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Old Apr 3, 2014 | 01:17 PM
  #16  
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Originally Posted by jhg41977
With a 993 and power steering, I don't think you can swap cams side to side and still have everything bolt up properly. Can someone confirm?
I think you're correct, the rearward ends of the left and right cams appear very different - see pics below from my own project.

First pic is the right (power steering) cam, it has a central slot with a large bolt hole in the middle for power steering takeoff.
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Old Apr 3, 2014 | 01:17 PM
  #17  
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Originally Posted by bcameron59
Doubtful, as he used the factory timing tools and noted:
still a possibility if you ask me.

http://www.pcarworkshop.com/index.php/Not_quite_there
http://www.pcarworkshop.com/index.php/Cranking_it_up
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Old Apr 3, 2014 | 01:19 PM
  #18  
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Second pic is the left cam, the slot is offset and there are three small holes which may have something to do with timing (I used the backdated method).

Seem to be having problems uploading multiple pics in one post, so had to post this separately.
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Old Apr 3, 2014 | 01:40 PM
  #19  
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Originally Posted by Quadcammer
Granted, possible if OP's recollection is in error.

It was with MikeJ's tribulations in mind that I had originally asked about cam timing. OK, actually my own tribulations - after reassembly I discovered that I had timed BOTH cams 180 degrees out (clearly I am not a man for half measures, unlike MikeJ who only timed ONE side 180 out. ).

I knew that when cyl 1 was at TDC the rotors should point at #1, but they were pointing at #4. Had to pull everything apart and re-time the cams (I went with the backdated version). At least the engine was still out of the car.

However, if OP is CERTAIN the cams are timed correctly it doesn't hurt to eliminate other possible causes first. Going back to check cam timing probably means an engine drop and chain cover removal, not fun.
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Old Apr 3, 2014 | 01:51 PM
  #20  
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My bet it the distributor is out 180 degrees. Here is what to do.
  • Put engine at TDC #1.
  • to verify this turn engine to Z1 on crank pulley.
  • Then pull the lower valve cover on bank 1-3.
  • Verify that both the Intake and Exhaust valves for #1 are closed.
  • If they are not closed then the engine is at TDC #4.
  • Rotate engine 360 degrees, then verify #1 valves are closed.
  • Check the distributor and adjust so the rotor is pointing to #1 (Mark on distributor).
  • If not remove distributor rotate to #1 and reinstall.

Be careful when Installing the distributor as you can quite easily be 1 tooth out if you try and install it with the rotor pointed at #1, You need to turn the rotor counter clockwise just slightly prior to pushing the distributor home. When you do this it will line up the #1 perfectly.

Hope this helps.
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Old Apr 3, 2014 | 01:51 PM
  #21  
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Originally Posted by swmic
Pull a spark plug and see if you have spark. It will also allow you to see if you have fuel getting there. I would also pull a cap off to verify timing. If that checks out, I would check compression to see if the valve timing is correct.
What he said - start by verifying spark and fuel, which is fairly easy. Make sure your spark plug is near but not touching the engine case, and well separated from its cylinder to prevent kaboom...

If those are ok, check out your distributor suspicions. If cylinder 1 is at TDC (can you verify with the screwdriver test, as you turn engine by hand?), dizzy rotor should point at cylinder#1. However, it appears that you have already confirmed this, so not sure what else you would check on the distributor setup:

Originally Posted by jhg41977
To install the distributor I turned the motor to tdc number one cylinder. I verified that the valves were closed when the crank was positioned at tdc. I installed the distributor, aligning the rotors with the marks on the distributor housing.
Due to the helical gearing on the dizzy shaft, it will twist a few degrees on re-insertion, but if everything aligns as you describe above, you will have compensated for this.

i hate to ask, but are you CERTAIN that prior to disassembly, cylinder 1 was at TDC when you marked where the rotors pointed on the distributor case?

I have to ask because this is how I figured out that I had timed BOTH cams 180 degrees out. On reassembly rotor was pointing at 4 when cyl 1 was TDC.
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Old Apr 3, 2014 | 01:54 PM
  #22  
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Great minds think alike Brian.......

Screwdriver also works, I just don't like sticking anything into my cylinders
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Old Apr 3, 2014 | 02:03 PM
  #23  
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But if he is only 1 tooth off it should start, just run horribly....correct?
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Old Apr 3, 2014 | 02:06 PM
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Originally Posted by trophy
Great minds think alike Brian.......

Screwdriver also works, I just don't like sticking anything into my cylinders
Your instructions & method are better, actually. My excuse is that I'm home with flu and my cognitive skills are impaired due to fever.
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Old Apr 3, 2014 | 02:58 PM
  #25  
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JHG41977, if you have eliminated any possible issues with spark and fuel, I'd recommend a double check using Stephen's instructions above. This will verify both dizzy alignment and left side cam timing.

At the same time you may also want to check both valves on cylinder 4 to verify the right side cam is also timed correctly, ie not 180 degrees out. IIRC, #4 intake should be open, and exhaust closed.

Hate to say it, but the wheezing / catching sounds a lot like what MikeJ described in his rebuild thread when he had one side out 180 degrees. Hopefully he will see your video and can comment himself.
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Old Apr 3, 2014 | 03:11 PM
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Originally Posted by OverBoosted28
But if he is only 1 tooth off it should start, just run horribly....correct?
pretty much
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Old Apr 3, 2014 | 05:55 PM
  #27  
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Originally Posted by OverBoosted28
But if he is only 1 tooth off it should start, just run horribly....correct?
It is potentially out by 15 degrees or so, so it may or may not start.

Edit: The gear on the bottom of the distributor has 12 teeth, so 1 tooth is 30 degrees. I doubt it would start.

Last edited by trophy; Apr 3, 2014 at 06:00 PM. Reason: New Information....
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Old Apr 3, 2014 | 08:53 PM
  #28  
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TDC happens twice in a cycle. I'd vote for making sure dizzy is at 1 on the right stroke.

I assume when you say "pulled DME", you mean the relay? If you unhooked the DME, a wire could've broken.

Cams are timed on different 360 degree rotations in the 720 degree cycle.
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Old Apr 3, 2014 | 08:55 PM
  #29  
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I had to help a neighbor out, haven't finished up the car yet. I did find the cams are correct to tdc, in the correct cycle. The distributor was out by about 60 degrees. I am not sure how the hell I managed that. Almost back together.
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Old Apr 3, 2014 | 09:06 PM
  #30  
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Part of the fun of rebuilding. When I built my 3.2, I sent the injectors out for cleaning. 2 months before firing it up. I then learned that freshly cleaned injectors don't like to sit for two months.
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