jhm

The same blower is used for heat, fresh air, defrost and AC (even on dealer-installed AC systems). You may possibly have two flaps inoperative, if you are getting neither heat in the footwells nor defrost on the windshield. I would also check the ducts feeding the defroster. They can often pop off their inlets/outlets, or just disintegrate altogether....they're made of some kind of cloth material.

If the HVAC system has been replaced and/or modified by a previous owner, there's really no way to answer your question. The stock system is very simple and straightforward. A valve controls the amount of hot water coming through the heat exchanger and mechanical cables operate the flaps to direct the air into the cabin. If you're not getting airflow from the lower vents in the footwells or the defroster vents, either the flap's not directing the air where you want it or the ducts are not transporting the air where you want it. When you switch ventilation modes (e.g. from vent to heat to defroster), can you hear the flap system moving? It usually makes a very obvious sound when it's being manipulated. The AC modifications may have rigged the system to only blow air through the central vents; but the only way to know for sure is to dig into it. They could have disabled components of the system by removing control cables, removing certain ducts, blocking off certain parts of the ducting system, etc. That would be my guess from your description of the issue. BTW, from your picture....that is the stock blower, so it does not appear that the AC modifications replaced the OEM blower with an aftermarket blower.

Yeah, it certainly does look like a seat belt warning relay; but those were only intended for models with A/T (as tamo3 was alluding to). Are there any numbers/letters stamped on it?

Your diff may have been swapped by POs....just get under there and see what you've got, to know for sure. If you can't tell by inspection, take some pics and post them. We'll be able to tell you.

Just curious, Jon...is this the first time you've had this issue? Did the course favor right turns vs left turns? Hope the new valley cover and PCV do the trick for you.

Some good ideas for chassis stiffening/bracing here: https://imgur.com/a/R27sh Most of these are from HybridZ members.

Yes, good clean connections on all your electrical connectors is essential....usually the first step one would take when troubleshooting an issue. Glad you got it sorted.

Not entirely sure what you're asking; but if you're looking for full schematics of the factory wiring, you can download free FSMs from here: http://www.xenonzcar.com/. You will likely be removing the fusible links from the system, and hopefully replacing them with technology from the 21st century. You can retain the original fuseblock, if you want, but I'd recommend inserting relays into the electrical system for running lights, headlights, starter, and any other high-load componentry you may have. Replacing the 45-year old wiring with new heavy gauge stuff will ensure full power to all your components. Ensuring that you have good grounds everywhere is essential....they get corroded and ineffective after a few decades. I don't know if this is what you were looking for, but good luck with it.

Did you happen to read the electrical chapter of the FSM, that I included in my earlier post? There's a section devoted to troubleshooting problems with all the gauges, including the temp gauge (page BE-46). The test you asked about would only work if all the wiring between the sender and the gauge is intact and functional. The most thorough way to troubleshoot an electrical circuit is to start at one end and systematically analyze each component of that circuit from end to end. The temp gauge circuit is defined on page BE-34. You may find that there are multiple issues within the circuit, but you'd never discover that if you were taking a haphazard approach. Not trying to be a dick here....really. But I'd recommend taking a more logical, systematic approach to troubleshooting problems; otherwise you're going to waste a lot of time and money. My two cents FWIW...

Unless a previous owner boogered it up, the wire should connect/disconnect via a clip-on electrical connector.....should be a bullet connector, but I guess it could be a blade connector. If it's not, do it right and crimp on the correct connector for the new sending unit. Hopefully the new parts will fix your issue.

Yes, it feeds directly into a coolant passage and will leak coolant when you remove it. As long as the engine is not running, the coolant will not be under pressure; so it's easy to plug temporarily while you're replacing the sender. You said "attach the yellow hose". I think you meant to say yellow wire?

May be able to help. Let me check my stash and get back to you.

If you only have a Chilton's manual for reference, that's part of the problem right there. Aftermarket service manuals are often questionable....sometimes they're useful, sometimes not. If you don't have the Factory Service Manual, you can download it for free at: http://www.xenonzcar.com/s30/fsm.html. I've attached the Body Electrical chapter here to get you started; gauges start on page 31. Body Electrical.pdf

Yes, R180. If you're wanting to know the gear ratio, the only sure way is to pull the back cover -- the ratio is stamped into the ring gear.

This may not help with your immediate problem.....but once you get things working, you can physically test the accuracy of the temp sensing system with an IR gun....see if you're getting the same readings on your gauge as you get on the gun. If you determine that your sending unit is out of spec, a new one can be purchased here: http://www.thezstore.com/page/TZS/PROD/16-7110

No offense....but yes, trying to run the engine with a wrench on the driveshaft is pretty dumb. If the nuts are frozen/rusted on, heat and penetrating oil are typically best way to free them up. It may take a couple days for the oil to soak in and free them up. Other than that, cutting or grinding them may be your only option. If you decide you need a new driveshaft, I have one from a 1973 4-speed in really nice shape for sale. Good luck with it.

Ah, now I understand. Is the motor/trans already pulled from the car, or are you trying to swap the transmission from below (i.e. leaving the engine in the car during the transmission swap)? Obviously could be tricky reaching some of the bolts if the latter. My personal preference is to always pull the engine; but if you have access to a lift and a good transmission jack, you may prefer trying it without pulling the engine. Do you have the FSM? If not, you can download free manuals for every year at: http://www.xenonzcar.com/

Why would you think there's a different process for separating tranny from a siezed motor vs a non-siezed motor?

Glad everything worked out for you; thx for the update. I have never had anything but good experiences with Bad Dog.

A link will not work, unless the user is a FB user and a member of the specific FB group. I posted your discussion thread here on his FB post, so don't be surprised if he gets in touch with you.

FYI -- there's a guy who just posted on the FB page "V8 s30 Owners Group" about a group buy for RKRs. Here's your chance to get those custom sizes you're wanting.

Yes, weight adds up very quickly. The later bumpers (and mounts) were close to 100 pounds vs the 240's sheet metal bumpers.

Joost, as I mentioned previously, it sounds like the starter solenoid is failing. The problems with the lights are separate issues, and will need to be diagnosed separately. A systematic analysis of each circuit end-to-end is the surest, most thorough approach to trouble-shooting electrical problems. The FSM is invaluable throughout this process.

No, the ignition relay and the starter solenoid are two separate units. The ignition relay is on the relay panel in the passenger footwell. It's discussed in the first chapter of the Body Electrical section of the FSM. The starter solenoid is the small cylinder adjacent to the starter motor -- it performs a similar function as a relay, in that it responds to a small signal and passes on a large current to the starter motor. If you hear a clicking noise from the engine compartment when you turn the key to "Start" but the starter does not engage, that can be a symptom of a bad solenoid.

Do you know if they're back up and running? Last time I checked (which was a while ago), they were a long way from 100%. The times I have bought parts from them, they always had outstanding customer support.