S2000 Under The Hood S2000 Technical and Mechanical discussions.

DIY Valve Adjustment

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Old Apr 4, 2016 | 11:40 AM
  #141  
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Just pulled my valve cover, cams are not reversed.
Can't see any trace or marks on any nuts or bolts that suggest anything ever been removed. I guess it's possible to not leave any marks though.
~2.6 degrees doesn't sound to good, thanks for checking that Billman.
I guess I will start pulling out the cams tomorrow, one good thing about this is now I get a chance to torque that cam trigger wheel I swapped for my kpro installation.
Manual says to loosen all the rocker arm adjusting screws before removing the camshaft holders.
Is this not needed since you said I wont even need to adjust the valves Billman?
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Old Apr 4, 2016 | 12:03 PM
  #142  
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I always get spooked when tightening the cam caps because you have to press down on the cams to install them if you have you valve clearance set. I always backed off the jam nuts so I could tighten the cam caps perfectly, but that's personal preference. Is it ok to install the cam caps like this thought? I mean if you triple check that all the bolts are tightend to spec afterwards it should be ok right?
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Old Apr 4, 2016 | 01:16 PM
  #143  
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I have never backed off the adj nuts to remove the cams. Just tighten all bolts slowly and equally, or you will break the cam caps.
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Old Apr 4, 2016 | 11:21 PM
  #144  
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I will probably loosen them then, I'm nervous enough about removing all these things.
My head keeps spinning about how the firing order could have worked in my engine though, stock is 1-3-4-2 but with my cam gears switched my engine (or valves) would be in 4-2-1-3 order.
How could it have been running like this if injectors and sparks would be happening in the wrong order?
I keep wondering if anything else could have been switched as well but I cant figure out what.
Thanks for your support.
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Old Apr 5, 2016 | 03:13 AM
  #145  
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Nothing has changed firing order wise.

As of now, the valves are being opened 2.6 degrees early or late.
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Old Apr 5, 2016 | 05:04 AM
  #146  
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Yes I agree firing order is constant, but cam lobes changed 180 degrees is what's causing me to scratch my head
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Old Apr 5, 2016 | 05:10 AM
  #147  
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The cam lobes have not changed 180, only the marks on the gears.

The cams are running only 2.6 degrees out from their original clock position.

Think of it this way, let's go over the job.

-set engine to tdc1 firing, white pointer on crank, timing marks opposed 180, not together (since yours are on wrong)

-cams will be in proper position (well, 2.6 degrees away from it)

-swap gears without changing cam position, now marks are pointing towards each other. Due to a slight timing change from gear to gear, each cam will move slightly.

It takes a full tooth for the engine to go out of sync. Being that you are out only 1/3 tooth, she runs.
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Old Apr 5, 2016 | 06:19 AM
  #148  
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Originally Posted by flanders
I will probably loosen them then, I'm nervous enough about removing all these things.
My head keeps spinning about how the firing order could have worked in my engine though, stock is 1-3-4-2 but with my cam gears switched my engine (or valves) would be in 4-2-1-3 order.
How could it have been running like this if injectors and sparks would be happening in the wrong order?
I keep wondering if anything else could have been switched as well but I cant figure out what.
Thanks for your support.
Remember, this is a 4-stroke engine. So the pistons come up to TDC twice for every ignition. Easy way to see this is if you take the firing order of most cars --- 1-3-4-2, for the S2000 --- take the first two numbers and put them on top of the second two numbers, you get:

1-3
4-2

1 & 4 are at TDC at the same time. 1 has both valves closed (ignition) and 4 has both valve overlap-opened (start of intake). 2 & 3 are at BDC. (1 & 4) and (2 & 3) cylinders are 180-degrees out-of-phase of each other.

https://www.youtube.com/watch?v=M1h9eU9YH5o
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Old Apr 5, 2016 | 08:13 AM
  #149  
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Went out in my garage and turned the crank a few cycles and I think I got my head in sync now.
Thanks guys
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Old May 22, 2016 | 07:50 PM
  #150  
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Just finished a valve adjustment on my '06, prompted by a CEL and misfire codes. What a world of difference it made!

The most difficult problem I had was getting the PCV and breather hoses off. Even with pliers, it took some serious wiggling to get them off the nipples.

Another tip -- if you're going to replace the spark plug seals, use a rubber mallet and one of the old seals to install the new ones so that they are seated all the way in.
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