NewZed

Here's one source - http://www.datsunstore.com/advanced_search_result.php?keywords=fusible&osCsid=b0c32fe5fecd13a94597e8149bc5a3fe&x=0&y=0 Assuming you found the short?...

Either should work. Are you sure the coil is good? If you had a shorted coil, you might get a hot module and no spark. Check resistance across coil + to coil -. Most coils are in the 1 - 3 ohm range. Another way to test your coil is by connecting coil + to 12 volts (switched with the key On or a direct from battery), placing the coil output (big main wire) ~.040" from ground, then tapping coil - to ground. Each tap should give a spark. I have tried that, and it does work. If you do it while the coil is mounted in the car, you'll be testing your ground back to battery also. Also, make sure that there's not a problem between the coil and the spark plugs. You might have everything up to the coil output, but a problem between the coil and plugs. It would be nice to confirm that your FIDLE signal is switching from zero to five like it should also. You might be able to see it with a voltmeter and turning the distributor but I assume it's a fast switch. Maybe the MS datalog shows what it's doing while you're cranking? If you can isolate each component and confirm it's operation, the answer will show up. It's just a good general way to problem-solve.

What happens if you disconnect G and W and leave B at 12 V and C at coil -? That would be the typical state for the module in its intended use. From this point, you should be able to connect G to ground and then touch W with power to get a spark. Each touch should take the G-W circuit from zero to positive which should give a spark from the coil. I haven't tried this but in theory that's how the module works,and that's what you're trying to do with MS. Isolate the module from MS, see if it works, if it does, then you can focus on getting the right trigger to it from MS.

I don't know a bunch about Megasquirt but I have read a little on the HEI 4 pin module. It is designed to control current flow to the coil, then kill the circuit when the G and W wires see voltage go from negative to positive from the reluctor in the distributor, causing the coil to fire . I don't think that G and W are designed to see a constant voltage/current flow, just the transitory "spike" from the reluctor in the distributor, every time the rotor passes the pickup. That's might be why it's getting hot. You might try a bigger resistor before pin G. The module is designed to trigger on very small voltages, less then one I believe, and up to very high. But I don't know that it will work with a square wave setup like you're trying. I think that the Bosch 0 227 100 124 might be a better choice for what you're doing. Described here - http://www.megamanual.com/ms2/Bosch_124.htm

How to determine if your camshaft and chain is installed correctly is described in the Engine Mechanical section of the FSM, with illustrations. All you have to do is turn the engine in its normal rotation direction and stop it at TDC, then eyeball the marks. It takes minutes. While you have the engine at TDC you can also check the rotor in the distributor to see if things are correct there. It should be pointing at a spot between straight ahead and the left headlight. Put you #1 spark plug wire where it is pointing, then install the rest in order. These two things are critical to getting the engine to run, but are very easy to confirm.

You don't say if it used to work or if this is a new installation. If it won't go in to reverse it's most likely a clutch problem, it's not disengaging. When you do get it in to gear (start it with the clutch pedal down, in gear), does the clutch engage when the pedal is way down by the floor? That's a sign of hydraulic problems. Master cylinder, slave or more bleeding. I have had a slave cylinder go bad within a few months, part quality is iffy from the big parts stores. Check inside the boot on the slave for fluid.

The FSMs are out there, on the xenon site.

Something to look forward to - http://www.bbc.co.uk/news/science-environment-13160950 Here's an excerpt in case the link doesn't last - Lasers could replace spark plugs in car engines By Jason Palmer Science and technology reporter, BBC News Laser-based spark plug (Takunori Taira) Two or three lasers are focused to ignite fuel in more than one place Continue reading the main story Related Stories Scientists build first anti-laser Lasers can act as 'tractor beams' Car engines could soon be fired by lasers instead of spark plugs, researchers say. A team at the Conference on Lasers and Electro-Optics will report on 1 May that they have designed lasers that could ignite the fuel/air mixture in combustion engines. The approach would increase efficiency of engines, and reduce their pollution, by igniting more of the mixture. The team is in discussions with a spark plug manufacturer. The idea of replacing spark plugs - a technology that has changed little since their invention 150 years ago - with lasers is not a new one. Spark plugs only ignite the fuel mixture near the spark gap, reducing the combustion efficiency, and the metal that makes them up is slowly eroded as they age. Continue reading the main story “Start Quote In the past, lasers that could meet those requirements were... big, inefficient, and unstable†Takunori Taira National Institutes of Natural Sciences, Okazaki But only with the advent of smaller lasers has the idea of laser-based combustion become a practical one.

I put a 78 5 speed in to a 76 and it dropped right in. Assuming that you have the the 4 speed manual in the 76 now, it should be a straight, no extra parts needed swap. The transmission housing and even the first 4 gear ratios are identical. The drive shafts are the same. The rear differential ratio should be the same between the two cars also, so no need to swap speedo gears. Everything should be identical, except you will have an extra gear when you're done.

Interesting car. The title of your post scared me though, I thought maybe Brett Farvre had a new hobby...

I've only been inside a few engines. But that doesn't look like factory honing crosshatch, does it? It looks more like someone honed a worn engine with one of those ball honers. Just wondering. I thought that detonation led to broken ring lands and that broken skirts was more a fatigue/high rpm problem. Maybe your oval bores led to the piston skirt breakage. Thanks for the pictures.

I have heard the same. But I have a PDF copy of a 1976 Service Bulletin (Vol. 23) that says "Cylinder Head Intake Valve Seats - The material has been changed to increase endurance reliability." There might have been more improvements after that but I've not seen it documented. If the head is off of a 76 at least you'll have "increased endurance reliability." I've never read a report anywhere about excess wear or galling on the valve seats from someone running today's unleaded through an old engine. It's an interesting factoid but not much backing to it.

Still not clear why you want to do this. Can you explain?

The discussion is really just about having the calipers either behind or in front of the struts right? What is your logic behind thinking the calipers would work better in the "Z32" position? The look is subjective but how they work should have some thinking behind it. Curious...

This one, the third Pinned thread in this forum is not enough - http://forums.hybridz.org/index.php/topic/98897-step-by-step-coilover-conversion/ ? It looks full of pictures...

Are you sure that the wires to the alternator and regulator in the car are connected properly? Plus a good ground to the alternator case (check with ohm-meter)? And fusible links are all intact? The auto parts store testers are wrong occasionally. You should test with a volt-meter (not the dash gauge) at the battery, in the car, at idle and higher rpm. What is your Charge Light doing?

You mean I could have just suggested moving a wire from negative to positive, without all the extra writing, and looked genius?! An opportunity missed...

Those are both positive power supply to two different components. Two different circuits, with two separate fusible links for protection. Don't connect either one to ground. I gave you the wrong page number above. It's page EF-26, not 36. Not sure why you don't want to take a look. Every time I look through there I learn something new (one reason I like to browse the forum). Those are the fuel injection harness fusible links. The diagram shows that one feeds power through the EFI main relay (72 in, 43 out) to the dropping resistors and the other feeds through the same relay to Pin 10 on the ECU (71 in, 10 out). So you should be able to check the circuit to the relay, through the relay and to the target. You won't get power to the targets until the relay is powered up through the ignition relay. But you have power to the injectors so you know at least one side of your main relay works correctly. Check for 12 volts at the Pin 10 connection to the ECU for the other half. There's a good diagram of the main relay in there also, with the pins numbered as referenced above. I would check continuity from Pin 1 at the ECU to the negative post of the coil. There's a resistor in-line but you should still have a circuit there. If Pin 1 doesn't see what's happening at the coil, your injectors won't fire. I'll leave you alone now.

http://www.datsunstore.com/product_info.php/cPath/37_157/products_id/1026

I am definitely not an expert on the Datsun EFI system (still learning) so can't really answer that question, but I would recommend moving on to the wiring diagram in the 1978 FSM. Page EF-36 shows the ECU, the relays, the power sources, injectors, cold start valve, etc all on one page. Just a quick look shows that Pin 10 gets its power from the electronic fuel injection main relay, which gets it power from the ignition relay. With the diagram and your meter, you should be able to back track to the power sources and make sure that you have good circuits. Be aware that your fusible links can be bad with no external signs. They're designed to contain the melted wire inside the silicone cover. You might check power at the end of those fusible links (the two green wires in your picture) to be sure they're good. The dropping resistors won't show a voltage drop until current is flowing. So you'll get 12 volts on either side of the dropping resistors if they're intact, engine not running, key on. Good luck. Download that FSM, it's broken up in to chapters, easy to use. If you're using the EFI Bible now it's the logical next step, it's more specific to the model. p.s. to the others on this forum who know the EFI system very well, feel free to add any thoughts or corrections.

Here's a link with some good pictures of the later 5 speeds, including the Borg Warner. If the shifter hangs off the back on a cylindrical mount and it's a 5 speed, it's one of the FS5W71Bs. http://www.az-zbum.com/information.transmission.shtml

Power to both terminals is correct. The ECU grounds the circuit, energizing the injector solenoids when the ECU sees the pulse from the negative side of the coil on Pin 1 at the ECU. Check that Pin 1 is getting the signal from the negative post of the tachometer. The tachometer has to be installed for the Pin 1 signal to get through. You might be starting on the cold start valve which only squirts during Start, but not firing the injectors.

I found the same thing with the ECUs. I found that 76 and 78 have the same part number but 78 won't run a 76. The pins are different (look at the pins on the ECUs if you have both). I've also found that my 78 ECU doesn't match the 78 FSM wiring diagram (the cold start valve circuit and a wire to a relay were different if I recall correctly). Did you bring all of the relays over too? That would be quite a job to swap the complete wiring harness. 1978 used more relays and less ECU to control some functions. You might take a look at the wiring diagrams between 75 and 78 and see if you need to add some relays or do some custom wiring. The Engine fuel section has some good breakouts of the ECU wiring. You can get both FSMs from the xenons30 web site -http://www.xenons30.com/reference.html If it starts, but won't run it might also be the fuel pump safety circuit, which is different for 1978, using the alternator or oil pressure switch to keep the fuel flowing.

What year is the car that you put the 78 gear in to? Did you change the wiring harness also?

Is it an LSD? I see the finned cover. That might narrow your options. If you're careful, you can put whiteout on the axle shafts and the pinion, turn the axles in the same direction one turn and count the number of revolutions of the pinion shaft. It's hard to estimate 3.7 from 3.9 but it is possible.