Dave WM

I have read on the internet (for what that is worth) that Ester oil is compatible with both PAG and Mineral oil (the stuff used with R-12). So maybe a retro fit (that is where you reuse at least one thing like the evap) should use Ester. Another reminder is to change out the hoses for barrier hoses (again a internet piece of info) as supposedly R-12 hoses will allow smaller molecule gases to pass thru. IF I ever switch out for R-134a my plan is to go with all new stuff, including the evap. I have a new evap that uses a standard commonly used expansion valve. Its all alum just like the orig. With that I would go to a PF condenser, hoses and new compressor and of course a generic drier. That being said, The R-12 in my car is still working fine after 5 years since I got the car, the compressor is noisy has been for 5 years and needless to ssy I use it a lot in Florida. The noise has not changed in my ownership. My plan is to leave it be, if it goes then I will do the complete job. As far as flushing the evap, sounds like a good idea if you want to be sure, but the bigger issue is that darn expansion valve. Honestly I would just pop for the new unit, its about 400$ IIRC.

its those crimps i was considering soldering, maybe next time I have a reason to pull the fuse box. They looked very good last time I had it off, I was thinking about it, but I can't remember if the spring clips were fastened to the fuse box (in which case heat from the solder iron may be an issue) of if the removable (perhaps snap in like). Oh and yes it was the 2 from the bottom left side "Dome" light fuse that was for the hazards. The IR gun was not a good idea, as you mentioned the resolution was not good enough to narrow down to the exact fuse. I agree the FLIR would be perfect, a nice diagnostic tool to have. I have a youtube friend that uses one all the time looking for too hot parts on PCB's and point to point chassis.

nice work!

I was starting to cramp up, otherwise I would have pursued the hazards. Getting into those tight spaces is harder the older you get. As an experiment, I am going to try using the IR gun to see if I can pick up the heat off the fuses to see which ones are active. Just a tiny bit easier than popping them one by one. You may note the small O rings on the right hand side, 2nd from the bottom. That is the AC fuse. That one runs hot if you use "MAX" ac. Now the manual calls that "emergency" or something level of cooling. So I guess they realized it was a weak point. My fuse box is in good shape and I have done my best to clean the contacts. the heat is generated at the ends of the fuse connection (the springs). My use of o rings was an attempt to tighten this area up, over the years I am sure it has lost some tension. I have considered trying to replace those spring ends, maybe solder the crimp connections if that is adding heat (the spring ends are crimped to the wires on the bottom of the fuse box), but i have found since adding the o rings the issue is manageable. The problem with the excess heat is it will over time melt the plastic top right over the fuse. since the o rings the melting is not happening, but you do need to check to make sure the O rings are holding up over time.

if there is no video it did not happen..

build date 5/75 turn signal fuse forth up from bottom left side of fuse block. Note this was not the same as the hazard, I presume since the hazards work regardless of ign switch (turn signals need to be ign "ON").

I think its 75% OF the R12 charge in the same system. Not "more". May want to double check this.

sounds fine, maybe the microphone in the camera was making is sound louder, I mean it was REALLY loud before, more than a typical valve tic.

That drier is hard to come by. Somehow a local AC shop got one for me, so you could try there, perhaps they have a wholesaler that can supply. The other option if you have the old one is if you can find a rebuilder, yes they can be cut open and refurbished. I can understand wanting it to be as OE as possible but, in this case I don't think its worth the effort, Just rebend the hard line and go for the cheap 15$ generic drier.

If you really wanted to test it, I would think it would prob have to happen very regularly, Have it opened up like above, have a test stand, and while the engine is running you could try thermal shocking it with some dust off to see if you could find a place on the PCB that reacts. Something to consider would be an ign switch. I have had trouble with mine on start up, I presume trouble could happen while running for the same reason, intermittent connections. It a mechanical device, making is subject to wear from use. As cheap insurance if the problem repeats you may want to replace it. Its cheap (40$ get the nissan OE one) and easy. I carry several spare ECU's and ign modules have tested them all to be sure they work. While on the topic, you should go thru your wire harness and make sure all connections looks good, grounds and pins.

did you find one super loose? that was a lot of noise for a valve setting.

document the fitment of the evap box, ducts ,vents, and controls, It's hard to find that, would be a lot of help for those that want to go VA.

I have said it before I will say it again, the stock 280z setup works pretty good, not great as in its not a meat locker but it does well. In fact I notice that the real issue is trying to cool down the heated interior parts, a few minutes in the sun and you can barely hold you hand to the dash (sunny florida). I will break it down into pros and cons Stock pros: OE can only help with value if you ever want to sell the car, buys like OE. its simple, really really simple, easy to trouble shoot. this is big if you care, it allows for the use of the "VENT" setting, aftermarkets have you block this off. I like the vent on the days when its cool enough to not use the AC and i don't want to have the windows rolled down, besides its just a nice feature imho. It works pretty good, has things like idle up so rpm is kept up under the load of the compressor. The stock compressor is rugged, will last forever. You can get evaps and condensors and tvx if you are willing to spend the money. Stock cons: its old and there are a lot of NLA parts I am talking about control panels magnet valves bottles not the evap/cond which are out there. its based on R-12, I don't know how well the evaporator or stock expansion valve would work with R-134. Some folks "may" find the lever controls confusing, I don't think so but just saying. the stock compressor while rugged is very heavy for the go fast types this is a problem. After market pros: easy to get, just spend money, lots of it, but you don't have to hunt things down. I presume it works well and on does it on R134a, I have no 1st hand exp with these but if the were lousy I am sure it would be known. it does not have to have air bottles and vacuum to operate if that matters. I am sure its well supported by the dealers since its new. it uses modern compressors that prob are lighter for the go fast types. After market cons: its not OE so does not add as much value as a OE for buyers that are looking for all original. a Biggie here, it looks like there is a lot of fabrication, I never see instructions showing pre made parts for the install, its up to the buyer to figure out how to put it in. Do not underestimate this. it deletes (I hate that word) the vent for outside air. this is for cooling and heating as well. Its expensive (that is if you have a complete but non working original ac system that may just need some easy fixing). esp if you have some one install it, i have to imagine the labor cost would be high for a quality job. Now if you have a non functional OE system I would advice trouble shooting it and getting it working. If you have a non AC car but want an OE system your best bet would be to find a donor or try to find a complete system, a bit of a hit or miss here if you are not fully aware of all that is needed. if neither of those appeal to you and your prefer the pros over the cons of an aftermarket setup, I would hope you can find someone that has actually installed one and you can see for yourself the finished product.

thats completely different from the one that came out of mine, besides the two holes, it was a single piece, with not joints, that one seems to have the same joint as the short ones sold in the rebuild kits.

You may find the air pressure to hold the valve closed does not work. You can use some rope stuff in the cylinder as well. If you do try the air pressure, make sure the car is in gear and the Emergency brake is set.

that's odd, i went thru my stash and found my OE bush, it had two ovals holes about 45 degrees apart, EuroDat yours had no holes at all? now I am confused, OP check your original bushing and get back to us. I looked back at your pic, I also could not see the center ring in the middle like my OE one has, but was not sure if it was just hidden by the shadow. I found the pic of my old one from my trans rebuild, the one on the right. the one on the left is the short one, not the omega that I ended up using.

I thought that hole needed to line up with the oil trough.

a large bore rubber hose (like a heater hose) held up to the ear and then move the open end around the engine bay may help zero in on the noise. it sounds external. this technique is very good at finding exhaust leak noise.

for sure not a valve tic. before tearing into bearing issue I would make 100% sure its not a exhaust leak. Does not really sound like one, but with all that exhaust fumes flowing around, you may as well address it just in case. This is getting to be a long thread. Did the car always make this sound? or was there a change then it popped up.

I tried using the existing grid lines as a guide for a thin pinstripe mask, it was prob 2x wider than the existing line. The problem was I was never able to get a consistent line drawn for an even thickness application of the conductive paint. Maybe some kind of foam applicator would work but I doubt it. the problem is getting the paint on thick enough to carry current. No matter what I tried it went south quickly. Patching one small section is one thing, but for me replacing the entire grid with conductive paint just did not work out.

Just saying if you open it you should check anyway, catastrophic failure can occur if tight side wears too much.

I don't see a timing chain guide or tensioner in that list. when you have the cover off check the tight side guide for wear.

from mine, one line goes to the check valve that feeds the vac bottle, the other to the fast idle actuator

you should make sure you have a VERY clean head surface, then use a good quality straight edge, go from one end of the head to the other with feeler gage. you should go diagonal as well. IF you need to get head work I would suggest you ask around, you want some one that has worked on L type heads. there is a lot to take into consideration. I looked into it some, there is not only surfacing the mating surface, but also you have to make sure the cam tower surface is not bowed. If so you end up having cam issues. I have read the correct thing to do is surface both sides and then shim the cam towers to keep the geometry correct and the chain length correct. You may want to contact someone like Datsun Sprit in VA, they seem to have a pretty good rep.