I got some questions on a recently purchased Z

[DrifterXRPS13]

The car in question is a 72 240Z...the previous owner said he restored it about 10 years ago, he painted from green to orange and did some engine work and then put it in storage...we did some work to it and now it runs but it won't turn off, you have to disconnect the battery to turn it off, my other question is it's got a 5 speed, i was reading the z timeline thread and it said the 5 speeds didn't come until 77, how can i tell what trans and what engine this thing has...i can't seem to locate any numbers or codes...does anybody know what the problem might be and if this trans is from a newer model and maybe it's causing issues...idk, new to the Z thing, a little help would be appreciated, thanks guys

[reggiegsd]

What an odd symptom. If the ignition switch will not shut the engine off but lifting a battery lead will, then something is badly miss-wired.

One of the biggest advantages of an early Z is the incredible interchange of parts between 1970 and 1983. Unfortunately, that is also one of the disadvantages. You can swap the drivetrain from an '83 into a '71, including the fuel injection if you wire it properly. You can mix and match heads and blocks from different years to get different compression ratios. Transmissions from different years will swap with a little effort. Basically, what I am asking is what is in your car?

Unlike your 240SX where you just waive your credit card and go fast bits show up FedEx, with a Z car you need to be able to identify the individual parts and what parts will work with what.

What block do you have? The number is molded in down by the motor mount.What head do you have? The number is molded in between plugs 1 and 2.What 5 speed? 280Z? 280ZX? 2000? pickup truck?What intake? Early SUs? Late SUs? Hitachis? L-Jetronic? Or one of about 5 different after market setups?Even if you have the original engine you could have one of several diferent distributors. Which do you have.

Any combination of the above could lead to the symptoms you describe.

Does you battery die when the car sits?Will the engine continue to run with the ignition key on and a battery lead lifted.Did you get a later internally regulated alternator and leave the external voltage regulator in the circuit.Do you have any aftermarket ignition bits?

I'm not trying to be a jerk, but welcome to the world of old car troubleshooting.

Reggiegsd

[evildky]

the run on issue is most likely the result of an alternator upgrade, either the voltage regulator is fried, or the alternator is incompatible, when the alternator is upgraded to an internally regulated unit you need to put a diode between 2 of the contacts, here is an article covering the swap compliments of zhome.comhttp://www.zhome.com/Care/Altwire.htm

[DrifterXRPS13]

Thanks for all the info guys, i'm gonna check what block, head, and intake/carb setup i have when i get home from work...how would i identify the trans?

I'l also check on that alternator, in fact i'll get some pics up so maybe you guys can take alook see.

[DrifterXRPS13]

This is what i've come up with

1. Block is L242. Head E883. 5-spd unknown due to me not knowing how to identify it4. I'm assuming that when you say intake you mean the manifolds, in that case they are E88 as well, sorry, i don't really know the differences of SU's or any of those other ones you mentioned...5. Distributor is stock

1. The battery does not die when the car sits2. The engine will not continue to run with the ignition key on and battery lead lifted3. Alternator looks stock as well4. There are no aftermarket ignition items.

Removed the Voltage regulator to test it with the battery while the car was running, it made the volts rise and overcharge the battery...it looks a bit corroded on the inside but still functioning, if you tap it makes the volts rise and fall...could this mean it's a bad regulator?

[evildky]

the block and ead are correct for a 72, as for the 5 speed it's kinda tricky to identify

the carbs, assuming they are a side draft, they either have flat tops, or the sides are rounded over, the round top units are heavily favored, if they are downdrafts (which is a popular mod on cars that came with the flat tops) then they would be webber DGV's

stock distributor=points, which suck, I highly recomend upgrading to a petronix or later electronic unit

the run on issue could also be a crossed wire or 2 in the dash, behind the stereo where the fuse panel leads connect to the main harness there are several other connections, and many of them look them same, not lake modern cars that can only go together one way, you might have to get a diagram and track each wire or group of wires, lets hope it's an alt issue, I don't think the alt should be excited with the regulator off so it might be a bad alt, in which case it's a good idea to upgrade to internal regulated ZX style

[reggiegsd]

Ahh... Key information.

"2. The engine will not continue to run with the ignition key on and battery lead lifted"

The engine is running off of the battery or a very weak alternator.

This can be due to: A dead or weak alternator (not common), A botched alternator swap (How many wires are attached to the back of your alternator?) A bad voltage regulator (possible but also not common), A bad fusible link (very common), Corroded connectors (guaranteed they are there whether they cause this problem or not).

When you factor this problem in with the original symptom, a botched or corroded wiring job is most likely.

Whenever you buy an old Zcar, immediately do the following:Replace the spark plugs with NGKs.Open up and clean ALL of the electrical connectors in the engine bay. Especially the fusible links.New belts and NEW RADIATOR CAP.Oil in the carbs.

[vqpwrd240]

Thanks for the help so far guys. This is my car and my brother had posted on my behalf.

Well the car was running and it is not anymore. I know that the voltage regulator is not working because it constantly charging the battery. It causes the battery to over heat and start to leak. It is also causing the wire that running to the fuse block to get extremely hot. I talked to a friend that is a nissan master tech and he said to check the wiring to and from the ignition to the coil. That may be giving the constant power to the key in the off position. But I really do not know how to check that. I am not that good with wiring especially since I am not familiar with Z wiring.

I have a regulator on the way. I just need to figure out how to get it started again. Thanks in advance for the help.

Ferhan

[evildky]

what's not working when you try to start? is the engine turing? got spark?

[vqpwrd240]

The engine is cranking over. I can smell the fuel. I did not check the spark but I know that the contacts are opening and closing in the distributer since I had to adjust them. It was running before and should still have spark.

Ferhan

[evildky]

has it run since you adjusted your points? what gap did you set?

[reggiegsd]

POINTS?

Use your timing light to check for spark.

Get a distributor from a ZX. Its a direct bolt in and has the control module mounted to its side. And best of all, NO POINTS.

If you insist on points (Why?), use either Datsun Z points or Bluestreak points. Most others are designed for other L-series engines and will bounce before you reach 7000 rpm. Bad news for performance.

[vqpwrd240]

Points are set between .4 and .5 mm like the manual said. They originally won't even open when I installed them. I just got home so I will doulbe check.

Ferhan

[vqpwrd240]

What year zx is a direct bolt in? I may look into it. Thanks.

Ferhan

[vqpwrd240]

First the good news. I finally got it to start. I had to close the gap on the points a good amount to get to fire. It starts right up now. Thanks guys.

Now the bad news. I will be replacing the voltage regulator once it arrives. I noticed a new symptom today after it started. The positive white wire off the starter was smoking while the car was running. I am thinking that I will replace it with an 8 or 4 gauge wire. Is the voltage regulator causing this or is there an other germlin to hunt down?

Ferhan

[evildky]

ny of the electronic distributors 75-83 except the optical turbo's will bolt in, you jst gott aire them up, the 79-83 n/a with the replacable module on the side seems to be favored, I ran the VR style from a 78 as I had one from a parts car, I've heard nothing but good things abut the petronx conversion so it's certainly worth consideration, as for your meltdown, I'd start pulling fuses, you only need one to run IIRC, then you can start putting fuses back till you find the circuit causing the issue, I've personally had issues due to wiper motor and the hron, I also stopped having these problems when I upgraded to the z car creations internally regulated unit, now my car has working wipers again, I can't explain it but it works now

[vqpwrd240]

I will play around with the fuses today. Sorry to sound stupid but what is IIRC? Also, what internally regulated unit are you talking about?

It seems like the last owner removed the fuel filter. Anyone have pictures or a diagram showing the correct routing for the filter? I have a new one to put in.

I would be very greatful if some could call me as well to talk over some of the issues I am having with the car. I can be reached at 847-220-3841.

Ferhan

[DrifterXRPS13]

IIRC= If i recall correctly, or if i remember correctly....freakin noob!

[evildky]

lol, yup, handy acronym as my memory fades

the 79-83 280ZX uesd an internally regulated alternator, ti bolts in but requires the diode mod, Z car creations used to sell a bolt in 1 wire which is what I am running in my 71the fuel is quite simple, the feed line comes up from the frame rail into the filter out to the feed line for the fuel rail, then the outlet hooks to the return line, pretty simple

[vqpwrd240]

I blew 2 of the 10 amp fuses today. They were the lowerest in the fuse box right next to each other. My regulator did not come in today so it should be here Friday. Once I replace the V.R. I will take it to my friend to see if he can figure out the staying running issue.

Ferhan

[reggiegsd]

How many wires are on the back of your alternator? There should be three.

[vqpwrd240]

It is original and I think it has 3 wires. I can double check.

Ferhan

[vqpwrd240]

Alternator has 2 wire and a plug in the back.

I replaced the voltage regulator and the voltage at the battery with the car running is 18.4 and holding. I would assume that that is what it should be doing.

The white wire off the starter is still getting very hot and smoking. The white with red strip wire going to the fuse box is also getting pretty hot.

So should I be looking into re-running both of those wires? Thanks.

Ferhan

[evildky]

you're voltage output should never exceede 14.4 volts, you're alternator should also have a ground wire on it, if any of the wires are getting hot you have a problem, with the battery disconnected check the resistance to ground on that whait/red wire, it should be wide opne, I'm willing to wager you have something shorting somewhere, just start unplugging things til it's open

[vqpwrd240]

Here is a link that has the same alternator that I have. It is hooked up the same way. Is the E the ground wire?

http://forums.hybridz.org/show...rsion

Where should I start pulling plugs? Thanks.

Ferhan

[vqpwrd240]

Here are a few pictures.



This is when I got it to work right for a bit.

I took your advise and pluged the fuse for the wipers (20 amp). Checked the voltage before starting the car and is was at 12.54, checked it after starting the car and it stay right there. I let the car run for 10 to 15 minutes and it did not increase. I shut it off. Tried to start it a few minutes later and I got nothing. It would not crank, no power to lights or anything. A few more key turns but nothing. Double checked a few wires and hit the starter a little. Turn the key and it started up. Checked the voltage again and it had shot to 17.32. The fuse is still pulled. Now what the hell happened? Can someone call me and walk me through a test or two? 847-220-3841. Thanks.

Ferhan

Modified by vqpwrd240 at 7:32 PM 5/24/2008
Modified by vqpwrd240 at 7:35 PM 5/24/2008

[evildky]

ugh, these things can be a nightmare, I strongly recomend switching to an internaly regulated unit, then check each circuit's resistance to ground, if your fuse panle is damaged at all I'd also recomend switching to the new blade type replacement box, the wiring on these things is backwards by todays standards, no easy answers, mine is sort sorted only where needed, I got one bud that pulled the entire harness from the car and unwrapped and rewrapped the entire harness to find his problem, which turned out to be a couple of severly corroded and shorted wires, another bud bought an aftermarket fuse panel and a bunch of wire and made his own replacment harness

[vqpwrd240]

Well, I am thinking about getting a EZ wiring kit or painless kit.

If a run a internal regulated alternator, would I still need to use the voltage regulator?

Ferhan

[evildky]

nope, one of the big benefits to going internal is one less thing hanign in your engine bay, if you decide to rewire here is a thread from hybrid that should clear a few things uphttp://forums.hybridz.org/showthread.php?t=94822

[vqpwrd240]

Thanks. I will also unplug the V.R. to see if that does anything about the continuous charging.

Evildky, would you be willing to help me if I decide to rewire the car?

Ferhan