Racer X

Most local auto parts stores can have one in a day. If any of the hangars are loose or broken the exhaust will be loose, and when it is loose, it can bump into stuff. Did you do like I suggested and give it a shake?

Did you find any play in it? Is it listed as the replacement? Are the dimensions correct?

Here is a video of how to check universal joints, and what you will see when one is bad (this one is really bad, any play is unacceptable). Your Z has 6 universal joints. Check them all. The front differential mount is two pieces of metal joined with rubber. One of the metal pieces is bolted to the differential, the other to the cross member. If both parts are bolted securely, then it is possible that the rubber has torn away from the metal. To check for this use a prybar too lift the nose of the differential, and observe if this is the case. The transmission mount, and the engine mounts are of similar design, and are checked the same way. Check them. Also, check the exhaust. Grab the muffler outlet and see if it wiggles, observe how much, and if you hear any part of the exhaust hitting anything. A little wiggle is OK, a lot, not so much. Examine all of the mounts, repair or replace any broken parts. Bailing wire or coathangers are not acceptable repair materials.

Not a single picture of the nose mount on the diff showing the condition of the rubber. I would take a look there, use a pry bar and see if there is any play. Those mounts tear somtimes, and that might be the clunking you are hearing. Also check the u joints on the driveshaft and half shafts.

Now think about this for a moment. If the driveshaft was spinning, and the car wasn't moving, then later, in reverse, it moved fine, you just stepped into The Twilight Zone. You really won't know what is causing the noise until you get under the car and have a look.

U joints connect rotating shafts, such as a driveshaft, halfshaft, steering shaft. Tie rods connect the steering rack to the steering knuckle. So, no, not even in the same ballpark.

At some point it becomes an obsession. I have 14 Z cars, 13 S30s covering all three series from 70 to 78, and a 79 280ZX. It started with the race car. Then the brown 72 for Mrs. Racer 1.0. Then someone offered a non running Z for cheap, I offered to haul it off for free if they had a title. Before I know it, the area behind the shop is littered with these things. Mrs. Racer 2.0 is tolerant but secretly wants most of them gone, especially since the values have gone up so much. I’ve decided it is time to thin the herd.

I just had a look at my process and even without the extra spacers the space is tight. I leave the airbox base mounted, and tune for the extra length of the air horns. It gets tight by the strut tower and brake cylinder. The Uni Syn is only about an inch thick so it is easily and quickly moved back and forth. And it is made of metal. Oh yeah.

I just donated because there was too much blood in my alcohol system.

Nice. Probably adhesion failure, for sure. If it was painted in Florida the humidity during the refinishing process would impact that. Still looks like a nice start, and you got a steal at $4k in today's market. Looking forward to seeing your progress.

What is the build date? Interesting that it is at that point where it is assembly time. All downhill. The fun part.

Might be because I have two insulators between the carbs and manifold.

Wow, a pin for every gallon, very nice. They never gave me any pins. Just a couple cookies and some juice. At the donation that put me at a gallon (this was a very long time ago), I announced to the phlebotomist it was my first gallon with that pint. She scoffed at my pride and announced she was well over three, nearly to four. So being the competitive guy I am, it was game on. A couple pints into gallon four they had trouble finding a vein, and after a few tries at stabbing me, I passed out. They don’t like it much when you pass out, and much excitement ensued. I stopped donating for a year or so, and when I went back to start again they had trouble finding a vein, and when they were successful at getting it hooked up, it didn’t want to flow. Didn’t even get a full pint. So I quit going to donate. That was about ten years ago.

I have one of those, never used it. There isn’t enough room between the carbs and strut tower. Someone gave me one of these: It is easy to use and allows enough room to be quick and accurate.

I have donated over 3 gallons of blood over the past 40 years. I only did it for a couple cookies and some orange juice.

Congratulations. I dunno, can you?

Someone said in Washington state there was an offer of a joint for getting vaccinated. Sign me up, dude.

Use the wiring that is already on the car. And yes, that coil should be fine.

I use a tool like this to check for spark.

The bypass valve in the filter is to allow oil to be supplied to the engine in the event that the filter becomes clogged enough that it can no longer pass oil sent to it by the pump. With the multi viscosity oils of today, on cold startup the viscosity of the oil is low enough that the bypass shouldn’t be opening. Clogging of the filter media to the point that the bypass opens happens one of two ways. 1. The car is neglected and maintenance ignored for so long that the lubricating oil becomes so fouled with dirt and carbon (carbon is what makes the oil black over time) that the filter becomes clogged and oil can no longer flow through it in enough volume to keep the engine lubricated. 2. A component fails (bearing, piston skirt, rings and ring lands from detonation, etc.), and the resulting debris gets forced into the filter and it becomes clogged enough to block the flow of oil. In either case, bearing damage will result. And we all know what happens next.

Wait. After all this fiddling about with the distributor and top dead center we jump to the ballast resistor? Diagnostic strategies need to follow a logical set of steps. Doesn't matter if it is a Datsun, Toyota, Ford, Chevy, whatever. The principles are the same. You need fuel, air and spark. If an engine doesn't fire when cranking, start by eliminating the easy to check things first. Like the power supply to the ignition. So. Remove the wires from the ballast resistor. Using a DVOM, check for continuity between the terminals, and from terminals to ground. There should be continuity between the terminals. There should not be continuity from any terminal to ground. If there is no continuity between the terminals, then the resistor wire is open, and the ballast resistor is bad and needs replacing.

We have already answered the question. And you answered it in this post. 2. As we said, each piston travels through two revolutions per cycle. Suck. The piston travels down and draws in the air/fuel mixture. Squeeze. The piston travels upwards, compressing the air/fuel mixture. As it nears the top of the stroke: Bang. The resulting explosion of the air/fuel mixture pushes the piston down, making the crankshaft rotate. Blow. As the piston reaches the bottom of the stroke it again travels up, pushing the spent air/fuel mixture out the exhaust valve. Each of the six pistons do this, just not at the same time. It isn’t magic. It is mechanical engineering. What we need from you (and we have asked already) is when the piston is at the top, which top dead center event are we seeing with a given position of the distributor drive tang. Again, it isn’t magic, and none of us are mind readers. We just need a simple answer. When the distributor drive is in “x” position, what TDC event is happening at that exact moment. Give us the answer, and we will tell you where your engine is, and what you need to do to fix it. I get that you are learning, and your understanding of the fundamentals is limited. We were all there at one time.

No. Each piston reaches top dead center on the compression stroke once for every two revolutions of the crankshaft. Stay focused on the number one cylinder. That is all you need to be concerned with. So do what we are telling you. Get the engine in #1 top dead center, and check if it is on the compression or exhaust stroke. If it is on the compression stroke, stop and see where the distributor drive tang is. If it is on the exhaust stroke, roll the engine ONE MORE TIME to get it to the TDC position. Stop all this needless rotating of the engine over and over and over.

You can see the cam lobes through the oil fill hole.

Suck, squeeze, bang, blow. Four events. Four strokes. Read the stuff at the link. https://en.m.wikipedia.org/wiki/Four-stroke_engine