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Barn Find 91 GT

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Old 02-21-2017 | 10:05 PM
  #166  
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that is a trigger for the Hall sensor thats bolted to the rear side of the cam tower housing,
put it back in or the computer will not be able to tell when the cam reaches TDC.
NOTE their is only one of these and its installed on the right side cam
Old 02-21-2017 | 11:49 PM
  #167  
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Thanks Stan, with all the stupid that went into previous repairs I was worried someone "forgot" to put one of them back on!
Old 02-22-2017 | 12:10 AM
  #168  
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What a great read. Keep up the good work. Awesome

James
Old 02-22-2017 | 03:48 AM
  #169  
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By the way if the Hall trigger is not working and/or the knock sensors you immediately kiss goodbye to 6 degrees of ignition advance across the board [not good].

Given your efforts to date removing the inlet manifold and doing what is necessary is common sense. If it is needed, refinishing of the inlet manifold and cam covers is also highly desirable/necessary at this stage in life and makes all the difference in the world presentation wise.

Of course the $$$'s are rolling but then I am sure you well understand this by now.

Rgds

Fred
Old 02-22-2017 | 11:39 AM
  #170  
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Originally Posted by FredR
By the way if the Hall trigger is not working and/or the knock sensors you immediately kiss goodbye to 6 degrees of ignition advance across the board [not good].

Given your efforts to date removing the inlet manifold and doing what is necessary is common sense. If it is needed, refinishing of the inlet manifold and cam covers is also highly desirable/necessary at this stage in life and makes all the difference in the world presentation wise.

Of course the $$$'s are rolling but then I am sure you well understand this by now.

Rgds

Fred
Ugh, all too well.
Old 02-22-2017 | 02:16 PM
  #171  
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Not paying too much attention, I've tried installing one on the driver side (left side) and physically it will not fit as casting from the head will interfere with the un needed trigger wheel/disk.
Old 02-22-2017 | 05:57 PM
  #172  
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did you all see this?

guy's wife discovers her husband's 928 was owned by George Harrison...

https://rennlist.com/articles/george...ed-to-auction/
Old 02-28-2017 | 11:40 PM
  #173  
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Despite being down with the flu last week, I managed to finish pulling the intake on Saturday



With the manifold removed I was able to pull the water bridge and oil filler, looks like the most major oil leak was the breather hose that connects to the filler closest to the front of the car.













I believe at some point after my 84 Carrera was built Porsche started spec'ing Bavarian ear wax for all Amp connectors used in the engine compartment so the two knock sensors are the first of many that will be replaced. Every connector I touch degrades to paste as soon as its touched so I'm now in for a minimum of the Hall and CPS in addition to the two knock sensors already replaced.

The paint on the intake is worse than it appears in the pictures, it is delaminating in multiple places so I'll likely be disassembling it and sending it out for powder coating. Seems like the current recommendation is to fully degrease it inside and out before sending it off and then requesting that it be blasted with aluminum oxide. I'll do some additional reading before making the call but if anyone has any other recommendations please chime in!
Old 03-01-2017 | 10:47 AM
  #174  
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Don't use aluminium oxide.
Old 03-01-2017 | 10:55 AM
  #175  
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Originally Posted by mskar
Seems like the current recommendation is to fully degrease it inside and out before sending it off and then requesting that it be blasted with aluminum oxide. I'll do some additional reading before making the call but if anyone has any other recommendations please chime in!
I would advise not blasting the intake with any media at all. Strip it by hand, with wire wheel, sanding, or whatever, but no media blasted to an intake at all, ever. Far too many engines destroyed by that method.
Old 03-01-2017 | 10:57 AM
  #176  
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I hate to add to your task list, but now is a great time to repl the CPS in the rear of the asm, and also address all the fuel lines. Also find the right solution for the heater valve. They are all right there accessible now.
Old 03-01-2017 | 11:03 AM
  #177  
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CPS is on the list, connector turned to crumbs. Will be sure to read up on the heater valve. Is there some sort of test or is this yet another throw away part?
Old 03-01-2017 | 11:06 AM
  #178  
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You can use a mity-vac to test if the heater valve is opening and closing like it should. The other failure would be a leak, not sure how you would test for that with the car not running or not able to pressurize the cooling system. That being said, it's a very cheap part (I know, very cheap x LOTS is no longer very cheap, been there )
Old 03-01-2017 | 11:28 AM
  #179  
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Ask Roger for the latest iteration of the heater valve. It really doesn't matter if the vac actuator works, it's the vane or solenoid inside the water path that often goes bad. I think the latest is we are using a solenoid type from a Ford Tbird, but Roger will have the latest scoop.
Old 03-01-2017 | 08:54 PM
  #180  
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Thanks Guys, I received Roger's intake spreadsheet today. I'm going to do some additional disassembly this weekend and take an inventory of what I appear to need. I appreciate all of the feedback!


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