Zed Head

Maybe the can of Seafoam was rattling when you revved the motor. I have actually spent a few moments in the past wondering what "that noise" was from the rear end of the car then realized it was the old beat up speakers behind the seats sliding back and forth...

Click through the choices in the link. You will get to a page that shows a positive and a negative option for the style and size chosen. I second (third, fourth?) the thanks for putting this out there. Much better than what is typically found in the auto parts store.

Never mind. Not a good discussion starter...

Didn't mean to stir things up with my KISS comment. The last S can be inflammatory and that was unintended. So Rocket88, you have options. Since you mentioned that the coolant was flowing along the head/block interface, you should make sure that you look closely at the thermostat housing. It might be starting there, flowing down to the interface, and just showing up between plugs 1 and 2. It's difficult to see up under there, a mirror might help. There are several sensors in the housing that could leak plus the housing gasket itself. Have fun.

Agreeing with the man from OZ... The original post described a very small problem. A "bit of a coolant leak." It goes away completely when the motor warms up. No mention of overheating, oil burning, etc. The post even says "no white smoke" so there is some awareness of the various bad head gasket issues. Just taking off the head can cost extra money and time, for gaskets, broken bolts/studs, possibly failing to secure the timing chain, etc. I would apply the KISS principle here.

You could try some of that "magic" leak stopping powder, like Bar's or other. I had a small external leak from the back of my engine and one bottle of Bar's stopped it.

You are probably supplying another ground path to the battery, through the brace to the mounting points, then on to the negative terminal of the battery. You might have a weak ground wire connection or corroded connection points. I think that the sparks imply that there is some resistance in your current ground path, from the engine to the battery. The main ground for the engine on my car is from the negative terminal of the battery through the heavy gauge wire to a transmission mounting bolt. It would be worth checking yours to make sure it is low resistance.

jacobmccabe92 might have some used... http://www.classiczcars.com/forums/showthread.php?p=327794#post327794

I have a 76 and a 78 parts car and they both have that ugly-looking thing. Zs apparently came from the factory like that, not sure what year it started. It's in the Rear Axle and Suspension section of the FSM, called a "damper plate". It must be designed to damp either vibrations or clunks, I would guess. By the way grantf, I went to see what year car you had and your About Me says that you don't even have a car yet.

My car ran about medium-rare over the winter but since spring is here has been running medium. Coming up the Highway 26 hill the other day I let it rev in 3rd gear just to listen and see how things sounded. It started getting pretty close to done though show I shifted up before I really cooked it. :laugh:

You might think twice about the universals. I replaced all of my half-shaft u-joints because one was bad, thinking that newer is better, but found that the old ones that were still good, were tighter than the brand new ones. I ended up putting two old half-shafts with original u-joints back in. If the u-joint is not loose or dry, it's probably worth leaving alone. You can regrease them by reinserting a Zerk fitting, if they are capped. To add to GreenZZZ's comment - I couldn't tell that my diff mount was bad until I got the cross member unbolted and pried on it. Then it was obvious. With everything bolted together, it's hard to get the leverage, and hard to see what's moving.

My switch was bad when I got my car, a 1976 model, and after reading through the manual and figuring out how it worked I realized that with a bad switch, the car just runs a little dirtier when it's cold. The switch advances timing when cold, I believe, to get it to run cleaner. It's only on the non-CA models. I could be wrong on the reason to advance the timing when cold, but either way, without the switch, the car just has the timing when it's cold that it would have anyway after it warms up. My car runs fine when cold, without the switch working. Once the car warms up, the switch doesn't do anything.

The master cylinder only pushes the pads on to the discs and the shoes on to the drums. It doesn't do any retracting or pulling back, so wouldn't be the cause of your wheels being locked. You should take the front wheel off and see if you can pry the pads and pistons back in to the caliper to get the wheel to turn. You might need new calipers or a rebuild. It sounds like the pistons have rusted/corroded in the bores. Same thing on the back. Take the wheel off and see if you can remove the drum. You will probably have to loosen the adjusting wheel inside, using a screwdriver through the adjustment hole. They tend to be very difficult to remove once they get stuck.

Just to tie this up and for anyone else that wondered, here are a few pictures. The resonator (actually an anti-resonator I believe, by definition?) does neck down a little at the inlet then back out at the outlet so does create a flow restriction. But the interior is pretty smooth. There are some holes in the interior but no "teeth" to create turbulence. For those interested in the esoteric Z stuff... (and of course, the obligatory shoe photo - Asics)

The water temp sensor tells the ECU how long to open the injectors. The colder it is the higher the resistance value. If it goes bad, giving infinite resistance, or you have a broken connection it will tell the ECU that your engine is stone cold and the ECU will continue to pour on the gas. Page EF-23 and EF-32 of the 78 FSM describe the test procedures (sorry, the 77 FSM is too hard to find things in). Measure across Pin 13 to ground. If you get infinite resistance you probably have a bad sensor or a bad connection. Resistance should be about 2.5 k-ohms at 70 F. 76 uses Pin 13 also so it's a good bet that 77 does too. The thermotime switch just cuts powers to the cold start valve if the engine is warm or if it's been cranked over recently, I believe.

Thanks for the insights ZCurves. I will try to avoid the Olds sound, but am not ready for Twice Pipes. Baby steps.

I have a complete original exhaust system from a 1978 Z that I am going to install on my 1976 280Z, non-CA model, to replace the original one, since someone smashed the exhaust pipe up against the differential when lifting, to about half volume. Plus the $30 O'Reilly's Cherry Bomb turbo muffler just doesn't sound right. Could anyone tell me what is inside the small "pre-muffler" up next to the transmission? The little mini-muffler. It looks to me like a place-holder for the California model's catalytic converter. Is it just hollow or does it create a flow restriction? If it's hollow I will just get a new muffler and install it as is, saving on gaskets and effort. If it is a significant flow restriction I will replace it with something else before installing. Thanks for any comments.

I have a flare wrench too but it has not always worked. Looking at those pictures, it may be vise-grip time. Once the points of the nut are rounded the wrenches are less effective. If you take great care in placing the vise-grips, and make sure the jaws still have good serrations, you can break those fittings loose with minimal damage. If you feel the grips slipping at all, stop and reset. And before you start, you should file the twisted off points of the brake fitting nut down flat to give a good gripping surface. The actual twisting of the wrench or vise-grip is 5% of the time involved. Getting the grip set is the other 95%. I have actually filed new serrations on my old vise-grips to get them to do the job. Clean the vise-grip jaws and the nut of any oil, grease or fluid. Any slippage at all is bad. Get everything set, double-check, then apply twisting force. If they are that tight, you may also bust a knuckle when it lets go, so have a band-aid ready. You can get pre-cut lines with the right fittings already flared on at most auto parts stores, for the short hard line. They are inexpensive. I made a bending jig with screws and wood but you can borrow real bending tools from the parts stores. Just take the old piece in to make sure you get the right style and length. If you decide that the hose is coming off no matter what, you could use a torch. Put a torch on the big end, watch out for bubbling brake fluid. Of course, once you bake the rubber hose, there is no going back.

sblake - I was joking about Tony D. By alter ego I meant the opposite of. From what's been going on over at Zcar I thought maybe someone had had enough and was stirring the pot a little bit. I meant no offense to Tony D, these guys aren't even from the same universe. If you were going to create two fictional characters to stir people up, these would be the two. When I read rzkas's posts I though "Is this guy real? Someone is messing with the forum." He breaks every rule of a good post - format, spelling, coherence, doing preliminary work - but he is just nice enough to get people to try to help him. Or was, I notice that his last post had 0 replies. ChrisS30 is the same. The first post was total immature nonsense, hard to believe that the person who wrote it could even find this forum to ask the questions. But again, just good enough to get some help. If these are fictional characters, the creator is a genius. I have to say that the Tool Shed concept over at Hybridz is a good idea. Keep the threads clean and purge the nonsense quickly.

I think that rzkas and ChrisS30 are one and the same. It's a test. Do I win a prize? (Maybe Mr. Tony D's, from Zcar, alter egoes?)

Vise-grips will work but you have to get it right the first time so you don't round the fitting end off. They do get freakin' tight and when they let go you'll think you broke it. Edit - it might help to take the hose end out of the mount so you can get a wrench/vise-grip on the big fitting and the broken end. Set the wrenches/vise-grips up so that you can squeeze them together rather than pulling on them.

Yes, that is the ECM. I have the same wires, non-connected. 1976, manual transmission. I looked closely when I was working on mine and decided that they weren't meant to be connected to anything full-time and just pushed them back under the cover. I could be wrong. That was quite a while ago. Maybe they are for diagnostics or a switch bypass.

It might have been the fuel pump switch in the AFM. When you turn the key to Start it is bypassed and the fuel pump is powered to start the car. When you let go of the key and it goes back to On, power to the fuel pump is supplied by the fuel pump switch in the AFM, which is allowed to close when the flapper opens in the AFM. If the contacts get dirty the power is not supplied and the car dies. It happened to me, with a new AFM. The car would start then die after about ten seconds unless I hit Start real quick (painful grinding noise) to energize the pump again and get the fuel pressure up. I had to clean the contacts to fix it. This was after I drove the car home with my fuel pump powered from my defroster circuit. Luckily I had enough wire to reach through the hatch and under the car. Sorry I didn't chime in sooner, you could have checked it out. But you were already pulling your gas tank, by the time I got here.

76 uses a contact switch in the AFM to kill power to the pump when the engine is not running. If you take the black side cover off, you'll see it, it closes when the AFM flap opens a few degrees. Move the counterweight and you can see it working. I have had the contacts get dirty and not close. Had to clean them up with a match book striker, they're small.

It's not the plate that goes between the transmission mount and transmission? That's what it looks like. Not sure what you mean by "lined up."