Carl Beck

Hi richard1: First Answer: R12 or R134-A really considered by themselves do not matter. Both have to be considered in the overall context of the specific system involved. Compressing a gas at one point, letting it expand and absorb heat at another point, then dissipating that heat at still another.... involves several different components in different ways. Because the molecular size of R12 is larger than that of R-134a each gas requires different design components to be used in the A/C System. For the sake of efficiency, in picking up and dissipating heat... the gas molecules have to be keep in close contact with the metal tubes in the evaporator and condenser. While the difference in molecular size of the two may seem very small...compressed and moving at high speed though the system, the very small differences compound to produce very large differences in results. So systems designed to run 134a have smaller diameter tubes and more of them, than systems designed to use R12. You can run 134a in an R12 system, but you will lose about 20% of the efficiency of the system - -- You can make some of that loss back up, by running higher pressures, moving the gas faster and conducting more air flow over the condenser and evaporator... but at the same time, you'll most likely be trading off system reliability and longevity. Plus having to install larger and/or more powerful fans etc. The rubber A/C hoses that used to contain the R12 molecules, will not do as good a job of containing the 134a.. it will slowly seep out, and in so doing, it will slowly degrade the old hoses as well. Systems designed for 134a have higher quality shielded A/C hoses. Likewise the compression fittings in the old R12 system, that were tight/secure enough to contain the R12, will not do as good a job of containing the 134a. Systems designed to use 134a have O-ringed compression fittings for that reason. Modern A/C systems, that were designed specifically to use 134a are just as effective/efficient as the older R12 systems. If you plan to keep an old R12 system - and you have rebuilt it with new R12 components to avoid leaks... I'd keep it filled with R12. Yes it is more expensive, but then it doesn't take much to charge a system in the first place, and the old R12 systems held their charge for years and years without a problem. On the other hand, if you are going to install a new system - make sure it was specifically designed for 134a. Aftermarket manufactures, and indeed A/C supply places will tell you either gas can be used in their systems. So many years after the change over to 134a, most of the newer system components have indeed been redesigned for 134a... but you still have to be careful when you buy... and yes quality components are more expensive in the 134a systems. The newer compressors (rotary type/style) can be used with either gas, as they all have o-ringed fittings in the first place, and the compressors are fully sealed to contain the necessary pressures. FWIW, Carl B.

Hi Jim: What can I say?..... I understand your perspective as an event organizer/worker. I simply have a different perspective to express. Respectfully, I believe that you have the focus of your attention and/or concerns placed on the wrong group of people, if the Annual ZCCA Convention is ever to become the event that it would be capable of growing into. I guess it would depend on what the actual "Goal" is. a) to hold a reasonable event year after year at the Annual ZCCA Conventions around the country; or to actually grow the ZCCA's Annual Convention Car Show into the Leading National Level Event for Z Cars that it could become. The number of Z's entered in the annual Car Shows at the conventions "seems" to be stagnating at around 200 cars. Some years more some years less... but over the past 16 years the attendance and entries have not grown consistently larger year after year. That indicates that too many people are not returning year after year, while being joined by ever more new attendees from the local area, or new owners coming into the hobby. By focusing on what is convenient, fun, easy, practical or desired for the people "hosting" the event - - you have lost track of the real "customers". The real customers are the individuals that put tens of thousands of dollars, plus untold hours into their cars, then at great personal effort and expense bring their pride and joy to the convention, and pay to enter a Judged Car Show. You are absolutely correct - given copies of their judging sheets the same day - would allow all the participates time to talk to one another, look at other examples that did not contain the flaws they were dinged with, and yes... so what... they would know ahead of the closing who won at least in the their class - - but they would still have to be at the closing to get the complete story, and receive the honors they are due. It would also give them time to talk to the Judges about how to correct the items they lost points for, or to protest and resolve differences of opinion while everyone is still gathered etc. etc. Here in Florida, for our Government at all levels, we have the "Florida Government In The Sunshine Laws". There is a reason for that and it should not be lost on the ZCCA .... The Judges and Event Organizers, going off in closed sessions, totally up the scores and announcing the results days later, at the very end of the convention, denies the participants any real recourse... Once off by themselves at home, they have no opportunity to talk to one another and compare cars and notes etc. IHMO all of that severely hurts the creditability and objectively of the entire process. If the judging sheets were mailed out a week later, a month later or six months later - it really wouldn't matter that much. The participants would still be home by then... with no one else to talk to, or work with, in their efforts to improve their vehicles for the next years event. Perhaps that is one reason many do not return the following year. I only speak for myself as a spectator .... but I would have liked to have seen the Scoring Sheets posted publicly while the cars were still available to for viewing. That way I could clearly see what area's to focus my attention on while restoring a Classic Datsun 240-Z of my own. Not to mention having the time to talk to the owners of the prize winning examples about how they did it.... No system is perfect and I don't mean to be too critical (although it may seem that way)... just some honest feedback from the peanut gallery. FWIW, Carl B.

BenJammin: You got a much better deal - - - a really "rust free" body alone is worth at least $2,500.00. $500.00 is a steal.. FWIW, Carl B.

If that is the actual case - they have a totally screwed up process and they need to fix it. Every car had a scoring sheet - and it should have been simply photocopied and handed to the participants when it was completed by the Judges. The participants should have had their copy at the same time the committee gathering and totalling the scores got their's. FWIW, Carl B.

What you have to watch is the length of the shaft, on the lug nuts for mags. Measure your old one's and replace them with the exact same length if possible. Sometimes it is no longer possible because the industry is now making only two or three standard lengths. In that case you have to get as close as possible, then use extra thick washers or two thin one's - if the lug shaft is too long. Just make sure the lug shaft with the washer installed - does not stick through the thickness of the wheel. FWIW, Carl B.

Not normal for the brackets to not be in line with each other.. so your first picture shows the problem, with the seat bottom on the right. Take that left hand bracket off and look under the vinyl... to see what is going on.. Carl B.

Hi Ron: The first few months of production for the US Spec. 72 240-Z, they were still using the webbing under the seats, and there was no seat belt warning light. There did not have the self retracting seat belts then either. Matter of fact, the first month or so, the body did not have the "pocket" in the floorboards for the self retracting mechanism. They all did have the fully reclining/flip forward seats however. So the change over to the seats with springs, the addition of the seat belt warning lights, the self retracting seat belts - came later. Along with the horizontal rear window defroster lines replacing the verticals in Jan. 72 So 62xxx might be a good number for the change in the seats, as they had to be changed for the seat belt warning system.... I just wondered if the TS was related to the seats or the switches, as you didn't publish the TS info. at first.... No progress on the seats yet - that is one of those situations that you wish you could get your hand on them and figure it out yourself... ;-) regards, Carl B.

That depends upon where you live, and what the Emission Testing your 82 might be subjected to. If you are sure that your Z won't have to pass an Emissions Inspection/Test... you might get away without it.... But make sure you know what the law requires in your State before you do anything. FWIW, Carl B.

Oil pressure in any engine is "relative" to that needed to flood the main bearing surfaces with lubricating oil, and also maintain the necessary clearances between the bearing surfaces and the connecting rods or crankshaft. Oil pressure in an L28 should be 12 to 15 psi per 1000 RPM up to 3000 RPM as I recall. The oil pump has a pressure relief valve that limits oil pressure from the pump to around 45 to 55 psi. So your oil pressure would be "low" if it were in the 25 to 35 psi range at 3000 RPM and it would be "high" if it was in the 55 to 65 psi range at 3000 RPM. It is not uncommon to see oil pressure readings drop to 5psi at idle. Changing to fresh oil and new filter will usually increase the oil pressure readings on your gauge by 10 psi.... old diluted and/or cruddy oil will thin out and lower your oil pressure... As previously mentioned - the sending units and gauges in our Z's are not the most accurate available. So if you have fresh oil and filter, with the proper oil level... and your gauge reads low.. I would first suspect and replace the sending unit , as well as checking the wiring connections. FWIW, Carl B.

No... your Right Hand Bracket, with the adjustment lever - is where it is supposed to be. (at least that is where it is on all my cars). The problem is with the Left Hand Bracket, it seems to be bolted in to the side of the seat back - too far forward, and the top of the bracket is at too steep an upright angle. I wonder if some previous owner, stripped the original captive nuts in the seat back - then just drilled new holes farther forward. Keep trying... good luck, Carl B.

Hi Dave / everyone: Great article and greatly appreciated I'm sure. Nonetheless, I have some questions in my mind... call it curiosity really. First: I do not remember the wipers being any problem at all when the 240-Z's were new. Yes they could have had a faster speed.... but they would run on a dry windshield no problem. On most of the Z's I've worked on - with 30+ years of age and wear - it's not the motor that is slowing down, it is the linkage pivot points that become corroded, the grease that drys out and hardens etc. In which case, you have to take the linkage apart, de-corrode the stub axles/hubs (so to speak), re-lubricate them. In some cases the corrosion has destroyed the metal, and they have to be replaced. I suppose the gear drive mechanism itself suffers from the same causes. By making the Honda Motor swap - - - are you simply using brute force to overcome the real problem of sticky/corroded pivot points in the linkage/wiper drive shafts? Second: Is the 91 Honda "Motor" really that much stronger/more powerful than the original Datsun Motor - - OR - - is the gearing on the drive mechanism the reason for the better performance on the Honda? (ie. gear reduction starters or more modern magnets in the motors themselves). Do you know how many amps each motor draws? Third: If the 91 Honda Motor Assembly uses the same output shaft - - - would it be possible to simply swap only the motor (wondering if the motor has the same input shaft???) .... That is to say take only the electric motor from the Honda and adapt it to the Datsun gear drive and wiring? Like I said - just curious.... FWIW, Carl B.

HI Jon: Received your input 10 Oct. 07, but we need your original engine serial number from the data tag under the hood. thanks, Carl B.

da.... that should be HLS30 62001... FWIW, Carl B.

Hi Ron: Is that a "seat bottom change notification" or is that a notice about the switches used? Nonetheless - The Seat Belt Warning buzzer was required for 1972 Production. So the seats with the wire springs went into 240-Z's beginning in Jan. 72. The VIN's started at HLS30 00001... 01/72. A few 12/71 production cars came with the springs in the seats - but no warning light on the fuse box cover... FWIW, Carl B.

There are two sets there... which one are you talking about? Carl B.

Hi Steve: I noticed it because I ran into the same problem. One of the brake lines from the master to the distribution block was totally plugged on the 73 BRE Z ... and I couldn't get it opened up... it was of course listed as NLA from Nissan... So a friend in Atlanta sent me a set he had already had re-Cad plated.... it looked like the set from CT and was of course the wrong one... So he sent me a second set and finally we found the one that would work (like your OEM line).... So it looks like they changed that line sometime before the 73's came out... I'd send the two lines back to CT, and ask them to duplicate your OEM line - and note that is the line for late 72's... That way they would have the model for both.. and customers could just send in a picture of their original lines so they would know which one's to resupply. good to hear your making progress at any rate... FWIW, Carl B.

From your pictures, I can't tell if you have a screw in the top hole of the left hand bracket or not. Nonetheless look at the difference in the mounting position of the two sides. the Right side is mounted correctly on the seat back - the left side is not. You need to rotate the top of the brack, on the Left side toward the rear of the seat, then screw it in place there. If there are no holes in the seat back - on the left side - that line up with the holes on the right side.. you have the wrong seat back.

Hi X-Ray: The tube coming down from the brake master cylinder to the distribution block... the one on the right in the last picture ...... looks completely wrong... What did you do about that? What year Z did CT think that line was for? Thanks, Carl B.

Hi Mauisnow13 I know the B pillar emblems say 240Z - that is not the question. Are the "Z's" solid flat chrome, or are they the "Z's" the style with a raised outline, and the center painted white? See images below - and look at the "Z"... BTW - the "A" pillar is at the windshield - the "B" pillar is at the rear of the door - the "C" pillar would be behind the side quarter window... actually it's the rear quarter panel. thanks, Carl B.

As you can see from the picture below... the 302 Green on the 260Z had far more of a silver hue or under tone, than the 113 Green on the 240Z. FWIW Carl B. Carl Beck Clearwater,FL USA http://ZHome.com

Although much belated... I wanted to thank Guus for providing such great coverage of the 2007 EAS.. Although our Z's didn't have quite the spectacular results they had last year, it is nonetheless amazing to see 35+ year old cars still being driven so hard... and providing their owner's with so much FUN. Thanks Guus: Carl Beck Clearwater, FL USA http://ZHome.com

Hi Greg: "The Z Car List" was terminated, not split up. After 10 years at Texas A&M the Sys.Admin. that supported us had passed away. The old server was on its last legs and the new management couldn't justify buying a new server for a non-University purpose. So we were loosing our free host and connection to the Internet. At the same time, participation on the e-mail based forum had dropped off to next to nothing. Everyone wanted to receive the Posts/Replies... but very few were actually participating in the discussions. As the Z Car Community itself split into Model Specific groups (is a HybridZ a specific model) , each with their own Web Sites and Web Based Discussion forums, there was simply no reason to continue with the e-mail based forum. A lot of growth and change took place during the 20 years the Z Car List was on-line. The Technology Life-Cycle you know..... Your always welcome to come visit any time you are in the area. FWIW, Carl B.

Hi Mauisnow13 Looking at the picture of the passenger seat in your Z - it looks like you might have the very rare plastic seat guards, along the bottom side/front of the seat. See if those guards are on both sides of both seats - and let us know what you find. Also, can you get a clear picture of the 240-Z emblems on the rear quarter panels of the car... I'm wondering if they are the very early "CHROME Z" or the later style Z that has an outlined edge on the Z with white paint inside the outline. Also would like to know if the 240-Z emblem in still on the rear deck lid, and what type it is. thanks, Carl B.

Hi JonnyRock: If you would, please look on the drivers door jam and let me know what the Date Of Manufacture is for your Z. Also, let me know what the original engine serial number is. Jon in Bellingham, WA has HLS30 01702 and Chet Riley in Mobile, AL has #01694. FWIW, Carl B.

HI Mauisnow: Looks like the wheels alone are worth the purchase price. Look under the hood, and you should see a Data Tag that lists the original engine serial number. The number on that tag should match the number stamped into the engine block, just below the #5/#6 spark plugs. Let me know what the engine serial number is - you may have one of the L24's with the six counter-weighted crankshafts. FWIW, Carl B.