Livin' Z Life - Historical Archive

[Arne]

28 Nov 2005 - More Alternator and Carbs

This past Thursday was a holiday here in the USA, so amid all the family, feasting and travel there was only limited time for playing with my car. But I did find time to install the alternator jumpers (with diode) and do some quick and dirty carb adjustments.

I had picked up the diode and built the jumper wires (one with diode, one without) earlier in the week, but didn't want to connect them until the weekend when I would have some daylight so that I could see the colors of the wires. So on Thursday morning I installed the jumpers. I would have to start the car to test them, but decided I couldn't do it right then as I had disconnected the choke cables in preparation for shortening them. I didn't have time to shorten them right then, and didn't want to mess with reconnecting them for such a short test. It would have to wait until later.

But on Sunday afternoon, I did have some time, and so I started by shortening the choke cables. After finishing that, I checked the float levels. The rear carb was about where it should be, but the front carb's level was 2-3 mm too low. After readjusting that, I turned both mixture adjusters all the way in, and then backed both out by 2.5 full turns as a starting point. I also remembered that since the injection has been removed, the ignition module I am still using (for now) retards the ignition by about 8 degrees if the injection isn't connected, so I advanced that by eye before attempting to start it.

Starting it was still a bit of a struggle, as my "baseline" setting of 2.5 turns was apparently too rich. It took a bit of fiddling to get it close enough that it would run without me babying the throttle, but once it would idle on its own, it didn't take too long to get it running decently.

So now the carbs are set fairly close. When warm, it starts almost instantly, idles fairly well at about 800 RPM, no longer misses at all, and has good throttle response. I'm certain that they could be fine tuned a bit, but they are plenty close enough for now, considering that there is lots of other work to be done before it will be ready to drive.

As for the alternator and its diode, the results are all good. The ammeter shows a good charge, and the engine now shuts off with the key as it should. And the tachometer works as well, and seems to be reasonably accurate. No remaining issues there, time to move on to other things.

 

Edited July 14, 2020 by Arne

[Arne]

3 Dec 2005 - Not Much News

Not much Z news this week. Got and installed a new air filter element, but that's not really notable. (Oh well, I noted it here anyway.) Also finished replacing and installing a few more of the various vacuum and vent hoses on the carbs and air cleaner assembly. That's about it for actual work on the car.

Started it again today, first time for a cold start since I got the carbs adjusted. Started from cold fairly easily, and runs very nicely when fully warm, but the in between is less than stellar. If I leave it choked, it runs rich and starts loading up and fouling the plugs. If I shut off the choke it wants to die. Now I know why Datsun designed these cars with hand throttles - if only mine was so equipped!

I also prepared for future tasks. I have an oil pan gasket now, and ordered a oil pump gasket today to go with it. Once the pump gasket arrives, I can proceed with replacing the leaking pan gasket and correcting the distributor drive shaft timing. Might get to that later this month, but might not.

Also ordered a rear outer hatch seal to keep rainwater out of the back end of the car. That will definitely get installed later this month.

[Arne]

11 Dec 2005 - Hatch Seal and Wiring

I don't know about you, but for me the holidays don't leave lots of time for playing with my cars. But this weekend did see a little work on the car, even so.

During the week, the outer hatch seal and oil pump gasket arrived. I didn't have time to tear into the oil pan and pump, but I did install the hatch seal. Since it appears to me that the outer seal is primarily there as a rain gutter, this should help to keep the inside of the car dry when it is outside and raining. I used the one-piece seal rather than the three-piece. I haven't confirmed which style is original to my car, but it doesn't matter to me either way. The one-piece is easier to get installed properly, so thats what I got.

So yesterday I removed the hatch, pulled off the remains of the old seal (which was a one-piece, by the way), cleaned the channel and glued the new seal down. It fit great, and seals nicely against the hatch when closed.

Today I spent some time trying to debug the wiring mess, and the findings aren't good. When the original fusebox melted for one of the previous owners, it took out one or more wires in one of the harnesses as well. Said wire(s) got hot enough to destroy the insulation on several other wires in the bundle as well. Several of the wires appear to be shorted together. This is where my problem with a constant battery draw comes from, I'm sure. The farther I unwrap, the worse it gets.

So I'm beginning to track down data on the various harness pieces, as I fully expect I'll have to replace some. Specifically the one(s) that connect to the fusebox leads with six-terminal connectors. There are several things I need to determine. For example - there are two separate medium sized wire bundles leading to the fusebox. As far back under the dash as I can see, they remain separate. Are these really separate harnesses? Or do they merge into one somewhere back in there?

I also need to determine how specific the different 240Z harnesses are. My car is an early '71, and since I'm not worried about absolute originality, will harnesses from a late '71 or a '72 be close enough that they can be made to work reasonably? For example, could I use a '72 harness if I use the later short pigtail fusebox?

And that's where I left it today, with lots of questions, and few answers. The project has gone extremely well up till now, with noticeable improvements without much in the way of money spent. I've got a feeling that's about to start changing...

[Arne]

18 Dec 2005 - Wiring Revelations

Did I accomplish anything you can see or touch this past weekend? No. But I did learn some things. I spent my time learning about 240Z wiring harnesses.

Like most cars of this vintage, Datsun built the wiring harnesses for the early Z cars in a number of connecting pieces. For the early 240Z there were "officially" three main pieces - engine, dash and rear sections. I say "officially" because it is more complex than that. For example, the dash section actually consists of two entirely separate harnesses, taped together into one "assembly." This two-part assembly was listed for replacement under one single part number. But each of those two sections also has its own part number, neither of which is the same as the single number of the replacement assembly. The number for the dash harness assembly is not on the harness, and the individual numbers are not listed anywhere in Nissan's parts catalog.

I found this out during my initial searching for replacements for my car's melted dash harness assembly. The individual part numbers on my pieces are 24013-E4705 and 06. These appear to translate to number 24013-E4703 for the assembled pair. The bad news? This assembly is no longer available new from Nissan (no surprise there), and might even be rather rare since it was only fitted to automatic-equipped 240Z's built from 10/70 through 12/70. Three months only.

Now I know why no one has tooled up to build replacement wiring harnesses for the 240Z. Apparently Nissan changed the harnesses not just every model year, but often every few months. In four years of 240Z production, there were at least six or seven major variations of wiring harnesses, for each transmission type. Call it ten different configurations, or thereabouts.

Worse, the dash harness assemblies are not the only ones that are specific to transmission type. The engine harnesses are different that way too. And no one can tell me for certain if you can or can not mix manual transmission dash harnesses with automatic engine harnesses. The general consensus though, is that you can not.

So it boils down to a pair of choices. I can try to find a good, intact (and possibly rare) dash harness assembly from an automatic car built between 10/70 and 12/70, or I can replace both the dash and engine assemblies with similar manual transmission harnesses from the same car. Any other option is uncertain - it may work, but it may not.

So I've got my feelers out for harnesses and/or parts. Stay tuned...

[Arne]

31 Dec 2005 - Back to Work

The holidays are winding down, but I've still got some time off so I had time to play with the car before the end of the year.

I started on Friday by draining the oil to replace the pan gasket. If you do it just right, you can get it done with the engine still in the car. This was to fix the oil leak that I had found while was working on the carbs. I also planned to drop the oil pump and reposition the distributor drive shaft while I was under there. This would allow me to finally be able set the timing correctly and still use the lock bolt.

So I pulled the drain plug, and with it came a bunch of RTV sealant and a thick paper washer! The copper sealing washer had been crushed so many times that it was paper thin itself, and so it no longer sealed. So rather than get a new copper washer for it (the one I picked up was 10 cents), whoever put the engine in my car tried to use paper and silicone sealer. That should have prepared me what what came next...

I started pulling the small bolts from around the pan, and quickly noticed that all four of the ones across the front of the engine were missing! Since the holes for those go all the way into the crankcase, my unknown benefactor had squirted RTV all over the front of the pan to attempt to seal it. After getting the pan off, I then proceeded to clean all the sealant off the engine and the pan itself. While cleaning, I noticed that one of the four "missing" pan bolts was actually broken, with the broken piece still in the timing cover. Whoever broke it appeared to make a few attempts to remove it, obviously without success.

While mulling over my options regarding the broken bolt, I pulled the oil pump and positioned the distributor drive correctly. As I suspected, it was one tooth off, which is quite easy to do. This task went just fine.

So I went back to cleaning while thinking about the broken bolt. And while doing so I found the OTHER problem someone "fixed" with silicone sealant. It seems that there is a small puncture hole in the bottom of the aluminum timing cover. Hard to say for sure how it got there, but since the hole is located right next to the broken oil pan bolt I suspect that the damage occurred during the failed attempts to remove the broken bolt. Like the other problems, a liberal coat of silicone was the solution of choice.

So. Another problem. I seem to find new ones faster than I fix the old ones. There's no reasonable way to get the broken bolt out of the timing cover while the engine is in the car, and now I find that the timing cover itself is bad as well. Time to make do for now, and worry about permanent fixes later. I replaced the oil pan with its new gasket, and three new bolts. One bolt is still missing of course, where the broken one is still plugging the hole. It should work better than before, however.

For the hole in the timing cover, I cleaned the area thoroughly and then applied a patch made of Permatex Liquid Metal. Since this part of the engine is not under pressure, I think this will work at least as well as the silicone did. This will buy me some time to decide how I want to proceed. I let the Liquid Metal cure overnight.

After I got oil back in it Saturday morning I set the timing and I drove it to the gas station to put a few gallons in the tank, and also to warm it thoroughly. I once again own a Uni-syn carb syncing tool (sold my last one after I sold the MG years ago), so I figured it was time to do the carbs right. So with the timing set correctly, I properly synchronized the carbs. Once that was done I spent some time fine-tuning the mixture. I think that I am now (finally) pretty much satisfied with the carbs and their mixture.

It still has a miss though, especially at idle. And it runs smoother the warmer it gets. So I decided to check the compression myself. I got 170-165-165-170-165-170, which is good for this engine (and is consistent with what I was told by the seller). After putting it back together and playing around with swapping plugs, wires and such, I believe that the problem is a weak spark which may be caused by the coil. When it is missing, it smoothes out at higher revs, and it does run much better when it gets good and warm. I used my inductive timing light to test the consistency of the spark, and found that when it is missing several cylinders don't have enough spark to flash the strobe. If you pull a plug wire and observe the spark, at idle it is small and inconsistent. Rev it, and the spark is much stronger. When warm (and running better) the spark is also much more consistent, even at idle. Coils can be rather temperature sensitive when they are going bad, so I think a replacement may be in order.

Final note for today, after running the engine a good while today, and even driving it around a bit, there is no fresh oil leaking at the front of the engine. So the new pan gasket and Liquid Metal seem to have cured the oil leak.

---

So the past few weeks have revealed a couple of fairly important issues that will need to be addressed before the car will be ready to drive. One is the wiring, the other is various engine problems.

Regarding the wiring, I now know all the original part numbers for the three major harness assemblies. I've considered several options, including sending various harness parts off to be professionally restored. But since my goal is not to build a show car, but just a very clean daily driver, I really feel that the restored harnesses are overkill for this car. So my plan at this time (subject to change, of course) is buy a matched set of three harness assemblies (ideally all from the same car), and then check each wire, clean every terminal, and repair and re-solder as necessary. That should give me the reliable electrical system that I need, at a much lower cost (other than eating a good chunk of my time). It also gives me the option to get harnesses from a manual transmission car, which are not required for the transmission swap (the auto harnesses will work just fine), but it does open up more possible donor cars.

As for the engine, it still seems to be relatively sound, but there are several items of concern. One is obviously the timing cover. It will either need to be replaced, or at least removed so that it can be repaired properly by welding. While it is out of the car, the broken bolt will need to be removed, if possible. But since that bolt may have broken because it was cross-threaded, a replacement timing cover may be the best bet. There is also another broken bolt, this one in the cylinder head. It is one of the exhaust manifold bolts, the one closest to the firewall. Like the one in the timing cover, it would be much more difficult to extract it while the engine (or at least the head) is in the car.

Considering all this, when I swap the transmissions later in the Spring (or Summer) I may pull the engine and transmission as a unit from under the hood. I had been considering pulling the transmission only from under the car, and leaving the engine in place. But pulling both may be easier in some ways, and it will give me an opportunity to evaluate and hopefully repair the engine at the same time.

The cooling system is also rather haphazard, and I'd like to overhaul it while the engine is out of the car as well. That will require a new radiator, all new hoses, new water pump, new thermostat housing, and probably a new fan and fan clutch to replace the aftermarket electric fan now on the car.

On the plus side, the engine does run pretty well when it's good and warm, has good oil pressure and compression, and makes no bad noises. The carbs seem to be good enough as is, although I'll probably want to replace the nozzle hoses and float bowl gaskets. If I do that, can get the ignition dealt with, and replace the timing cover, the engine should be fine.

So that's it for 2005. I've had the car for three full months so far, and there have definitely been some improvements. Of course, we still have a long way to go.

[Arne]

8 Jan 2006 - Ignition Update

Just a quick update this weekend, as I continue to prepare for the replacement of the wiring harnesses. Earlier today, I installed a new ignition coil and bracket. My hope was that this would finally be the item that cures the on-going engine misses I've been fighting. So during the week I picked up an inexpensive black coil and matching bracket, as specified for a '79-83 non-turbo 280ZX (since that's what my ignition is from).

Installation was very simple, took more time to open the packaging and gather the tools than it did to actually install it. And this time, I was rewarded! It started quickly and runs smoothly. No miss at all! The improvement was huge.

And that was it for the weekend, as the majority of my resources right now are devoted to the wiring. I'm slowly starting to search for the wiring harness sections that I need. That means that there may not be a lot happening with the car until the wiring is handled. But stay tuned anyway, I'll at least keep you updated as the hunt progresses.

[Arne]

16 Jan 2006 - Marking Time

So what happened to the Z this past week? Almost nothing. Some more research, hunting a few parts down, and a key.

For wiring harness, I found a supplier who is pretty sure that he has what I need. It might be a while before he can pull the parts, but since I don't really have any trains to catch here, that's OK. Most other suppliers of used Z parts have either told me that they don't have what I need, or have tried to sell me harnesses for a different year. I decided I'd rather wait for the correct parts.

I've spent a bit of time getting distracted too. Seems like every time I turn around there's some part on eBay or Craigslist that I will probably need before the car is done, but certainly don't need to have right now. I need to stay focused on one task at a time. (Well, maybe two tasks can happen concurrently.) The wiring is still job 1 for now.

So anyway, I really don't expect to get a lot done on the car until I get the wiring taken care of. Which will primarily consist of the replacement harnesses, a new fusebox and a lot of time.

I am still a bit bothered by the engine too. In the last update, I had reported that the new coil fixed the engine miss. Turns out that's not altogether true. It is much better, but cylinders two and five are still weak. When the engine is fully warm it's not very noticeable, but it is there. If I pull one of the offending plugs when it has been running for a short time (engine cold), the plugs are wet and smell of gas. If I pull one when it's fully warm and running better, the plug is dry but still black and sooty. A plug from one of the other cylinders has a tan color to the electrode. Reading plugs can be tricky, but this does seem to indicate that something is different in #2 and #5. I just haven't figured out what, yet.

Lastly, I had a little problem getting the door unlocked today, so I took the key code from the sticker inside the glovebox to a locksmith, and had them cut a new key from the code, not from the old worn key. Costs more to have done this way, but in this case my old key was so worn that I couldn't see wasting my money by having it copied. They had a hard time finding a blank, but once found they were able to cut a nice clean key. The new key works well in both doors and the hatch, but not the glovebox. The old worn key works in that lock, but not the new one. I don't know that I'll ever lock the glovebox, so I don't think I'll let that concern me for now.

[Arne]

22 Jan 2006 - Still Waiting...

Another week with not a lot to show. Still awaiting word on a wiring harness, the likely supplier for that part thinks he'll be able to confirm that he has what I need this coming week (if all goes well). I've done some additional hunting just in case, and have a couple possibilities in reserve. I've given some thought to picking up a parts car, too, should the opportunity arise. But I don't know where I'd put a second car...

I've also continued to slowly gather parts for later tasks of the project. Early next week I should receive a small batch of clutch parts as I begin to prepare for the transmission swap. I've also ordered a copy of the factory service manual, but it probably won't be shipped until the first of February.

Lastly, I also have a new set of front and rear springs reserved which should be ready for shipment soon. No, I won't be ready for these for a long time yet, but I felt this set was something I didn't want to miss out on. I got word last Fall about a limited run of new reproductions of the factory European Stage I springs that were a popular dealer option in the early seventies. These springs are slightly firmer to give better handling, but - unlike all the other performance springs available today - they will not significantly lower the ride height. So I reserved a set early to make certain I'd get some.

Oh yeah, remember I said the new key didn't work in the glovebox lock? I compared the new and old keys closely, and decided that there was a very small difference that I could fix with a small file. So the new key now works in all the locks.

That's all for this week, here's hoping that I'll have more to report next time.

[Arne]

29 Jan 2006 - ...And Waiting...

That's right, still nothing physical happening to the car. But the end of this lull is (perhaps) in sight. During this week just past things have started to come together.

That first small batch of parts for the transmission swap arrived. Not all of what I need, but some of the required new parts - slave cylinder, pilot bushing, etc. A second order of new parts is still in the future, as well as a batch of used stuff.

The factory service manual that I didn't expect until early February also arrived, much sooner than I had figured. So I can now easily find hints on how to do things, as well as find all the various specs and torque values (and wiring diagrams!!) I will need. I no longer have to wing it.

As for the wiring, I have located a good dash harness assembly and fusebox to go with it. These parts might be here and ready next week, but surely by the following week. Hopefully this will be all I need, but if not the engine compartment and body harnesses are available. Once in hand, I can begin cleaning, testing and repairing as necessary. Then I can plan the replacement of the bad parts.

And last week I mentioned the set of suspension springs I had reserved. Well, those also were shipped late this week. But when they get here, they'll just be checked over and put away for the future. The suspension will be one of the last mechanical areas to be refurbished.

So the next thing to happen will almost certainly be the removal of the dash for the wiring replacement. Probably not as soon as next weekend, but maybe later next month. I will continue to round up the remaining parts for the transmission swap, as I expect to do that as soon as I get the wiring sorted. Stay tuned!

[Arne]

5 Feb 2006 - Re-wiring Begins

I didn't know if I'd have anything to work on this weekend or not. But Saturday morning my replacement dash harness and fusebox arrived by FedEx Ground. They deliver on Saturdays? Who knew? Anyway, that was a good thing, as I didn't have much else planned for the weekend, other than watching the game.

I opened it quickly, and was immediately pleased by what I saw. The fusebox was solid and intact, and the harness looked good at first inspection. All the connectors were intact, and no wires appear to be melted. Pretty much just what I had hoped for.

So I straightened it all out, and began carefully looking at each terminal and connector. Comparing to my wiring diagrams, testing the wires, cleaning, etc. And I'm well pleased, it is a really good harness.

That was mostly yesterday. I had some time before the Super Bowl today that was not allocated to anything else, so I went out to look at pulling the dash out of the car. Well, it turns out that pulling the dash on an early 240Z is not all that difficult, and it is upstairs in the spare bedroom even now.

I haven't pulled the bad harness all the way out of the dash quite yet, still comparing and making sure all is right. The replacement harness is from a manual transmission car, which means that are no wires to connect to the kickdown switch, but I don't care, the transmission swap will be the next thing after the wiring. I've got all the gauges out too, and will clean them all up before I put it back together. No real surprises so far...

[Arne]

11 Feb 2006 - Reassembled

Well, I swapped the replacement harness into the dash during the week, and put it all back together today. And boy, putting the dash back in the car is a whole lot more difficult than getting it out! But after much laying on my back, half in the car, I got it all back together. It turns out that the only difference between the early automatic and manual transmission harnesses is the wiring for the kickdown switch. So there is now one unused wire on my engine compartment harness, and I have removed the kickdown switch from under the dash.

And how does it work? So far, so good. Everything that worked before still works. The clock even tried to go, but stops ticking after a very short while. I will test the rear defroster later. Still testing to see if there is a current draw pulling down the battery, but it doesn't look like it at this time. So far I'm happy.

On another front, Deanna and I drove to Corvallis (about 50 miles one way) on Tuesday to buy a spare engine. I saw an ad from a lady there who wanted to sell what she thought was a really low miles, complete 240Z engine. She was asking $200 for it. I talked to her on the phone about it, and she admitted that her boyfriend said it was low miles, but she couldn't confirm that. She thought it was complete, but couldn't answer my questions about it as she knew nothing about engines. She lowered the price to $100 while we talked, and so I figured that the timing cover and flywheel were probably worth that much, so anything else good would be gravy.

I found both more and less than I expected.

Yup, it was an 2.4 liter 240Z engine from a '72 or '73. But it is far from the complete engine I had thought she described. It's not much more than a long block, actually. But it does have the flywheel and timing cover I need. It's not even close to being a runner, it's been sitting in the weather and I can see (through the sparkplug holes) some rust in the bores. So the motor is definitely less than I had hoped it might be, but that didn't surprise me.

What did surprise me was when the lady told me about some other 240Z parts she found as well, that she would throw in with the engine if I wanted them. A miscellaneous bunch of engine and clutch parts for the most part, but also a pretty decent pair of tail lights, and a rear tailgate support strut that still has its gas charge!

So the spare engine is still in the trailer while I figure out what I'm going to do with it. The tailgate support is on the car now (no more broomstick!), and I'm going to clean up the taillights to find out what I really have soon. (The chrome trim on the lights isn't perfect, but is much better than what's on my car now.)

One last thought - on the way back with the engine, Deanna mentioned that this project seems to lack focus, when compared to other project cars I've had in the past. And she's right. I keep getting distracted by parts on eBay, or craigslist, or whatever. I need to stay on task, and not dilute my resources on getting stuff I won't need for months. ("Get thee behind me, eBay!")

So before I move to the next task, I will wait until I know I've got the wiring handled. When that is done, then I will proceed with the transmission swap.

[Arne]

12 Feb 2006 - Quick Update

Checked a couple of things briefly today. The first had to do with the wiring again, as I still worry that the dash harness may not be enough to fix all the car's electrical ills. But I have no evidence of that, all seems OK so far. For the first time since I got the car, I left the battery connected overnight, and the battery voltage did not drop at all. It still shows the same level of charge as it did yesterday. I will leave the battery hooked up this week, and re-test the voltage later. If it is still holding steady by next weekend, I can finally put this chapter to rest.

I also cleaned up the pair of taillights that came with the spare engine. They are also of the same 1973 vintage as the engine, and cleaned up pretty well.

The lights aren't as good close up as they look in the picture, but they are quite presentable, and much better overall than what I now have. As such, they will do fine for quite a while. The car is going to have to be pretty close to finished before I'm going to worry about finding any better ones, if then.