Zed Head

I think you might be better off if you just spent a little time studying the system. It's actually super simple. Just think of two pistons that are connected by the hydraulic tube, that move the same amount. Then adjust the metal pieces on each end (the slave cylinder rod and the clutch pedal linkage) so that there is very little play in either. Make sure the slave cylinder piston is starting from just off the bottom of its stroke (described by EuroDat above). Make sure the clevis pin and the hole in the clutch pedal aren't worn out (they do wear out, causing lots of slop). That's pretty much it, no FSM needed.

Rockauto shows .030" over as available. RockAuto Parts Catalog In general, I've heard that if you go outside recommended that you should have the remaining cylinder wall thickness measured. Some blocks can take it, some can't. But 0.120" seems way over recommended, I don't think that's possible.

There are only two basic things you need to work with on the clutch hydraulic system - starting point and travel. The travel is determined by how the master cylinder's movement is transferred to the slave cylinder. The starting point is determine by the mechanical components. I don't know the spec. on travel but the posts above suggest it's about 35 mm or 1 3/8". If you're only seeing 1/2" of travel, it's either because the rod from the pedal to the master cylinder is moving without pushing the master cylinder piston, or the master cylinder piston is moving without pushing fluid. The slave cylinder is self-adjusting due to the internal spring, so it's not really an issue unless it's leaking. I left some detail out but that would be my basic starting point. To reiterate - if the slave cylinder is not leaking, it's not your problem. It only responds to the fluid being pushed in to it. If your not getting full travel, it's because the mechanical linkage is not adjusted correctly or the master cylinder is leaking internally. Blue must have been having a bad day. He seems yo be ignoring the fact that the specs. that the Asian companies use are set by the their "Western" company contractual counterparts. In other words, if your "Made in China" part has problems it's because your American company is making profit at your expense. There are many many high quality products made in Asia. Nest time you're looking at your fantastic picture quality big screen TV, amazed at today's' modern technology, look at where it was made. Probably China.

You should be posting in the Classifieds section. There's a link at the top of the page.

You might consider that taking the engine apart is for your learning experience but buying a used, good condition engine (they are out there) to put back in is the economical choice. If the head gasket is new that means the IPO has been in there, which is not a good thing. You've had a poor lubricant running through the engine so there's probably extra wear on various bearing surfaces. You have a variety of broken parts. It's not you vs. the engine anymore, it's you vs. the PO's errors.

So is the popping and backfiring still there or does it run poorly in a different way? What's the current state of engine operation? You might have problems masking problems, or a problem that comes and goes which is what your first post suggested. If the engine runs well sometimes then you should probably hold off on big things like manifold gaskets. It's unlikely that they would vary between bad and good.

On #2, the stalling, I would say that your AFM fuel pump contact needs a little adjustment, or that you have a vacuum leak. If the contacts are off a little bit, a low idle will cut power to the fuel pump when air flow through the AFM lets the vane close too much. Bit in your case you say that you have power to the pump when the key is turned on, which is not the way the factory built them. If you have fuel, you should be able to drop your idle speed down below 1000 RPM easily. The jumpy tach and the cut out could be tied to the ignition system. What is this "upgrade"? There are many varieties.

There might be a misunderstanding here on the details. The contact switch in the AFM closes (makes contact) when the AFM vane (flap) is opened. This allows power to the relay which then powers the pump, assuming that the initial power sources are correct. If you take the black cover off of the side of the AFM you can see the mechanism. I've had the AFM contacts get contaminated (on a "new" MSA AFM) to where they look like they're touching but they're not really making electrical contact. I had to give them a buffing with a match box strike pad to get them back in order. You can check that the contacts are closing by testing for continuity at the AFM with it removed or at the EFI relay plug (it takes some study to figure out which wires go to the AFM contacts). I would check those AFM contacts before going too much further.

It's looking more and more like you either bought your car from someone who thought they knew what they were doing and was way over-confident or you got scammed. Since you've found the source of the water/oil leaks maybe you don't need to remove the head. Can you tell if it's ever been removed before (new gaskets, etc.)? If not, you might be able to get back in to running shape with just the timing chain cover work.

When you came back with AFM testing I assumed that you had fixed the fuel pressure drop problem. I'm guessing now that you did not. The EFI must have proper fuel pressure to work correctly. There's no way around it. 26 psi is probably the lowest pressure number you should ever see on these engines. Don't get distracted by the new pump or the recently cleaned tank. Something is still wrong with your fuel system.

The popping is a typical sign of lean mixture and the fact that it's worse as it gets cold fits. The fuel pump contacts are only for the relay and will not cause problems since yours runs all the time. 60 ohms is about right for a relay, but in your case the relay is not being used so it doesn't really matter. 60 ohms is also about right for the AAR citcuit. That is the resistance of the heater wire inthe AAR. looks good. What you need to measure is Pin 8 to Pin 6 (180 ohms) and Pin 9 to Pin 8 (100 ohms). Measure at the ECU connector if you can. IF you're using the 1980 EFI Handbook, they would be tests #1-3A 1975-78, and test #1 3C 1975-78 Those are the circuits that control the fuel mixture. I have a theory that as long as the ratio of those two is 1.8 the AFM will work correctly, but if you're way off, typically the engine will run lean, causing popping and backfiring.

The fuel pump provides the pressure and the fuel pressure regulator (FPR) controls it, by bleeding off excess. You want to measure between the filter and rail so that you read the pressure that is in the rail at the injectors. Since the FPR is in the middle of the rail the only place to connect the gauge is between the filter and the rail. The pressure is not directly dependent on load but the FPR does adjust pressure based on intake manifold pressure. That's what the vacuum hose to the FPR is for. When you first measure the pressure, pull the hose off of the FPR. The engine will run rich but the reading you get will be the baseline reading. It should be about 36-38 psi. Reconnect the hose to the FPR and go for a drive. The fuel pressure should vary between ~28 psi on the low end (it could go a little lower or a little higher but it should definitely be lower than 36-38 psi). When you hit the throttle the pressure will increase as intake manifold pressure increases (vacuum level drops). When your problem happens you will probably see the pressure drop down to the low 20s or less, if the fuel pump or fuel intake is the problem. Fuel starvation.

Define the current state of the idle. "Not right" doesn't give any clues about what's happening. Have you confirmed that there are no leaks in to the intake system? All air must pass through the AFM. Any leaks at all will affect the way the engine runs. Even leaving the dip stick out will have an effect.

Looks like a gear puller helps, #146 - Subaru WRX STi R180 Side Axles - Page 8 - Vendor's Forum - HybridZ

It's reddat. Well-known. He is karma for people who don't use internet search tools. Funny that the ad only shows a picture of a drawing, not an actual part. I'm pretty sure that he just buys parts from MSA, BlackDragon and the local parts stores and resells them. He may not even buy them until someone buys on eBay. Check out this $125 O'Reilly pump for $174.99. Used. http://www.ebay.com/itm/Datsun-280z-280zx-Fuel-Pump-NICE-/321254685937 http://www.oreillyauto.com/site/c/detail/DLP0/FD0035/02535.oap?year=1976&make=Nissan&model=280Z&vi=1209226&ck=Search_fuel+pump_C0401_1209226_2513&redirectkeyword=fuel+pump&pt=C0401&ppt=C0025

IF you can keep the engine running while you see low pressure, one way to check the FPR and pump and/or the fuel tank is to squeeze the return line. If pressure increases the problem is the FPR. It's not doing it's job. If pressure does not increase then there's a problem with supply, either the tank or the pump. If you determine it's supply, you'll still have a dilemma since the problem only happens when things are warm. But you can let your fuel pump run for hours with no issues as long as your battery holds up so you could follow-up by trying to recreate the problem with the engine not running, in the garage. Just keep narrowing things down until you have one possibility.

These things seem to be typical of either a bad fuel pump (over-heating) or crud in the gas tank (clogging the inlet then floating away when stopped). If you go with a gauge kit and run the hose out of the hood you'll be able to watch pressure while you drive. If you put the gauge in the engine bay you'll have to jump out and open the hood and hope the engine stays running. Something to consider.

Can't tell if you guys are driving 240K's or 240Z's but the 60 amp alternators from some of the late North American market 240Z's, 260z's and 75-77 280Z's used a 60 amp alternator with the external voltage regulator. Should be a straight bolt-in.

The air has to come through the AFM. If you run a filtered external source you'll run way lean when the valve is open. The valve should be placed where the AAR was. You could probably plumb in a later model AAR that might have a little more engineering in to it to make it more robust. But the basic design has lasted many years.

I live in the Portland area and I removed my my cold start soon after getting my car. I don't notice any problems starting my engine. On the other hand, when I had a fuel pressure regulator that leaked fuel pressure I did notice extended cranking times. The "crank and crank and crank" description sounds like it might be more than just a fuel pressure problem though. Could be a combination of fuel pressure weakness and a weak pump. Leaving a gauge on will provide a lot of information. Check the pressure before trying to start and watch it while cranking - where did it start and how long did it take to build. The engine might also just need a tune-up. Weak spark can cause extended cranking, trying to light up cold fuel. But with these engines, knowing fuel pressure is never a waste of time so it might as well be done first. With fuel injection, proper fuel pressure is critical.

Do you have a gauge yet? Do you have any plumbing experience? If you are not handy with threaded fittings and making them leak-proof you should probably buy or borrow a fuel pressure measuring kit. It will come with a plastic T-shaped fitting and a short piece of hose that are inserted between the filter and the fuel rail. The old fuel hose will be difficult to remove and may need to be cut off. Gas will spill. If you need to cut the old hose off you can just cut it and insert the gauge then replace the hose with new when you're done. Quicker. If you know how to work with fitting you can buy a gauge and fittings and fabricate your own gauge system. Depending on the price of brass fittings at your location it might be cheaper to just buy a gauge kit at a parts store. The hose is 5/16" internal diameter.

Kind of depends on what the $20k is going to buy.

My understanding is that the condenser was originally added to damp excessive arcing across the points to make them last longer. Then some electrical wizard discovered that they also made for a stronger spark through some sort of electrical oscillations,allowing the coil to charge faster. Read up on Kettering ignition systems, it's pretty interesting stuff. So when your condenser went bad, you got a weak spark that also wore your points out faster. Probably why a set of points usually comes with a condenser (capacitor) included.

These guys are right, and to be clear I was just offering things to look at and another perspective. Considering how well emulsified the oil-water blend is it's possible that the OP or someone drove the car for quite a while with a small coolant leak. And when the engine is running the crankcase is under vacuum while the coolant system is under pressure so a small passage from coolant to oil in the HG might pass that much coolant. Who knows. As you're taking things apart don't clean things up. Leave the grime and old gasket material in place so that you can see signs of damage.

The distributor is not an issue but make sure that you get the oil pump shaft installed correctly. That's where the problems with distributor adjustment happen. The procedure is well-described in the Engine Mechanical chapter. Interested to see what you find, take pictures. You might have to remove the engine to replace all of the core plugs, I've never done it.