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cam gears

 
Old 08-31-2012, 12:03 PM
  #16  
Lizard928
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OK,

looking at your pictures, your gears are too far gone, get new ones from Rog, do NOT reassemble using those gears. I do have a few good sets of gears that I am going to get recoated, but if I sold you a set there would be a higher cost as you dont have good cores.
Also replace your oil pump gear with a new steel from Rog.

You will also be needing to do an intake and valve cover refresh as your knock sensors are both shot. This means that your car will have the timing reduced by 6 deg, therefor you will be running with much less power than you should have.
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Old 08-31-2012, 12:28 PM
  #17  
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Colin, those last pic's are gears from my junkbox, for illustration. Those are not Ian's gears.
(And oddly, the aluminum oil-pump gear was the best of the lot).

I couldn't tell from Ian's pic's how worn the cam gears were-- one or two teeth looked shiny, the others didn't look like much of anything.
It's not easy to photograph shiny things-- you need diffuse lighting.

Cheers,
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Old 08-31-2012, 01:04 PM
  #18  
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Originally Posted by Dads928 View Post
Roger, how do I know if the knock sensors need replacing and do I do that when I do the intake stuff. I was planning to do fuel lines and intake stuff next spring..
...
Ian, to properly diagnose the knock sensors you need access to a diagnostic tester or a Sharktuner. The connectors can be pretty ugly and still work, the critical parts are the sensors themselves, which are bolted to the top of the block under the intake.

Waiting until spring is fine for the knock sensors, and there is no advantage to combining it with the TB/WP job. IF one of the knock-sensors is dead, then the EZK pulls out 6 degrees of timing which costs some top-end power-- but does not cripple the motor, by any means. (I've got a flaky rear sensor on the S4, and I usually cannot tell when it pulls out the 6 deg's without looking at Sharktuner-- but I've got a lousy butt-dyno).

You've enjoyed driving the car, so finish the TB job and enjoy it some more, while you still have some decent weather.

My view on refreshing the intake differers somewhat from many folks here: There is no reason to make an epic job of it. The goal is to replace bad stuff. You need to remove the intake to get to it, which takes a few hours, but you do not need to replace, repaint, and replate everything in sight.

I think it is perfectly fine to pull the intake, clean and check everything and then replace just what needs replacing. A hose which is split, or which feels sticky and gummy, needs to be replaced. But a rubber hose that looks and feels like a rubber hose, is fine. And knock-sensors which checked OK before going in, and look OK, are OK.

If you are paying for labor, then that's a different story. You don't want to pay again for the labor if something is missed, and the mechanic sure as heck doesn't want to work for free.

Fuel lines are different, you can get to all of those without removing very much. Check them all, now, and immediately replace any that are showing cracks.

Cheers,
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Old 08-31-2012, 01:04 PM
  #19  
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Hello Jim,

you posted while I was writing my response.

I am able to tell from his pictures that they are seriously worn.
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Old 08-31-2012, 01:08 PM
  #20  
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also Jim, there is only one wire still in the connector for the front knock sensor, the other appears to be missing.
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Old 08-31-2012, 01:19 PM
  #21  
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Originally Posted by Dads928 View Post
Roger, how do I know if the knock sensors need replacing and do I do that when I do the intake stuff. I was planning to do fuel lines and intake stuff next spring..

How much is the oil pump gear, and do I need a new one and a crank gear???
I would do the fuel lines before driving the car any more. Too many cars have caught fire to risk driving with the original 20+ year old hoses.
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Old 08-31-2012, 01:43 PM
  #22  
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If you think those lines are bad, I just did them on an 82. I could literally rip the hose in half with my bare hands between the injectors and rail.
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Old 09-01-2012, 08:39 AM
  #23  
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Thanks - mine are not worn as badly but the coating is certainly gone. I am guessing it just hasnt had a chance to start wearing down yet. I think replacements are in order...
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Old 09-02-2012, 11:48 AM
  #24  
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what is the process for removal and replacement of the gears, do I need to take any special precautions so I dont affect the cam timimng or does the woodruf key lock it to stock?? I cant fihure it out from the WSM.
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Old 09-02-2012, 12:04 PM
  #25  
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Thanks for all of your help guys, I apologize but I missed a bunch of your responses when I replied last time. The knock sensor has two wires into it, its just a bad picture but a chunk of the plastic is missing. I do all of the wrenching myself, I have some basic skills and a lift so the labour costs are not an issue, just finding time. I spent some time as part of a race crew when I was a lot younger so the wrneching isnt really difficult just a lot dirtier than the race car was. Spent a good part of my youth tearing apart early 70's detroit iron, I miss all the elbow room under the hood....

My fuel lines are all solid looking but I know they will need to be replaced. I will do that over the winter along with the top end stuff.
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Old 09-02-2012, 12:34 PM
  #26  
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Originally Posted by Dads928 View Post
what is the process for removal and replacement of the gears, do I need to take any special precautions so I dont affect the cam timimng or does the woodruf key lock it to stock?? I cant fihure it out from the WSM.
The key locates the gear to the cam, but the keyway in the gear is oversized to allow for a few degrees of adjustment (plus/minus 7-8 crank-degrees IIRC). Once adjusted, the gear and cam are locked together with the center bolt, plus the three small screws that secure the ignition rotor.

With the rotor removed, you can see the tapped holes behind the slots in the cam gears. The tapped holes are on the 3-armed "spider" behind the gear, tightly keyed to the cam. The holes should be roughly centered in the slots. So when fitting new gears, start by centering those holes-- that will get you close.

Then you want to use Ken's (Porken) "PKV32'r" and "BumpStick" tools to set the cam timing properly. Ken's website is http://liftbars.com/, find the links on the left for "PK32v'r" and "BumpStick" and download the manuals. Roger (928sRus) sells Ken's cam tools.

Be sure to leave the engine set to 45-deg BTDC while fiddling with the cam gears. The marks won't line up-- transfer your marks from the old gears-- but the pistons are all safe. The cam lobes are under spring pressure and the cams like to move when you are not looking, with the belt removed.

Cheers, Jim
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Old 09-02-2012, 12:38 PM
  #27  
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I thought as much, thanks.. i will order the tools.. I have not done this type of work on an DOHC engine before. All my experience is with North American single cam v8s.

Finally updated my status, been meaning to for a couple of years...
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Old 09-02-2012, 01:59 PM
  #28  
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Clearly: the shiny part is visibly wider in the middle than at the ends, which means that it has worn deeper in the middle than at the ends.

Originally Posted by Lizard931 View Post
I am able to tell from his pictures that they are seriously worn.
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Old 09-02-2012, 03:14 PM
  #29  
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Before you remove the gear, put in a bolt that sticks out in one of the rotor mounting holes. Then measure the distance from the side of the bolt to the side of the slot in the cam gear with something like a digital caliper. I measured mine from each side of the bolt to each side of the slot. With these measurements you can put the new gear on using
a couple of temporary bolts in the other holes for the rotor & adjust it until you get the same measurement that the one you took off had. That
will get you close- to be exact use the Porken tool.
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Old 09-03-2012, 08:34 AM
  #30  
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Thanks Jim, sounds like a plan
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