Captain Obvious

Unfortunately it's down there somewhere:

I would agree with your assessment. The oil is there only for transients. If you're keeping a steady foot, the oil doesn't do much of anything. Might apply some "anti-oscillation" damping for the loop, but other than that, it's a non-factor. Also, if you can punch it and it doesn't sputter or bog, then that's another data point indicating that your oil is of a suitable weight. As for the problem you're having... Are you sure it's not an ignition issue? Timing slipping around from sloppy gears or bushings or something? How do the plugs look? Can you tell if you've got a mixture issue one way or the other?

I'm no cooling system expert, but I think it's important to have a small amount of flow through the thermostat housing, even when the engine is cold. If that area is completely stagnant, then you run the risk of overheating because the thermostat won't be subjected to the hot water and could instead be sitting in a stagnant cold pool. I believe most thermostats have a small bypass hole built into them to allow for just this kind of issue, but I wouldn't completely block off all those path(s) without first confirming that is the case. Eventually heat will make it's way into that area through conduction and eddy currents, but if you don't ensure some flow somewhere prior to the thermostat getting hot enough to open, it may be too late by the time it does.

Yup, that's the thermostat that's supposed to be on the coolant lines through the manifolds. I'm assuming that most of them have failed or corroded thru over the years and have been discarded and replaced with simple nipples instead. That would be my explanation as for why you don't have one on your car right now. Can't tell from the pic, but is the nipple on the rear carb made out of brass? If so, it's clearly a later mod.

Yes, you are reading those pics correctly. The tensioner piston is no longer in the hole in which it is supposed to live. It somehow became dislodged and is probably swimming with the fishes down in the oil pan. And yes, in addition, since this is an unaccounted for unmetered source of oil flow, it could certainly account for slightly lower oil pressure. Sorry you're going back in again. Just when things started sounding like you had reached the bottom of the curve? You don't get a break, do ya?

Referencing page ET-4 in the 73 FSM... In 73 and 74, there were actually three parallel paths for water to flow through the carb and intake system. All three of them originated from the lower portion of the thermostat housing (the upstream side of the thermostat). From there, they split to three different routes: A) Through the balance tube. Through the intake manifolds. C) Through the carbs themselves. All three of those different routes then rejoined in the plumbing back by the firewall before wrapping around the rear of the engine above the bell housing and then heading back to the inlet side of the water pump. The blue hose appears to be the one that goes through the intake manifolds. Of those three routes, only the route trough the carbs themselves is thermostatically controlled, and that route has been removed completely when you swapped to the round tops. The other two routes are (supposed to be) as free flowing as the small diameter lines will allow. And from what I've seen, they are often so plugged with crud that they might not be passing any fluid at all. I think it's important to have a small amount of flow through the thermostat housing, even when the engine is cold. If that area is completely stagnant, then you run the risk of overheating because the thermostat won't be subjected to the hot water and will instead be sitting in a stagnant cold pool. So a far fetched theory might go like this: If the coolant paths through the balance tube and intake manifolds are plugged with crud... And the path through your flat top carbs was not... And your thermostat does not have a small bypass hole through it... Then you might have caused yourself a problem when you swapped carbs by causing a stagnation in the area below your thermostat that did not exist with your flat tops.

OK, I'm going to try one more time and then I'm really sorry, but I'm going to have to give up. Look at this pic. This is the part you are looking for: See the part with all the arrows pointing to it? That's the FICD that boosts the idle when the A/C is on. That's the part you are trying to find. You suggested that it is part of the EGR system, but you are mistaken. It is not part of the EGR system, it is the FICD and it is part of the air conditioning system. You don't have one on your engine because you don't have air conditioning. I don't know where to get one except used off a car that has A/C.

Despite the independent looking circuits, all six injectors are fired at the same time. Always. However, there are two output transistors in the ECU and they divide the task in two. One of the transistors does 1, 2, and 3 and the other transistor does 4, 5, and 6. The DROPPING resistors do it 4-2, but the ECU does 3-3. But, since the control signals to both transistors are tied together all the injectors are told to open at the same time.

Yeah, I've heard the same as well about one side being NLA. I'm thinking that the guy who owned the left hand thread company had dirt on the suspension design guy at Nissan.

He's been on Craigslist off and on for a little while now as well. 240Z,260Z,280Z projects and parts Datsun "who knew "ugly" was camouflage?" Hahahaha!!!

Both of the inner tie rods have right hand threads and can be assembled onto either end of the rack. And yes, the outer tie rod ends are the same except for the RH vs LH threads. You could use all the same parts on both ends and just make up for it when doing an alignment. Not sure why they went through all the trouble to have the two sides different in the first place. Seems like a lot of extra expense for no "real" benefit.

I used a device called a "blind bearing puller" which is an expanding mandrel on the end of a slide hammer. You put the mandrel though the inner race of the bearing while it's down in the housing, expand it until it's tight, and then use the slide hammer to "knock" it up and out of the housing. Prices for such a tool are all over the map depending on quality. Here's a pic of one such device. This one is a little over $50 on Amazon:

I agree. That resonates with me as well.

You're still mixing thing up... Part number 4 on the drawing has nothing to do with A/C and the part that DOES raise the idle speed for A/C is not in that pic at all Here, maybe this will help?

Good deal. Here's to hoping that we're both gonna be around for a good long time!

Park illegally and use the tow truck to pull the front end up........

You mean the part about being still single and half nuts?

Excellent. Glad you got hooked up with the billet bar. Of course, the design isn't as good as mine, but it's not like I'm actively seeking out opportunities to make more! So what was the contact info that work for the billet source?

Haha! No kidding! Registered over four years ago and today you put up your first post! Welcome aboard!

Nite_Grind, Got your PM. Sorry I was out of town. Did you have any luck getting in touch with that guy on HybridZ at that new phone number? Hopefully he hooked you up, but if not, I sent you a PM back with some info.

Cool video. Looks like your fuel pressure regulator is responding properly to the changes in manifold vacuum. I don't remember the pressure specs off the top of my head... Is 30 psi at idle a suitable value?

Good. If you assumed they were one piece and you didn't pry them apart then they're probably back where they came from and you should be OK. The old ones are probably a little deformed from the pressure over time, but I wouldn't go tearing the whole back end apart again just to change them. Now that you know what you're looking for, you can take a better look at them if you're ever in there again for some other reason.

Not what you're looking for though. That brake warning relay does the opposite of what you want. It's energized when the ignition is "ON" and the engine is NOT running. However, if you were to change the brake warning relay over to a DPDT style, you could get what you want... Use one pole as originally designed for the brake warning lamp and use the other pole to control your power. NC side connected to the switched ignition relay voltage and the common of that pole would be a signal that you could use to do whatever you wanted. Essentially use the NC pole to switch the power from the ignition relay. When the engine starts and the alternator reaches regulation, the relay would de-energize. The brake warning pole would open circuit and your "Hot when the engine is running" pole would close. Just make sure you use a relay that has a similar coil spec as the original one as far as resistance and pull in is concerned and you should be good.

From the description, I unfortunately believe they are supposed to go the same place the upper bearings go in the front. You don't need bearings in the rear, so they use fixed hard plastic spacers instead. If they're about the same diameter and thickness as a front upper bearing then that's what they are. Did you put yours together without any spacers at all between the upper spring perch and the top mount. If so, you're going to have to pull them back apart.

Well I'm not sure I did a good job of explaining why it might not be as simple as you describe above... Any time the key is on "ON" or "START", the "L" terminal of the internally regulated alternator will always have "some" voltage present on it. Even if the alternator isn't spinning. This is because that "L" terminal is connected to the battery through the CHARGE lamp. At the "L" terminal you've got a voltage divider between the resistance of the CHARGE lamp filament and the resistance of the alternator's rotor coil. Accordingly, the "non-spinning" voltage on the "L" terminal is determined by those two resistance values. Any relay coil that you would hang off the "L" terminal to ground would be in parallel with the rotor coil, and I have no idea what the resistance of that rotor coil is. You're going to have to be careful that whatever you connect there has a pull in voltage high enough that it isn't drawn in by that "non-spinning" voltage. In other words, you're going to have to be careful that whatever you connect there has a resistance high enough such that the portion of the current that flows through relay coil isn't enough to energize the relay coil until the alternator has spun up through bootstrap. And in addition, you're going to ask the rotor coil to share it's bootstrap current and I'm not sure it's going to like that. And if that's not enough, that "L" terminal supplies power to the internal voltage regulator and I'm not sure if there would be any unwanted interactions with voltage regulation due to the additional current draw on that control line. The drawings show it as connected just like any other output from the alternator, but I have no idea how robustly it is built and what it's source resistance is. Since it's really NOT just another alternator output, they probably built it smaller and cheaper than the main output circuit and it might not like the current draw of a relay coil. Not saying any of this wouldn't work... Just saying there are lots of things that would need research and testing. :bulb: