A few problems, 72 240z

[Tspite]

ok so ever since I put a new battery in my car the Cd player doesnt work, doesnt even turn on and my halogen/foglights dont work anymore either. In fact the old man I bought the car from had his battery cables backwards on the starter and hooked up black to positive and red to negative... But anyways I tested this with the new battery, put red on positive and black on negative and the starter started smoking but I took it off within a couple seconds. But ever since then the cd player doesnt work and the foglights dont either. I check the fuses under the center console and they all look fine. Im pretty clueless right now, any help would be appreciative.

The 2nd problem is there is a weird boom boom noise in the back where my suspension is, it makes the noise sometimes when i shift and sometimes when I go over creases in paved streets. The old man told me the noises I hear in the back is from the suspension "normally'. Said it was a Airglide suspension... I am still new to the Z's and any help I would be very grateful for. Im looking into getn her fixed up.. My dad tested both the front and back suspension and said they are in good shape. So I still dont know if its normal, my dad doesnt think it is but the shocks and suspension feel and ride really good other than the noise.

And when my z over heats she starts sputtering and turns off. I was told that I would want to rebuild the carburator, after pulln it apart with my dad it didnt look too pretty and it would squirt fuel out of the air horns, had to add 20 weight oil in thefloat bowls cause there were none in them and the carb was rigged up a little. But it does run better ever since we did the timing and added oil in the float bowls, but since it still acts up and needs a rebuild could this be the reason the engine overheats withn 30 mins and starts killing itself and sputtering, have to keep it revved up for it not to die but in some cased its still dies on me..

Sorry for the long thread but I really need some help from people who know more about these cars. Thank you very much in advance.

Edited April 14, 2011 by Tspite

[BoldUlysses]

"Airglide suspension" What in the world?

Is the "boom boom" an actual boom or more of a clunk? If it's more of a clunk, the u-joints on your driveshaft and/or axles might be shot.

The carb problems likely have little to do with the engine overheating. That could be a bad water pump, clogged radiator or hoses, or bad thermostat. At worst, you could have a blown head gasket. Are you losing any coolant?

As far as the carb tuning, have you looked over the technical articles related to how they work and tuning procedures?

http://www.classiczcars.com/forums/forumdisplay.php?140-SU-Carb-Technical-Articles

Good luck,

Matt

[Tspite]

Its more of a clunk yes.

And thats what I was thinking on the overheating thing but the carbs are def in need of a rebuild.

[IdahoKidd]

You obviously had the battery hooked up backwards (the PO had it correct). Hopefully the lights and the radio were fused. If not, they're toast. Black and red have are not definitive on multiple owner cars. You need to check to see that the wire going from the positive side of the battery hooks to the starter and the wire that goes from the negative side goes to the engine block (usually at a bolt holding the transmission to the engine) but a good solid ground. You should also find the wire that grounds the body to the engine. It is important to have it in place. Color of the wires is completely irrelavent at the moment. At some point, it is recommended you change out the cables to the correct color code. The clunk could be the diff mount and or mustache bar bushings, among other things. Put the car on jack stands, put it in first gear with the engine off, and firmly rotate the rear wheel while watching for movement in any part of the suspension or mounts. You may have to hold the other wheel from turning.

[Tspite]

You obviously had the battery hooked up backwards (the PO had it correct). Hopefully the lights and the radio were fused. If not, they're toast. Black and red have are not definitive on multiple owner cars. You need to check to see that the wire going from the positive side of the battery hooks to the starter and the wire that goes from the negative side goes to the engine block (usually at a bolt holding the transmission to the engine) but a good solid ground. You should also find the wire that grounds the body to the engine. It is important to have it in place. Color of the wires is completely irrelavent at the moment. At some point, it is recommended you change out the cables to the correct color code. The clunk could be the diff mount and or mustache bar bushings, among other things. Put the car on jack stands, put it in first gear with the engine off, and firmly rotate the rear wheel while watching for movement in any part of the suspension or mounts. You may have to hold the other wheel from turning.

What do you mean I had it hooked backwards? I bought the car with it like that and it ran fine (as far as electrical goes) I didnt mess with the battery until I bought a new battery cause this one was almost dead. Didnt flip flop any wires. i noticed the battery was hooked up wrong when I was taking the old battery out. Just sayin and making that clear

But I will prob get to that asap. Im gonna look at it tonight. Wont be driving it for another month(aside of test driving) Im thinking. Wel see i guess

[Tspite]

You obviously had the battery hooked up backwards (the PO had it correct). Hopefully the lights and the radio were fused. If not, they're toast. Black and red have are not definitive on multiple owner cars. You need to check to see that the wire going from the positive side of the battery hooks to the starter and the wire that goes from the negative side goes to the engine block (usually at a bolt holding the transmission to the engine) but a good solid ground. You should also find the wire that grounds the body to the engine. It is important to have it in place. Color of the wires is completely irrelavent at the moment. At some point, it is recommended you change out the cables to the correct color code. The clunk could be the diff mount and or mustache bar bushings, among other things. Put the car on jack stands, put it in first gear with the engine off, and firmly rotate the rear wheel while watching for movement in any part of the suspension or mounts. You may have to hold the other wheel from turning.

What do you mean I had it hooked backwards? I bought the car with it like that and it ran fine (as far as electrical goes) I didnt mess with the battery until I bought a new battery cause this one was almost dead. Didnt flip flop any wires. i noticed the battery was hooked up wrong when I was taking the old battery out. Just sayin and making that clear

But I will prob get to that asap. Im gonna look at it tonight. Wont be driving it for another month(aside of test driving) Im thinking. Wel see i guess

[Bruce Palmer]

Someone sold you a battery with the posts reversed then..... Pretty common mistake. Did they match up battery for battery or did they go to the book and come back with the battery it called for? PO might have had the wrong group battery in before and hooked up the cables according to that battery.

How'd that 20 wt. work out in the float bowls? Nyuck nyuck We sell a dvd that takes the mistery out of SUs for most folks.....

[IdahoKidd]

ok so ever since I put a new battery in my car the Cd player doesnt work, doesnt even turn on and my halogen/foglights dont work anymore either. In fact the old man I bought the car from had his battery cables backwards on the starter and hooked up black to positive and red to negative... But anyways I tested this with the new battery, put red on positive and black on negative and the starter started smoking but I took it off within a couple seconds. But ever since then the cd player doesnt work and the foglights dont either

You switched the cables and smoked the electrical system. You just stated that.

What do you mean I had it hooked backwards? I bought the car with it like that and it ran fine (as far as electrical goes) I didnt mess with the battery until I bought a new battery cause this one was almost dead. Didnt flip flop any wires. i noticed the battery was hooked up wrong when I was taking the old battery

And why oh why would you buy a new battery because the old one was almost dead? Seems pretty clear you are in way over your head.

[Tspite]

ok so ever since I put a new battery in my car the Cd player doesnt work, doesnt even turn on and my halogen/foglights dont work anymore either. In fact the old man I bought the car from had his battery cables backwards on the starter and hooked up black to positive and red to negative... But anyways I tested this with the new battery, put red on positive and black on negative and the starter started smoking but I took it off within a couple seconds. But ever since then the cd player doesnt work and the foglights dont either

You switched the cables and smoked the electrical system. You just stated that.

What do you mean I had it hooked backwards? I bought the car with it like that and it ran fine (as far as electrical goes) I didnt mess with the battery until I bought a new battery cause this one was almost dead. Didnt flip flop any wires. i noticed the battery was hooked up wrong when I was taking the old battery

And why oh why would you buy a new battery because the old one was almost dead? Seems pretty clear you are in way over your head.

Ya I tested to see for sure, ya it was stupid to do. The old battery NEEDED replacing anyways tho. Wouldnt keep charge anymore after the first time it was jumped to drive to my place.

If you aint got anything positive to say then dont even post/reply. Im trying to solve the problem, and work on it as I go. Not be immature on a message forum. Js

[Tspite]

I went to and made sure and I bought the proper battery for this car, I got an old repair manual as well with the car. And I do need to look into the dvd. how much does he want for 1?

The 20 wt and the ignition timing adjustment made the car run alot better but the carb likes to start messn up when the engine overheats..

[Tspite]

Someone sold you a battery with the posts reversed then..... Pretty common mistake. Did they match up battery for battery or did they go to the book and come back with the battery it called for? PO might have had the wrong group battery in before and hooked up the cables according to that battery.

How'd that 20 wt. work out in the float bowls? Nyuck nyuck We sell a dvd that takes the mistery out of SUs for most folks.....

I went to and made sure and I bought the proper battery for this car, I got an old repair manual as well with the car. And I do need to look into the dvd. how much does he want for 1?

The 20 wt and the ignition timing adjustment made the car run alot better but the carb likes to start messn up when the engine overheats..

[IdahoKidd]

Pointless