NewZed

The fusible links would normally just melt, with a touch of smoke, maybe, if there was a short. So the sparking doesn't really make sense. The 12 volt reading is correct, as you described it, to the block. What you mean by "chassis" is unclear. In short, it's not clear what the problem is, besides some sparking. Not sure what you mean by "it".

yes its easy just s and l and the solenoid wire and the charge wire and the battery cables. you can ewven use a screwdriver if you want to avoid the solenoid wire

The basic problem is that the studs are commonly NLA. You have to find old stock, apparently. You can start at #175 here - http://forums.hybridz.org/topic/78123-subaru-wrx-sti-r180-side-axles/page-9 and again at #237 http://forums.hybridz.org/topic/78123-subaru-wrx-sti-r180-side-axles/page-12

Never heard of a "kit" for that. There's not much to replace. If the boots are okay, all you really need is a new clamp to hold them on. A CV boot clamp would work. All you'll really be doing is replacing old grease.

You can search around John Coffey's threads on the axles for the Subaru diff and you'll find some part numbers, I think.

If you decide to try the machining to make it work, you might look in to another heat treatment to get the desired physical properties, if you can't determine what you have now. Although I think heat treatment can change your dimensions.

It's the shape of the teeth and the grooves that will get you. I picked up a J30 diff because it has a 28 spline axle (just to mess around with, I know that the VLSD has la longer axle) and found that the stock Z axles were sloppy in the J30 and the stock J30 axles were very tight in their original home. Can't remember if I tried the J30 axle in the Z R200 or not. That's why I bring it up though,. It's more than number and diameter.

Sorry Joe. I knew there was another supplier out there. This is the one, right? https://whiteheadperformance.com/product/whp-billet-cv-300zx-z31-turbo-axle-companion-flange-adapters-27-spline-datsun-240z-260z-280z/

Have you stuck an axle through there yet?

That's a good find. Seems worth a look. The axle, at a stress riser, is where failure usually occurs at the hub. Their ad copy says "forged 5140" which seems to have some high stress uses, according to the internet. Cranks, for example. Not clear if they are cutting blanks from forged steel or forging the shape and machining though. Proper grammar would say "blanks forged from 5140...). Anyway. "Our Blank Output Flange is made from forged 5140 chromoly steel. " Number and diameter of splines and shaft won't tell you if it's a good fit for the axle though. You won't know until you try it. Spline shapes differ. You'll need to do some machining also, either a new distance spacer, or the flange, to fit the hub. Still interesting though. I'd spend $30-40 just to mess around with it.

Kind of looks like you didn't either. How would he know that Joe's out of stock if he hadn't contacted him? First post. Besides that it looks like he swapped his 240Z parts for 280Z and that's why needs 27 splines instead of 25. He confused the issue himself by leaving that out. Words....

What brand of header is that? The hot spot is at the junction of the four pipes. Maybe it's just a poor design with a a flow restriction and thin metal.

The pilot bushing, while small and simple (dull) and cheap, is very important. It supports the end of the input shaft. A loose pilot bushing can let the shaft rattle around. You might ask the shop. Any decent shop would know, it's a normal part of clutch replacement.

There's a nut on one of the shafts that's known to come loose. It affects shifting also though. Did you have the pilot bushing replaced when you had the TOB done? Also noticed in the other forum post that you said it makes the noise in the lower gears, but not 3rd and 4th. Might be meaningful. Good luck.

If you know some people with Z's or the same transmission you could take a ride and compare. I've had four in my car that all make the same noise, they all sound like they need work.. Did you find anything on the magnet when you drained the fluid?

Nobody said that Redline would help the noise BUSZED just made a point about thick oil damping the noise a little bit. You're not being very clear on what the noise IS,beyond a "rattle". A video might help your cause. To be more clear on this end, the bearing noise is more of a dull internal rumble than a rattle, that goes away when you press the clutch pedal. If you have a real, "bare metal shaking around" kind of noise, it could be something completely different. And Redline fluid isn't going to fix the bearing noise anyway. Edit - just saw your post on another forum where you call it a "chatter". Words are all we have out here, you have to pick the right ones and use them the right way, to create an image. Edit 2 - it also looks like you're getting your various suggestions confounded, like talking about Redline in this thread that never mentioned Redline. You're going to create a mass of confusion.

Fuel line modifications, among several seemingly small things. Read through the FAQ's on the L6 engine. Study the Z car terminology. For instance, we usually call the air flow meter an AFM, not a MAF. And an intercooler is a secondary item, not really necessary to "make the car running". http://forums.hybridz.org/forum/90-l-series/

I think that the later service manuals might mention that if there's a problem it could be a bad voltage regulator. Think I've seen it in the 280Z FSM's. If both needles go wacky at the same time it's likely that, you'd think. Picture from 1973 FSM.

Andreas is right, considering bore size. I was thinking of the classic N42, N47, F54, P90 head and gasket problem. L28 heads on L28 blocks. You have an L24/L26 head on an L28 block so an L24/L26 gasket might not seal the bore. Take measurements and consider coolant flow.

If there are no passages in the head the coolant has no where to go. And the head is probably more sensitive to coolant flow than the block. That would be my reasoning. Match the head, I'd say. Opinion.

This changes the situation. But, still, a condenser won't hurt. You might check your grounds and various connections too. Also consider just a low battery and/or weak alternator affecting the ignition system. The turn signals draw extra current and the Z alternators are known to be close to maxed-out at idle speed. Try revving the engine with the turn signals on and see if the dying needle fixes itself.

I've solved a twitchy tach needle on my 76 by adding a condenser to the negative side of the coil. It was a plain old alternator type, connected to the negative post. The early tachs are designed for the 6-volt system, with the coil and ballast resistor. The later electronic modules might just be too noisy for the early tachs. I'm not an electronics expert but I know that it worked for me, with a GM HEI module (the problem came back one day when the condenser/capacitor wire broke due to vibration), and it can't really hurt anything.

That resistance is probably fine. The E12-80 module has current control, I believe, it can handle it. The tach needle problem might just be a tach problem. Check the capacitor/condenser by the coil wiring. The tachs don't like electrical noise and the condenser is there to damp it. You haven't said what year car you're working with.

0.84 to 1.02 is the primary circuit resistance spec. on the stock 1979 coil. What's the resistance of the 8202? The odd behavior with the turn signals suggests other causes..

That's very common. It's one of the bearings in the transmission. Can't remember which one. Seems to be inherent to the design and the bearing that Nissan chose. Most make that noise. If it's really bad though it could be a sign of impending failure. If it just sounds like a rough rumbly bearing it's probably fine. If it's crunchy and poppy, maybe not.