Zed Head

More on this case history of a 240Z re-entering the market - Down to $5,000, from $8,000. Original cost = $2,300, plus any extra title transfer/transport fees, etc. http://portland.craigslist.org/mlt/cto/2473492309.html 71 DATSUN 240Z 4-SPEED ...(same text as above)...$5,000 503-995-6692 DATSUN NISSAN Z 240 280

Did it work before? With the electronic ignition? Or is the ignition system new and has created the tach problem?

It looks like a ground wire, probably for connection to the block (based on it's position and size). If you have a volt/ohm meter you could check for continuity to the negative cable terminal. If it doesn't run to the negative cable, then turn the key to On and check for voltage.

Wow! I thought this grammar form was US-based only. Fascinating. Are you from New Zealand or did you move there from the States. I'm not kidding, seriously, I am interested.

Just for fun. He's down to $5,900 and has changed the ad to show second owner. Still looks like a nice car. A new CL posting - 71 DATSUN 240Z 4-SPEED , 83000 ORIGINAL DOCUMENTED MILES. NICE INTERIOR AND EXTERIOR. STRAIGHT BODY, AND BUMPERS. AC WITH PUMP. ALL LIGHTS IN AND OUT WORK. ALL GLASS IS GOOD. DOORS OPEN AND CLOSE NICE. ALL GAUGES WORK INCLUDING THE CLOCK. ORIGINAL POWER ANT. WORKS. ORIGINAL WOOD STEERING WHEEL. CAR IS ALL ORIGINAL EXCEPT WHEELS AND TIRES. TIRES HAVE 80% PLUS TREAD. RUNS AND DRIVES GREAT. DRIVES LIKE IT SHOULD NICE AND TIGHT. WELL KEPT AND MAINTAINED. STILL HAS ORIGINAL PLATES AND TAGS. ADULT SECOND OWNER. $5900 503-995-6692 DATSUN NISSAN Z 240 280 http://portland.craigslist.org/mlt/cto/2473492309.html

You didn't say if you're running carbs or EFI with your L28. If you're running fuel injection, you need a high-pressure fuel injection pump. One for or from a 1975 and up Z car would work, 1975 - 1978 would probably fit your car best. If you're running carbs you need a low pressure pump, or, depending on what year L28 you have, you might be able to install the mechanical pump. Maybe, I don't know for sure. Look at your old engine, you'll see the mechanical pump on the front of it.

Check the contact switch on top of the steering column also (or close, wherever the headlight switch stalk ends). The tiny circuit board can get loose and let the contacts lose contact. You can unbend the four crimped hold-downs, pull the board and clean the contacts. When you put it back together, crimp the hold-downs extra tight. If you want to check it before taking it apart, just press down on it with your finger and see if the lights start working. The dimmer switch that beerman mentioned should also be looked at. You can spray contact cleaner in to the switch area and work the lever to clean it up. Or you can attempt taking it apart. I had the loose column switch go bad on a 78 parts car, and a dirty dimmer on a 76.

I used a couple of greased putty knives to get the front bushings in. One one each side, and press it in. They weren't too big by 2 mm, but the concept should still work to give some leverage to compress the polyurethane. Drywall mud blades, putty knives, any thin flexible metal should work.

There's really only a couple of things left, if you're sure that al of your parts are Nissan stock and correct for the year. Are you running the stock ignition system, no dual spark or MSD type? I only ask because the ECU fires the injectors after every third discharge of the coil. That would probably show up as a higher tach reading though,since the tach is on the same circuit. Does your tachometer work correctly? It's usually a bad idea to replace parts without being sure but for $10 you might be able to at least look at another ECU. This guy is in your neighborhood and has your ECU #, I believe, for $10. He's just cleaning house. Worth a thought - http://forums.hybridz.org/index.php/topic/100893-ecu-blowout-10/page__p__945646__hl__ecus__fromsearch__1#entry945646 I have read of ECUs going bad and running rich, but never for as long as you've been driving. I don't know enough about the inner workings of the injectors to guess what happens to them when they get really worn. Maybe the flow rate goes up. That's really all there is to the system - ECU opens injectors for a "calculated" amount of time (based on temperatures and other inputs) and fuel flows out of the injector at an assumed rate. I just thought of one more option and again I don't know what would happen if, but the TPS has three positions, idle, cruise and full enrichment. Maybe your TPS is stuck on full enrichment. The ECU thinks that you have the throttle close to wide open. It could also be stuck on Idle, I suppose, since that is also an enrichment position. Again, probably best to test at the ECU. The pin numbers are in the Fuel section of the FSM, and are the same at the ECU plug. I would do that before anything else, it's easy.

Here's something from left field - is it possible that someone from the past installed turbo injectors or some other higher flow injector? That would lead to lots of extra gas being squirted, even though everything is right on. I believe that there are ways to tell them apart but I don't know what they are. And are you sure about the mileage? The inside of your tail pipe should be all black and sooty with that much gas going through there. Mine has a light coating, still running slightly rich, at ~20 mpg.

He's edited this CL post down to $6500 already. 1971 DATSUN 240 Z ONE OWNER 503-995-6692 - $6500 (SE PORTLAND) Date: 2011-06-28, 12:47AM PDT Reply to: see below [Errors when replying to ads?] 1971 Z CAR NICEST ONE IN TOWN EVERYTHING WORKS EVERYTHING.FACTRY AC,DUAL SIDE DRAFT CARBS,FOUR SPEED,YOU NAME IT IT HAS IT,# MATCHING,ALWAYS INSIDE,VERY WELL LOVED BUT NEEDS A NEW HOME,DONT WAIST MY TIME IF YOU DONT HAVE CASH DEPOSIT NO TEST DRIVE,CAR WILL NOT BE SHOWN ON RAINY DAYS,(503)995-6692 ,KEY WORDS:JEEP,WRANGLER,CHEV,DODGE,FORD,DATSUN Z,240,260,280,Z CAR,TOYOTA,NISSAN,HONDA,SUBARU,CAMARO,NOVA,CHEVELL,$6500/OBO/TRADE?(503)995-6692 CALL I MAY TRADE YA CASH IS KING MAKE ME A OFFER 503-995-6692

You are right, Nissan went to the -11, wide-gap plugs in 1977, presumably to match a stronger ignition system. My ignition system is modified from the original 1976 specs. And I should run the resistor plugs (BR instead of just , to go with my resistor wires, to avoid electrical noise problems with my EFI system and ignition. My original post is more about what's going on with the highly popular NGK spark plugs. In today's auto parts stores most counter people won't know what a BR6ES or BR6ES-11 plug is. They might not even know the NGK brand. Knowing that NAPA part number 7910 = NGK B6ES-11 or NAPA 3824 = NGK BR6ES-11 might help someone out. Most store's systems can't find the NGK part number, they have to look in a separate paper cross-reference book, if they can find it. Even on MSA's web site, you can't tell what NGK part you're getting, only that the plug they have listed is for your year and model.

thanks. I just figured out that that site is actually a front for www.sparkplugs.com. The disclaimer is at the top of the page. Here's the real NGK site - http://www.ngksparkplugs.com/index.asp Same stock numbers though.

The resistance should not read the same unless the engine is completely cooled down, like overnight. The air sensor is in the AFM and reads air coming in to the engine. The water sensor is in the thermostat housing and reads how hot the engine is. It looks like you're making progress though. All of these small things will add up. That is a crappy photo, but the AFM does look pretty normal. A dab of silicone is put on the screws at the factory. If it's broken it's been tampered with, if not, maybe not. Have you checked the cold start valve? Besides the six injectors, it is the only other place for fuel to be pumped out of the gas tank. Since it's summer-time, you could just remove the fuel line to the CSV and plug it. Don't just stick a threaded bolt in the hose, there's 40 psi behind it. If it has been leaking, you'll see a change. Or you could pull the valve and see if it leaks. 10 mpg is way low. There's something big going on. Are you sure that your odometer is working?

It probably does. I just threw some random thoughts out. You wouldn't know it was NGK, on the first NAPA search page, "Standard Nickel" is the big print. https://www.napaonline.com/Catalog/Result.aspx?Ntt=spark+plug&Ntk=Keyword&Nty=1&N=599001+101979+50018+2018016 NGK used to be a big name top brand, but they don't seem to be so hot any more. The auto parts stores don't have them in stock, or they have to special order them. Even on the NAPA site, you can't tell if it's a B6ES-11. Thought some people might be interested for future reference.

85? And you thought you were going 70? What's wrong with all these slow people?! And just a warning? Not bad.... Can't find a picture of the "German-style" plate and don't know what it is? Do you have one? Oregon requires a front plate and my new one, bought because the old one had been crushed so may times, has already been crushed again by the guy at the tire store, driving up the lift.

I was going to buy some NGK B6ES-11 spark plugs but none of the local parts stores had them on-site. Searching around the internet I found that NAPA sells a "Standard Nickel 7910" for the application but doesn't list the B6ES-11 number. A little more Googling and I see that NGK.com has 7910 as stock number but B6ES-11 as the part number. This might be common knowledge but I thought it was interesting. Did "Standard Nickel" buy the NGK brand name? It's not clear to me what's going on here. https://www.napaonline.com/Catalog/CatalogItemDetail.aspx?A=NGK7910_0275400672&An=599001+101979+50018+2018016 http://www.ngk.com/results_cross.asp?pid=7910&x=0&y=0

Gary S., I'm surprised that you found that. He put a space between 240 and the Z so it doesn't come up if you search for 240Z. Karma?

The key test at the ECU connection is for the water temperature sensor. My engine loses 1-2 mpg during cold weather just because the engine never really gets hot. At the ECU, measure resistance between pin 13 and ground. Compare the value you get to the table attached. Notice that as the resistance goes up, the ECU thinks the engine is cold and adds more fuel. Corrosion or oxidation at any of the connections between the ECU and the sensor can increase the resistance. The air temperature sensor does not have as much effect but you might as well measure it also. Measure between pins 6 and 27. It's the same type of sensor so the same table can be used. If you measure before you drive the car for the day, then the sensor should be at ambient temperature. If one reading is correct, the odds are the other temperatures will be also.

Why did you do this? Did you have to adjust anything to get the engine running decently afterward? Unless you blocked the PCV port you would have a large leak in your intake system, probably requiring at least some idle adjustments just to keep it running. Seriously, wondering what the purpose of the change was... The exhaust coming out is "blow-by", typical on older engines and one of the gases the PCV (Positive Crankcase Ventilation system) is designed to remove and burn.

sparrow, I think you missed the point (actually several points). The air bypass volume is large in comparison to the volume of air passing by the throttle blade at idle. But it's tiny in comparison to the volume of air passing by the throttle blade at higher RPM. Check out this site - www.zcar.com . It will probably offer you more enjoyment, and fit your style better.

Here are a couple of links I saved from when I was looking at an upgrade. http://forums.hybridz.org/index.php?showtopic=49864 http://forums.hybridz.org/index.php/topic/67531-ac-delcogm-alternator-swap-part-2-cs144-installation/page__p__634683__hl__alternator__fromsearch__1#entry634683 Search cgsheen or bjhines on the Hybridz site also, you might find some info. I think that one of them is using the CS130D alternator,which is supposedly the state-of-the art and a little smaller than the CS144.

Do you mean "cut" instead of "spliced"? Spliced means connected to another wire, generally. It looks like your white with red stripe wire has just been cut, but not connected to anything. The VR just prevents over-voltage. The alternator supplies the voltage. If your lights are dim and get to normal brightness, that implies a weak alternator. If the lights are fine but get very bright when revving, you might have a bad VR. The best way to tell is with a volt meter while the engine is running.

What is a "J mount" alternator and what "upgrade" qualities are you looking for? The typical change for your 1975 car might be to an internally regulated alternator but all it really gets you is one less component, the external regulator, and the benefits of solid state regulation over the mechanical points of the external regulator.

No problem. Thanks for getting back with the solution. Now I know for sure what happens if you connect two regulators in series.