MariaAZ

I disconnected the vacuum line and plugged it at the manifold and the car runs fine. It brakes fine as well (takes more effort but Hubby, who drives it, says it's not really bad) so we've got a bit of time. Could it be a faulty check valve? I read a reference in one manual that the check valve may cause hard braking problems.

Thanks for the input. I borrowed a car for today and have a couple days to figure out what to do. I've got another Z I can pull the booster out of until I can get another one, and I've got a few manuals to help. From the experienced voices, how difficult would you say the remove/replace process is? I've done a bit of wrenching under the hood, but never anything with brakes beyond replacing the master cylinder on one of my Roadsters.

We just had a problem develop with our '74 260Z. When the brake pedal is depressed, the engine revs. The brake pedal is also very hard and it takes a lot of strength to push down. Any thoughts/solutions would be greatly appreciated, as this is currently our only running vehicle.

I hope I'm not stepping out of line with a story about our '63 Datsun Roadster (it IS related to the Z after all). We were on a Sunday drive in the Roadster and passed a Nissan dealership. The 350Z had just come out and they had quite a selection, so we decided to stop by. After a few minutes looking at the Zs, I glanced towards our Roadster and saw a small crowd of people standing around it, with a very impressive-sounding Nissan sales guy talking quite authoritatively about "the MG." I walked over and very nicely said "actually, this happens to be a Datsun Fairlady" to which he attempted to correct me with the "fact" that Datsun didn't import any cars to the US prior to the early Z cars. I asked him to look at the badge on the center of the steering wheel, he said quite unimpressed "it's a P". I straightened the steering wheel and asked him to look again, but he wasn't buying that it was actually a lower case d. There was only one thing left to do; I popped the hood, pointed to the VIN plate and asked him to read it. He stood there for a moment, muttered something about having to get back to work and wandered off. However, I quickly discovered that opening the hood of a 40+ year old Datsun practically in front of the repair bays of a Nissan dealership is a good way of attracting mechanics. Several came trotting over and spent a few minutes studying the engine bay. I started getting a bit concerned that we were attracting unwanted attention, as a guy came out of the sales office and watched us with a not-too-happy look, so we beat a hasty retreat.

Gary, unfortunately we have to test anything built from '67 up. I'll have to find exactly what they test, it's two elements; one is CO and I believe the other is hydrocarbon, both at idle and at load. My 260Z has a stock engine, running home-rebuilt SUs (about 6 years ago) and no emissions. It's passed for several years, last year was the first it failed. The 240Z original engine has been rebuilt and overbored, has professionally rebuilt SUs (about 3 years ago) and also no emissions. This is the one that fails every year, and each year it's a little worse. I don't know if the county is tightening the requirements (entirely possible) or if it is a function of wear of the carbs. I'm wondering if the needles could be causing the problem? I assume they DO wear.

No help with question #2, but as for question #1, my experience is yes.

OK, that doesn't sound bad Not exactly good, but I could definitely handle that.

Thank you!

Hubby's 240Z is at the mechanic's. He drove it to work and it ran like a top. When he tried driving home, the engine died and when he started it, it ran rough. Sparks were coming from the muffler as well as black smoke so he limped it around the block and back to the parking lot. The muffler was incredibly hot and an odd burning smell (not like oil though) filled the car. When I got to the lot to pick him up, he started the car up. It sounded fine to me but Hubby said it wasn't running right and that odd smell started in the car again, but I couldn't smell it outside. No smoke from the tail pipe either. We had a cat converter installed a couple months ago as a last-ditch effort to get the car to pass emissions. Any idea what the problem is?

I have a water leak on one of the hoses that comes out of a tube off the thermostat housing. There are three hoses on this tube; one comes straight out and goes to a line around the back of the engine (possibly to the heater?), and two come out the bottom of the pipe and appear to go into the intake manifold (it's hard to tell, I haven't pulled the hoses off yet to trace where they go.) Also, the hose that goes straight in looks like it's been blocked. When I pulled off the hose I found what looks to be a bolt screwed into the pipe then cut off. I couldn't find reference to these hoses in neither my Clymers nor my Haynes manuals and was wondering what they are. Below is a picture, the part in question is the rusty discolored tube in center.

Pardon me for this total newbie way of describing this... Our 240Z's horn doesn't work. When I removed the headlight switch to clean the contacts, I noticed that the combo switch/turn signal part had a broken plastic tab on the bottom. I had pulled the switches off my 260Z earlier and recognized the broken piece as being what looked like a mounting bracket for a curved piece of metal that appears to be a contact point for the horn, and a loose red wire with a taped up end. I looked in my Haynes manual and couldn't find a diagram showing what it might be. Is this broken bit a piece of the horn? If so, can be replaced, or do I have to replace the whole switch? I know the horn works as there is a button under the dash that activates the horn, though I haven't checked yet to see if it's directly wired to the horn or patched in through the harness.

I thought I'd resurrect this thread as I have another question concerning removing the smog pump. Where can I find a cap to plug the fitting where the smog pump hose enters the manifold?

I've been reading that the gas shocks tend to raise the ride rather significantly. If I read correctly, this is most noticeable with stock springs. At this point I'll be picking up shocks from the local Checkers/Kragen or NAPA, all they sell are Monroes and KYBs. For the world of me I can't find the post where the height (at the rail I believe) was given. Both Zs have different symptoms; my 260 skitters about the road, and Hubby's 240 just is plain ol' rough. Would these symptoms indicate different suspension problems?

Good questions, DeMoore. I've been looking through my Haynes and Clymer manuals for that information. At this point in time, I want to bring my 260Z to pretty much factory specs. I'm not really worried about ride height or anything fancy. Hubby's '73 240Z might be a different story. In the future we'd probably want to put something a little fancier on his Z, as it's had a fair amount of mods done. A PO had installed sway bars and headers (and probably other mods that I'm not aware of) in an attempt to make a street racer. The head gasket was blown and one of the cylinders was badly scratched, so we opted to have the engine overbored (.030 I think) during a rebuild about 6000 miles ago. For the present though, I just want to correct the rough ride, and if I can get away with just the shocks I don't have a problem going back in at a later date and replacing the springs.

Thanks for the input! It doesn't really look difficult at all, I just KNOW I'll be suffering "while I'm at it"-itis though ETA; see, I'm already thinking "while I'm at it"; if I remove the springs and struts (I'm thinking "while I'm at it" I might replace the springs as well), what other parts would it make sense for me to replace at that stage?