Mark Maras

I'd test it before prying those tabs back and opening it up. I broke a tab on mine.

At the Atlanta Z-CON, Charles and I talked with Matsuo-San when that question came up. As I recall he said that joint was intended to flex. The consequence of a stiff C-pillar was the A-pillar flexing instead with the possibility of a windshield popping out. @Patcon What do you remember of this conversation?

"It sounds like the drive shaft is gonna come up through the floor" is no exaggeration if the nose of the diff. is lifting and falling. With the help of a friend inside the car, position yourself so you can see the front of the diff. A mirror may help. Pull the parking brake on, start the engine, put the trans in first gear, and SLOWLY release and slip the clutch. Look at the diff. nose to see how much vertical movement there is.

I agree. In the beginning, this problem looked to me like it was a distributor cap, rotor, wire, or spark plug because it was only fouling one plug. It was either that or an internal problem. Countless plugs, new wires, cap, and rotor haven't made much difference but just to put my mind at ease, swap a plug wire with #4 and see what happens. Be sure all the wire connections are on all the way and secure. My son's Subaru had a plug wire that kept backing off the plug. He cured it by lubing the inside of the boot with dielectric grease. The boot slid all the way on the plug with grease.

Out of principle. The improvements? may have started with the automatic choke or possibly starter solenoids. Caveat, I drove a 39 Chev pickup for a few years.

I don't foresee any major problems. I'd also want to strip the vehicle of all the extraneous B.S. they've added to newer cars in the name of improvement.

I don't remember any access to the trim screws from the front. It was always a PITA to dig the mud out of the screw heads in the headlight bucket but I always had to go in from the backside.

Refresh my memory. What were the compression readings the last time you did a compression test? Was #4 lower than the others?

I've removed the cable only from the transmission end. There was a frayed wire in the center of the cable. You'll have to turn the cable while pushing on it to get it to line up with the speedometer connection.

Possibly but it could also be a frayed cable that catches on the inside of the sheath when it flexes. I'd remove the sheath and inner cable from the car. pull the cable, clean everything, lube, and reassemble if there's no damage.

My 71 speedo was always steady. I'd check the speedo cable and sheath for defects. The flexing of the sheath when going over bumps may be related.

Brain fade. I've spent the last week working on my brother's 31 Model A Hot Rod with a 350 Chevy in it.

How long does it idle before fouling a plug? Assuming (correct me if I'm wrong) it starts to run on seven cylinders, will the plug clean up if you run the engine at high revs (Italian tune-up) for a while?

I don't know where the oil is coming from but like C.O. I don't think it's coming from the carb reservoir. Ztherapy has an excellent video on SU carbs. It describes their function in detail and has many tests to ensure the carbs are working properly. With that thought in mind, you might give Steve at Ztherapy a call and ask him about the oil problem.

The studs in the pics don't look like they're parallel with each other nor does one of the studs look like it's installed 90 degrees to the hub. I agree with Charles, put a nut on the offending studs and tap them.

With the engine off, lift both carb pistons to the top. There should be considerable resistance in both. Then let them drop. They should drop at close to the same speed and hit the carb bridge with an audible clunk.

How often do you have to add oil to the carbs?

Tank venting is a possible cause. Do you know if it's running rich or lean when it's acting up? I always checked mixture problems with the choke first. Ease it on during the problem. If the problem improves or goes away, it is running lean.

Can we all agree it was a very loose North American term that implied nothing more than a hatch vent move? Nothing will be gained by making a mountain out of a molehill.

Perhaps we could all agree to disagree on the subject of the Z series question. Knowing that there were improvements throughout the model years I will continue to describe the difference between Series I and II 240 Z as the hatch vents move to the C-pillars. I believe that was all it was meant to describe (in the USA) originally.

By now, we all know Nissan never had a series I and II 240 Z in America. However, it is a description that works (in America) for determining if it is an early or late model 240. Just to stir the fire a bit more the description also works for 260s and 280s due to the mid-year changes, but only in America as far as I know.

Perhaps a mod to richen the mixture during acceleration? I would think a heavier spring would do the same thing.

If the problem started with a new pump I'd run a fuel pump pressure and volume test. Last year there was quite a bit of discussion about new mechanical pumps not working properly.

Over 20 years of daily driving my 71 (mechanical pump), I never once saw my firewall-mounted filter anywhere near full. It drove me nuts for a few years but I never had any fuel starvation problems with a half-full filter, so I gave up worrying about it. Describe the stalling issue.

It appears that a company called Buc-ees in and around Angleton, Texas sells ethanol-free fuel. A bit of a drive but I'd do it.