mainboyd Posted October 23, 2015 Share Posted October 23, 2015 (edited) Ok so I been searching for a few days now on why my distributor rotor is facing the complete opposite direction then where it should be. Long story short, I have a 240z with a L28ET motor and it was running perfectly 2 weeks ago, had it sit for a week then tried starting it again and all I got was back firing through the exhausts pipe and it did not want to start. Before having it sit for a week I was working on getting the distributor shaft perfect by dropping the oil pump and placing the shaft in the right position. This was done just before I had the z sit for a week. Anyways I decided to take the distributor cap off and noticed the rotor is facing completely the wrong way. I have no idea how it happened or if it was always that way. So I followed the manual and everything online that I can find to properly place the shaft correctly and I am positive that I have done that correctly. The only thing is that when I put the distributor back on the rotor is still facing the wrong way. Why?? And why would all of a sudden it won’t start? I verified that the motor is at TDC by looking at the two front camshaft lobes to see if they are pointing upwards and the notch on the crank pulley is at 0. Either way, I set the distributor shaft in the correct position so that is what should determine where the distributor rotor is facing/starting before even trying to start or run the car. Also, there is only one way the rotor can be bolted on to the shaft because there is only one tapped hole on one side of the shaft, the hole does not go through the shaft. I have attached pictures of how everything is set. sorry for the pictured coming out sideways. I dont know why they came out like that. Edited October 23, 2015 by mainboyd Quote Link to comment Share on other sites More sharing options...
wolfalp1592 Posted October 23, 2015 Share Posted October 23, 2015 When you drop the oil pump you can put it back 180 out. That will cause the button to be 180 off when at TDC Quote Link to comment Share on other sites More sharing options...
mainboyd Posted October 23, 2015 Author Share Posted October 23, 2015 I understand that I can do that but I'm wondering why I'm having to do that when everything was installed correctly? Are the distributor shafts installed differently for a 1981 L28ET compared to an 82 or 83? (I believe I have an 81 motor) Quote Link to comment Share on other sites More sharing options...
z240 Posted October 23, 2015 Share Posted October 23, 2015 (edited) Stop worrying about why its wrong and get the shaft in the position so that the dizzy points to cap hole #1 at TDC. You know how to get TDC, so put it back there, pull the pump and get the shaft set. If its any consolation, and so I don't come across as a total a$$, I STILL have trouble getting all the details of timing right from time to time. Just accept your human weakness and make it right. Edited October 23, 2015 by z240 Quote Link to comment Share on other sites More sharing options...
mainboyd Posted October 23, 2015 Author Share Posted October 23, 2015 I'll set the shaft 180° from where it should be. I did not know if that would be OK to do or not. I was just going to have the #1 sparkplug wire start where the rotor is currently at but I'll just turn the shaft. Thanks wolfapl1592 and z240. Kind of afraid to ask because I don't want to get flamed for it but I am interested to know how it is 180 off. I'm not the type of person that just fix the problem and don't care why or how it happened. Quote Link to comment Share on other sites More sharing options...
Milenko2121 Posted October 23, 2015 Share Posted October 23, 2015 (edited) I'll set the shaft 180° from where it should be. I did not know if that would be OK to do or not. I was just going to have the #1 sparkplug wire start where the rotor is currently at but I'll just turn the shaft. Thanks wolfapl1592 and z240. Kind of afraid to ask because I don't want to get flamed for it but I am interested to know how it is 180 off. I'm not the type of person that just fix the problem and don't care why or how it happened. It's most likely you weren't on compression stroke when you installed it so that's why it was 180deg off. Edited October 23, 2015 by Milenko2121 Quote Link to comment Share on other sites More sharing options...
mainboyd Posted October 23, 2015 Author Share Posted October 23, 2015 Yes I believe that might be it but man I swear I thought I had the shaft placed in the same way before but just slightly turned by one tooth... oh well I'll just turn it 180 now. Thanks everyone. Quote Link to comment Share on other sites More sharing options...
johnc Posted October 23, 2015 Share Posted October 23, 2015 One of the following is the cause: 1. Installed incorrectly. 2. Broken distributor shaft 3. Shaft gear spun on the shaft 4. Shaft gear stripped 5. Drive gear on crank stripped 6. Broken crank 7. Tang on shaft snapped off 8. Rotor broken or stripped Quote Link to comment Share on other sites More sharing options...
wolfalp1592 Posted October 23, 2015 Share Posted October 23, 2015 When I reinstalled the head on my 82 mine was 180 off, and I checked everything, as previously mentioned I wasn't on the compression stroke, to make sure I did what I think you are suggesting and moved my spark plug wires, ran perfect. It took 20 min to drop oil pump and rerun plug wires. The oil shaft does spin very easy when reinstalling and I had to be careful not to let it rotate as I installed the distributor. Quote Link to comment Share on other sites More sharing options...
NewZed Posted October 23, 2015 Share Posted October 23, 2015 Long story short, I have a 240z with a L28ET motor and it was running perfectly 2 weeks ago, Before having it sit for a week I was working on getting the distributor shaft perfect by dropping the oil pump and placing the shaft in the right position. This was done just before I had the z sit for a week. had it sit for a week then tried starting it again and all I got was back firing through the exhausts pipe and it did not want to start. Anyways I decided to take the distributor cap off and noticed the rotor is facing completely the wrong way. I have no idea how it happened or if it was always that way.. Why?? And why would all of a sudden it won’t start? I re-ordered your story to chronological. Looks like you were disturbed that something about the distributor wasn't where you thought it should be (you never said what was not right) so you messed with your perfect-running engine and got lost in the details. So, nothing broke, you just moved your good parts to the wrong places. That explains "why". If you're sure that the distributor is exactly 180 degrees off then the fix is easy - just run it with the wires 180 out or drop the pump and flip it 180. Quote Link to comment Share on other sites More sharing options...
mainboyd Posted October 23, 2015 Author Share Posted October 23, 2015 To clarify why I decided to try to get the shaft "perfect" before having the car sit was because I used a timing gun (not sure if it was a good idea) to see where I was at in my timing and it was off. I was not able to just simply turn the distributor from the top to correct it so that's when I dropped the oil pump to turn the shaft one tooth to see if I can perfect the timing. Note to self: if there is nothing wrong with it then leave it alone!!!! Thanks again everyone. Quote Link to comment Share on other sites More sharing options...
NewZed Posted October 23, 2015 Share Posted October 23, 2015 Sorry, I didn't really look at your pictures. What timing number were you trying to hit? Just curious, since you're working with the ECCS system. Quote Link to comment Share on other sites More sharing options...
mainboyd Posted October 23, 2015 Author Share Posted October 23, 2015 I was just trying to shoot for any number on the scale because it wasn't even hitting the scale, past the 30 mark when using the timing gun. Quote Link to comment Share on other sites More sharing options...
NewZed Posted October 23, 2015 Share Posted October 23, 2015 Since you're rotor is way off, the plug wires may have been rotated to make the engine run. You might try using different plug wires to find the new "#1" wire. Since the engine runs right, one of your plug wires will probably give you a light in the range. I can see why you decided to mess with it now. You might be able to still set timing, just in a non-spec. way. Quote Link to comment Share on other sites More sharing options...
mainboyd Posted October 23, 2015 Author Share Posted October 23, 2015 Well as of right now the car does not start. So I'm going to try to turn the shaft 180 and see if that will work. Quote Link to comment Share on other sites More sharing options...
johnc Posted October 24, 2015 Share Posted October 24, 2015 I suggest you start over. Put cylinder #1 exactly at TDC and go from there. Quote Link to comment Share on other sites More sharing options...
mainboyd Posted October 24, 2015 Author Share Posted October 24, 2015 (edited) I suggest you start over. Put cylinder #1 exactly at TDC and go from there. Well lets take a step back and think about this here. First what I am trying to figure out is why my distributor rotor is off 180 degrees. Lets leave "TDC" out of the equation for now because, and correct me if I'm wrong, the motor does not need to be at TDC if I'm trying to determine why my rotor is off. If you think about it, the placement of the rotor is determined by the placement of the shaft. Technically the shaft can be placed in any position (but there is only one correct position if wanting the car to start). So by taking "TDC" out of the equation it makes it a little easier to find out why the rotor is facing the wrong direction because we are not having to worry about if we are at TDC any more. So by looking at the three pictures I put together on this specific post I have made it a little easier to see where my shaft is placed by making the important things to realize in RED. Now when looking at the pics I believe that the shaft is in the correct position according to the manual and what I have searched for online. However, when I place the distributor on, the rotor is then pointing in the wrong direction (keeping in mind that the distributor can only fit one way due to the machined end of the shaft and of the distributor). AND THIS IS WHAT LEADS ME TO WHY I STARTED THIS TOPIC. Edited October 24, 2015 by mainboyd Quote Link to comment Share on other sites More sharing options...
NewZed Posted October 24, 2015 Share Posted October 24, 2015 The simplest answer (Occam, Einstein, KIS, whatever) is that somebody pounded/manipulated your rotor on to the distributor shaft 180 off. Remove the rotor from the top of the shaft and see what's under there. Consider what connects the top of the shaft to the bottom, on a ZX trubo CAS/distributor. Never had one myself so don't know how they're put together. Quote Link to comment Share on other sites More sharing options...
NewZed Posted October 24, 2015 Share Posted October 24, 2015 Rotated your first pictures just to show what you're talking about. The oil pump drive quill looks right but the top of the CAS shaft with the rotor is 180 off. It's either the rotor or the top of the CAS shaft that's not right. If the bottom fits, that's all that's left. Quote Link to comment Share on other sites More sharing options...
NewZed Posted October 24, 2015 Share Posted October 24, 2015 Actually, looking at the pictures, it looks like the rotor is more like ~160 degrees off, not 180. Hard to be sure since the pictures aren't from exactly the same position. Something weird with the CAS shaft or the rotor fit. Quote Link to comment Share on other sites More sharing options...
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