rallyeo Posted September 8, 2009 Share Posted September 8, 2009 I removed my timing cover this weekend to replace a blown gasket and now it won't start. I have seen many posts about checking cam and timing chain position, but none on where the dizzy gear should be - Currently, when the #1 cylinder is at TDC, the rotor is pointed at the #1 also. I did not remove the oil pump or touch the timing chain when the cover came off, but the dizzy gear did move a bit. Does this make a difference? BTW , it's a 77 280z EFI. Quote Link to comment Share on other sites More sharing options...
Administrators BRAAP Posted September 8, 2009 Administrators Share Posted September 8, 2009 Are you getting spark at the spark plugs? If not, start troubleshooting why the plugs aren't sparking, i.e coil power, EFI power, etc. (just in case, firing order is 1-5-3-6-2-4). If the plugs are sparking while cranking the engine, then good chance the dizzy drive still may not be clocked correctly, (so longs the EFI is also firing the injectors. They will click audibly while starting the engine, and also verify fuel pressure at the injectors). If the front cover was removed, even with the quill shaft in the front cover, when it went back on, it still can easily move and be off a tooth. If you are getting spark at the plugs, use timing light while a helper cranks the engine to verify the spark is happening at the correct time, near TDC. You mentioned the rotor is pointing to #1 with #1 piston at TDC. Is that TDC of the firing/compression stroke or TDC of the valve overlap event? This is to easy figure out. Remove the valve cover and look at the front 2 cam lobes for the #1 cylinder. If the lobes are pointing up equal amounts, (intake and exhaust lobe both point mostly up at the same time), that is the TDC of the compression stroke and your timing should be close. If the lobes are both pointing down by the same amount, that is TDC of the valve overlap period and your dizzy is phased 180 degrees from your cam, i.e. all of your plugs are firing on the valve overlap period! Quick and dirty fix for that is swap all the plug wires to the opposite side of the dizzy. I.e. swap plug wires 1&6, swap wires 2&5, and swap wires 3&4. The more correct fix would be re-clock your quill shaft 180 degrees, either will get the ignition spark at the correct time for the cylinder. Hope that helps, Paul Quote Link to comment Share on other sites More sharing options...
rallyeo Posted September 8, 2009 Author Share Posted September 8, 2009 Big help, thanks! I am getting spark, forgot to mention that earlier - I'll have to go and check everything tomorrow aftenoon, it's getting late... back to work in the morning! Quote Link to comment Share on other sites More sharing options...
ktm Posted September 8, 2009 Share Posted September 8, 2009 A FSM and/or Haynes manual will show you how the dizzy spindle should be orientated. Quote Link to comment Share on other sites More sharing options...
zuum Posted September 13, 2009 Share Posted September 13, 2009 hey BRAAP, you forgot to mention the 11:28 position. With the distributor removed, you see the drive spindle, it has an offset 'tab', the smaller of the two half round shapes should face forward and the 'tab' should be pointing to about 11:28 o'clock. Borrowed this image from here http://www.geocities.com/inlinestroker/ Quote Link to comment Share on other sites More sharing options...
Administrators BRAAP Posted September 13, 2009 Administrators Share Posted September 13, 2009 hey BRAAP, you forgot to mention the 11:28 position. With the distributor removed, you see the drive spindle, it has an offset 'tab', the smaller of the two half round shapes should face forward and the 'tab' should be pointing to about 11:28 o'clock. Borrowed this image from here http://www.geocities.com/inlinestroker/ Thanks for helping. Being as the dizzy will only engage the quill shaft in one position, the rotor position for TDC #1 pretty much already verified that quill shaft alignment. Chance of his quill shaft being TDC #1 on valve overlap is about 50-50.. Quote Link to comment Share on other sites More sharing options...
zuum Posted September 13, 2009 Share Posted September 13, 2009 Thanks for helping. Being as the dizzy will only engage the quill shaft in one position, the rotor position for TDC #1 pretty much already verified that quill shaft alignment. Chance of his quill shaft being TDC #1 on valve overlap is about 50-50.. Unless, he removed the plugs wires and re-oriented them according to what he 'thought' was number 1 based on where the rotor was pointing. Not that I think the OP is stupid, its an easy mistake, but he may have it pointing at A plug and assume that its number 1 (doesn't mean it will run). I know you know this stuff... so I am just mainly trying to be helpful here. I can't count how many datsuns I've fixed in the last 10 years because of this. I had a 510 that was built for autocross earlier this year, the guy who owned it before me took it to a place called "Rally Round" in seattle for some repairs (brakes, suspension bushings and tune up with pertronix unit), well car never right to me... so I pulled the dizzy and the dizzy drive spindle was off a tooth, with the adjustment settings MAXED OUT to compensate (both the 10mm and the 8mm), fixed 'er right up I did. 521 earlier this year 180degrees off, the guy fought with the thing for 6 months thinking it was the carb, so he sold it to me cheap, took me all of 30mins to figure it out and fix it. The 240z I have now was off by 90degrees when I got it, the plug wires were re-oriented to compensate, as well as the timing adjustment maxed out. Quote Link to comment Share on other sites More sharing options...
rallyeo Posted September 14, 2009 Author Share Posted September 14, 2009 Got the car running last night, thanks to all for the assistance - the picture was a huge help Quote Link to comment Share on other sites More sharing options...
zuum Posted September 14, 2009 Share Posted September 14, 2009 wait, so what was the problem? You gotta leave the conclusion for searchers! Quote Link to comment Share on other sites More sharing options...
rallyeo Posted September 15, 2009 Author Share Posted September 15, 2009 Well it seems that I was off by a tooth ... or 2 or 3. It took a minute to figure out how to get the cover back on with the spindle in position, basically I needed to turn the spindle back (to the left) about half way since the spindle turns when the cover goes back into position. Now I have a small leak in the oil pan area so that gasket will probably be my next project...... Quote Link to comment Share on other sites More sharing options...
zuum Posted September 15, 2009 Share Posted September 15, 2009 Did you pull the cover to turn the spindle? It can be adjusted by dropping the oil pump. Quote Link to comment Share on other sites More sharing options...
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