblaster... Man, that sounds like real work! Won't you be able to see the sanding marks?

Is this written up somewhere?

Yeah, I'm leaning that way, too, unless you commit and do the whole engine bay that way. I've seen some sweet flat-black engines/bays. I'll probably do mine as polished aluminum so it looks right with the rest of the engine.

I noticed my valve cover is leaking, so I'm going to replace the gasket. While I have the cover off, I'd like to polish it or paint it. First of all, if I decide to go "original", how do I get there? I assume there's some chemical you use to treat aluminum (its aluminum, right?), if you have experience with a good one, please educate me. I'm also contemplating going with a flat black and leaving the lettering shiny. Or a powder coat black. If I go that direction, is it just a matter of sandblasting and painting? How do I polish the lettering so its shiny? I searched the site but couldn't find anything. Maybe I suck at searching - has this been written up before? I used to paint cars 20 years ago, but it was always body parts. I searched google, but I'd like to know how a Z person did it...

pics!

sorry everyone, i didn't know oil was a touchy subject!

One thing that I did (don't know if was being dangerous or not..) - I left the key in the "on" position and opened up the dizzy. I loosened the points screw and played with the gap adjuster screw. When I got everything working I could open and close the gap and a spark would go across the points. Once I got that to spark, I put it all back together and it ran..

I got wind of this site today : http://www.bobistheoilguy.com . I kept reading until I realized the guy was insane, but it got me thinking. What is the best motor oil for my 40 year old Z? I've had a couple of high-mileage cars. I'm pretty good about getting oil changes and I've had several cars hit 200k without engine problems/smoking/losing power/etc. But I've always just bought the cheapest motor oil I could find. Maybe I just got lucky? Does oil matter? Maybe my motors last because I change the cheap oil often? When I was in college I had a '72 Z whose engine started "clunking" at idle. I was putting 5W-30 in it and a friend suggested 40W oil. So I put in the 40W and the clunking went away. I haven't even read the manual to see what weight I'm supposed to be using. :stupid: Also, I've always had a overgrown sense of skepticism about motor oil commercials on TV. I'm fond of dismissing their claims as BS. "Use this oil for your high-mileage car". BS. "This oil has special scrubbing bubbles that make the inside of your engine as clean as unicorn tears." BS. "This oil coats your piston sleeves and makes them smoother". BS. Or am I just an idiot? (I've been accused of such before).

Those are all Datsuns?!? I agree, the orange and blue one is pretty cool.

Yeah, I think I'm going to go with this method. I also liked the "storm door spring" idea... I had to travel to Maryland on business this week, so I had my daughter take it to the radiator repair place to get it boiled out. I called the guy and he said, "oh, we don't boil them out anymore, but we can steam it out." I don't know what either technique means! I hear people say, "boil out your tank", but I have no idea what it means. Anyway, I asked him what their services entailed. He said for $170 they would "steam" it out, then put in a sealant. For the exterior, they just steam wash it off. But then he offered another solution. For $325 they would disassemble the tank, sandblast the inside and out, weld it back together, coat it with some kind of paint (?), and then bake it. Lifetime guarantee. I think he called it a "renu" process and they're the only authorized Utah dealer. I probably could have bought a tank for less, but I'm too lazy to look for it. I saw the article on how to do the POR15 - I love the way it looks, but looks like a major pain. I don't want to do this twice, so I'm going to leave it to the pros.. Anyone know where I can get a new gasket for my sender unit? I've decided to re-use the filler hose. It actually looks fairly new. I'm wondering if it has actually been replaced before. Another question - what do you use for clamps? The ones on the car are so rusty and old, I'm not going to re-use them. Should I find the same "two-wire" clamps? Are the regular cheap screw clamps OK? Does it matter?

I'm always amazed with all of the stares and comments I get from people when I drive around. People will stop traffic to roll down their window and say, "nice car, I used to have one." I even went to the pay-and-spray car wash once and this guy watched me wash and dry the car. When I got done he came over and talked about his 3 Zs he had owned. When I left he said, "you made my day." Even when I let my wife or (gasp) son drive it, they come back with stories of people talking to them or waving or gawking. I once went with my daughter on an errand and someone told her, "I love you dad's ferarri"...