Med Center Z Posted July 18, 2012 Share Posted July 18, 2012 Lets make this short an easy issue 1: I picked up a other 240z, this one is a 73' (picked up the 71' last week) Since i gotten the 71 to turn over and idle well i wanted to do the same with the 73' but since i put the battery in (on the stock oem terminals) the car is just making a click sound when you go to start it. On the first try of turning the key to start it, it spun the the motor for 2 seconds, then stopped (i was holding the key to start mod this entire time). Ive never used a AMP meter gauge (oem gauge) but its reading - when you try to start it. I thought it may be the starter and cables and for 100.00 total i new i would replace them anyways so i did so hoping to fix the issue, but sadly no luck. I clean or replaced all the wiring to the start as needed. Now this is why i think i have a dead short. issue 2: On the eom terminal there are 2 wires bonded to the terminal internally(we are talking about the positive terminal). I cut these 2 wires and striped the rubber a bit to get a good lead to use for the new red colored positive terminal i got to replace the old oem terminal. Now i noticed that one of the 2 terminals is from the starter to the Positive terminal and the other (the smaller wire of the 2) is coming from the firewall. when i connected these 2 wires together the battery started to arc (only for 2 seconds/pulled the terminal away). without this wire from the firewall(the smaller wire of the 2) connected to the positive terminal there is no arcing and sparks flying. my question is, is this wire from the firewall a ground? or is there a dead short in the firewall wire? its odd, because the oem terminal had these 2 wires running internally on the same terminal, so was there a divider of sorts or a ground internally? i hope i don't have to pull the dash or a/c unit (scroll box) because my a/c is blowing ice cold after all these years. i looked through my manuuals an have read around but not much to find on this wire coming from the firewall. Quote Link to comment Share on other sites More sharing options...
Miles Posted July 18, 2012 Share Posted July 18, 2012 Did you check the battery voltage? Autozone etc can check the battery and alternator for free. Suggestion: use pictures instead of words to describe your wiring issues. Use words to clearify the pictures. Quote Link to comment Share on other sites More sharing options...
NewZed Posted July 18, 2012 Share Posted July 18, 2012 (edited) Use an ohm-meter to test if a wire is grounded before connecting it to the positive terminal of the battery. If it is, do not connect it to positive. Sparks are bad. Edited July 18, 2012 by NewZed Quote Link to comment Share on other sites More sharing options...
cgsheen Posted July 18, 2012 Share Posted July 18, 2012 Sorry the A/C tubing is in the way... Quote Link to comment Share on other sites More sharing options...
beermanpete Posted July 18, 2012 Share Posted July 18, 2012 1) Your wiring probably has VD (voltage drop.) Try jumping the battery directly to the solenoid terminal. If it cranks easily then your wiring has one or more bad connection in the starting circuit. 2) Typically there are 2 wires on the battery negative terminal. The 4-gauge wire that goes to the engine block and a 10-gauge wire that connects to the firewall to ground the car body. The positive terminal only has the 4-gauge wire that goes to the starter motor. Quote Link to comment Share on other sites More sharing options...
Med Center Z Posted July 22, 2012 Author Share Posted July 22, 2012 Thanks for insights Im guessing what I found was a kill switch, I followed the mistery wires to a box the size of a tick tac box, had to tabs one red the other black, wasn't from factory. I pulled this device out. I'm going to check the readings of voltage Tuesday. At this current time when I turn to start the car I get a clicking notion an sound. Amp meters slightly just slightly going to.the navigate -45 but a/c,light, an radio all have power. I cleaned all the grounds an wizzy wheeled the bolts an connections free of rust or dirty connections. New cables, new battery but I wonder of I got a gauge wire one size to small...I pulled the harness that runs next to the starter looked fine no sign of overheading. Quote Link to comment Share on other sites More sharing options...
JSM Posted July 22, 2012 Share Posted July 22, 2012 1) Your wiring probably has VD (voltage drop.) Try jumping the battery directly to the solenoid terminal. If it cranks easily then your wiring has one or more bad connection in the starting circuit. 2) Typically there are 2 wires on the battery negative terminal. The 4-gauge wire that goes to the engine block and a 10-gauge wire that connects to the firewall to ground the car body. The positive terminal only has the 4-gauge wire that goes to the starter motor. ^^^^^^^^^^ This should be your simplest, fastest test. Quote Link to comment Share on other sites More sharing options...
Med Center Z Posted July 25, 2012 Author Share Posted July 25, 2012 I went to snug the harmonic balancer, it was lose. took me 4 turns to snug it up again. once it was snug and torqued, i couldnt turn the balancer. im going to assume my bottom end is blown. locked up. and im still not getting the starter to turn over. replaced the ignition, wiring, starter wiring, cables, and my 4 gage ground is now between my trany/motor not my trany/starter. ???? Quote Link to comment Share on other sites More sharing options...
Med Center Z Posted July 25, 2012 Author Share Posted July 25, 2012 Just pulled manifolds, cly 2 runner is full of water, rust, and junk. pulling head. Quote Link to comment Share on other sites More sharing options...
Miles Posted July 25, 2012 Share Posted July 25, 2012 I went to snug the harmonic balancer, it was lose. took me 4 turns to snug it up again. once it was snug and torqued, i couldnt turn the balancer. im going to assume my bottom end is blown. locked up. Is the trans in gear? Are you assuming that the engine is locked up? If true then the starter can not turn the engine over. and im still not getting the starter to turn over. replaced the ignition, wiring, starter wiring, cables, and my 4 gage ground is now between my trany/motor not my trany/starter. ???? Quote Link to comment Share on other sites More sharing options...
beermanpete Posted July 25, 2012 Share Posted July 25, 2012 Just pulled manifolds, cly 2 runner is full of water, rust, and junk. pulling head. Yeah, it sounds like the engine is locked up. Too bad about that. If you could turn the harmonic dampener separately from the crankshaft when the screw was only 4 turn out the woodruff key is likely missing. You should check on that. Quote Link to comment Share on other sites More sharing options...
Med Center Z Posted July 26, 2012 Author Share Posted July 26, 2012 I wonder if the carbs are rich an it washed out the rings? has flat top pistons an this is a early E88 Hemisphereical quench area. Quote Link to comment Share on other sites More sharing options...
NewZed Posted July 27, 2012 Share Posted July 27, 2012 Carbs running rich and water in the cylinders are not directly related. Water in a cylinder though, could have caused it to seize with rust. The water could have come from the outside or the inside of the engine, through the manifold or maybe a blown head gasket. Careful removing the head, if the water came from the inside, you might also have some rusted head bolts. Quote Link to comment Share on other sites More sharing options...
Med Center Z Posted July 27, 2012 Author Share Posted July 27, 2012 Yep head bolt was stuck on Cyl 2, pulled safly. I'm looking at swapping in - L28 overhauled, bored .040 over, new turbo own dished pistons, rings, balanced, polished rods, oem bolts. Early HE88, milled .010, felpro head Gasket, 280z stainless valves, new guides an seals. Ngk plugs/wires, 71 dizzy. Quote Link to comment Share on other sites More sharing options...
NewZed Posted July 27, 2012 Share Posted July 27, 2012 I'm not an expert on the details of the various heads, but an E88 head with 280X valves is probably essentially the same, or worse flow-wise since it's designed for smaller valves, than an N42 or N47 head. Your engine specs. look a lot like a 75-78 280Z engine. Might be easier to just buy a complete 280Z or 280ZX engine. Just guessing. If you're re-using your old parts to save money, it might make sense, but if you're building something for more power potential, I don't think there's much there. Quote Link to comment Share on other sites More sharing options...
Med Center Z Posted July 27, 2012 Author Share Posted July 27, 2012 240z had 1.65" intake and 1.30" exhaust. 280z-zx-zxt got 1.74" intake and 1.38" exhaust. I think the E88 of 73-74 or 260z got larger exhaust valves. The early E88 head cobustion chambers is similar to the E31 with the hemisphereical quench area a little deeper then the earlier head. I've researched only.to find talk over the early E88 being preferd sighting that the its valves are a little less shrouded than the E31. Am I missing something that i need to take into consideration on choosing the right valves? I had felt after research an reading that bigger valves are always better? I plan to just use some parts to get it running later ill update items as I.feel. I'm a student an have bills so its a build in progress. Quote Link to comment Share on other sites More sharing options...
NewZed Posted July 27, 2012 Share Posted July 27, 2012 Not sure why you're quoting valve sizes for other engines since you said you were installing 280Z valves in an E88 head. The whole hemispherical combustion chamber thing is just an old idea of perfection that has been hyped and marketed and recently re-marketed by Chrysler. Essentially meaningless. Besides, I don't think that the E88 chambers are hemispherical (whatever that really means). My point was that a 280Z head on an L28 block makes more sense than a 260Z head with 280Z size valves on an L28 block. Especially if you're on a student's budget with bills. The 280Z head combustion chamber will fit the bore correctly and the runners are already sized (I'm guessing here that the runners on an N42 or N47 head flow more volume than the runners on an E88 head - assuming the same size valves [280Z valves in this case] and similar cam. I could be wrong) for the valves. Just trying to help you save some time and money. Quote Link to comment Share on other sites More sharing options...
Med Center Z Posted July 27, 2012 Author Share Posted July 27, 2012 Thanks for the info maby my p90 head would be better Quote Link to comment Share on other sites More sharing options...
NewZed Posted July 27, 2012 Share Posted July 27, 2012 The P90 has a larger combustion chamber, same as the P79, than an N42 or N47 head (280Z). Used with dished pistons, for low CR, in the turbo application or flat tops, for higher CR, in NA. This calculator will give you some general ideas for brainstorming, it seems to be fairly accurate - http://www.ozdat.com/ozdatonline/enginedesign/ Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.