ninjazombiemaster

Change your spark plugs?

Dammit Newman...

Will do! The cap came from Rob over in Canada the other day and looks great. Can't wait to get this thing restored..

Okay, I get it guys! ;D - Buy Ztherapy Haha. I'll watch the video and learn 'er up. Thanks everyone. EDIT: Oh - forgot to mention - Today the engine seems to have started Loping - looping, whats the word? Its Idle RPMs are wavering all over, and it seems to do it in drive as well, less noticeably at higher speeds. When moving, it kind of feels like someone is lightly tapping on and off the brake pedal consistently. When that happens all the sudden, its an indication of a vacuum leak, no?

Thanks E, I'll take a closer look at their stuff. Blue, I'm honestly not sure on most of those questions. I've been reluctant to dig that deep into the carbs.. But I'll inspect each of those things and report. Thanks. As for the plugs, they were a little brown on the tips, but looked practically new, that aside. The #1 cyl plug was a little blacker, but it was the only one, and not significantly.

I've tripled checked the vacuum advance and it seems fine from testing - not to say that there isn't something causing it to stick when driving that isn't being observed when I check it. As for Z therapy, I've looked at the site, and I'm not real sure where to start. I'm new to carbs as far having a carb'd daily driver, but I do know a thing or two, and spent much of my childhood at my dads auto shop. I'm by no means an expert or even real experienced, just a beginner with a head start.

This is a continuation of my other thread, but the problem the OP was about has been resolved, I figured it was time to start fresh. Since the weather has gotten cold, my problem has gotten worse, as they usually do. Basically, the issue is that my cold starts are real rough, pumping the gas like crazy and cranking. Once it starts, it backfires. While its cold, it usually kills the engine but a few starts gets it to a healthier idle. Eventually it gets to where its idling decent, so I get the car moving. It does okay from here on - but it backfires and stalls for several minutes, which is scary as hell in traffic. Once it warms up the backfiring stops, but not all is well. It seems like my low end has a lot of power - like, a lot of rubber burning, tire screeching power. This is the 1,000-2,500 RPM range. But as soon as she revs to 3,000rpm the fun stops - and there's no power gain. I'm not real familiar with the power curve of these cars, but I seem to recall them showing a steady gain until 4,500-5,000rpms. Mine seems to peak at 2,500rpm and then fall flat on its face. Getting to high speeds its rough. 0-60 times are twice what they should be, and once it gets there, going faster is no easy task. When I bought it, it did not seem to perform this way... Its a '73 240z, but has a round top conversion. Up until a few days ago, it had a Pertronix Ignitor, but broke and was just changed back to points, so that and the condenser are new. The problem existed with the Pertronix as well. The timing is currently set to 12, and the dwell is at 40. It idles around 8-900 on a nice day at operating temperature. The backfiring is not present if I advance the base timing, but the flatlining performance remains. Spark plugs look good and fresh and compression is strong and even, and the vacuum advance seems to do well too. I been able to identify any issues with the dizzy so far. I installed a new fuel filter a few tanks ago, and its still clean and full, so I don't really suspect problems with the fuel itself, but the fuel pump isn't out of the question, but it doesn't seem to be the main issue. The fact that advancing the timing fixes the backfire makes me thing that something is forcing the timing to retard, especially when cold, causing it to backfire. As for the performance, I'm not real sure... Valves out of adjustment, timing not advancing far enough, vacuum leak, something else? I know that was a novel, but if you guys have any suggestions I'd greatly appreciate it. If you need any more info, let me know.

Not huge, but they aren't a large cost either, and the Thunders halved the overall resistance, which has got to have a role on the overall engine dynamics, even if its subtle.. Out of curistoty, Zedyone, why didnt you like the thunders?

Performance definitely matters, but it drives me crazy that my NGK wires are blue.. I had no idea the resistance was so high, relatively speaking.. I wouldn't mind taking either the black Thundervolt or Red Taylors off your hands?

I was gonna see if I couldn't do something like Cap'n Obvious did, with a threaded insert of some kind. Indeed, haha

Okay.. Well two nights ago she broke down. The rotor sliced the wires in the distributor and tore them from their sockets, so I couldn't solder it back together. Turns out it was equipped with a Pertronix Ignitor - Don't know how I missed that. Regardless, a $60 a tow and a few bucks in parts later shes running again. Ive got my Dwell at 40 and my timing at 12. That should be fine, right? Anyway, its still backfiring and stalling and hard to start cold - Once its hot, the only problem is it loses tons of power at exactly 3000rpms. Anyone know the power curve on these cars? I thought it was more in the 4-5k range. Mine seems to haul arse in 1,000-2,500 and then just flop. I'll give the valves another look over, any other thoughts?

I got it off, just by doing it a little a day at a time. Took about a week altogether. When I got it off, it looks like its not threaded at all - Looks like that stuff was just glue, and I was making the threads as I turned. Haha. What a pain.. I've started sanding, and it looks better already. Still waiting for my gear map to arrive from Canada from Rob, then I'll rethread it. Thanks for the suggestions guys!

Looks grand! Cant wait to see it put together.

Looks great! I think your work paid off nicely on this. Cant wait to see it all put back together.

Jeez, its like it rolled off the lot and right into a time capsule.

They looked fantastic, actually. I double checked the vacuum advance and insured it was indeed working. I think something is causing the timing to drop by a factor of 12 degrees sporadically, and since the timing is now set to 10 instead of 22, it drops down -2 causing a backfire. If thats the case, the PO must have advanced it so that the when that happens, it drops to a healthy 10, and doesn't backfire or stall. I'm pretty new to this so, I could be totally off. But I think I'll have to take apart the distributor and see if something is catching it.

Guess so. I'll get around to it as soon as I can. It's tough to find time when its your daily driver, haha. Thanks.

Looks nice. And yeah, I wonder too about the stripping. The threads on the stick itself appear to be in good shape There must be some lock-tight on this thing. Maybe I need to add a belt wrench to the toolbox, not that my makeshift ones have really helped.

Okay, we've still got trouble. With the timing back at 10, it now seems to have started backfiring (as in the pop is from the front, vs after-fire) and stalling. I'm guessing the PO advanced the timing in order to half-arse fix another issue. I'll definitely take a close look at the distributor. Any other suggestions or ideas?

I had that exact though, I'll give it a shot.

That may be what happened, there appears to be some sort of resin or compound in the center of the knob when viewed from the top that could be glue, as the cap is missing. I've assumed its just a filler, but it could possibly be binding up. Its just strange that it'll move just an 1/8th turn every once in a while, I couldn't think of any sort of glue or locking mechanism that would allow it to turn a small amount once a day, haha. I'll also try heating it up when I get the change.

I could be wrong, but it doesn't seem like there's clearence for a nut. I'll get a flashlight and take a good look though. I'm pretty sure it's stock, or at least OEM. I think I may have a spare shifter somewhere, if I don't have luck finding a lockin mechanism, I'll just remove the whole thing. Thanks for the suggestions.

Should've been more specific, it won't turn. It's taken me days to get it turned just a small bit. I even wrapped it in a rubber glove, which was then wrapped in leather and tried turning it with a wrench and it didnt budge.

Just a Z. I'm pretty sure it hasn't been removed in somewhere between 7 and 39 years. But I'd lake to sand and refinish it, and put on a new cap. And try out my new one in the meantime. Maybe now it's dark and a little colder, the metal wil have contracted. Hah.

May not have helped get the knob off, but I got a good laugh. And sorry for these typos. Typing on an iPod... Any suggestions on getting that thing removed?