924Board.org

462avi · Posted: Thu Aug 28, 2008 11:52 am Post subject: Interesting timing issues

So I have been chasing problems around the turbo and decided to get back to basics. I went to check the timing and the marks are not lining up correctly. The dampener and the flywheel marks line up as does the #1 at tdc. However when I go to set the cam timing mark in line with the valve cover pointer it binds i.e. valves hitting pistons. So I pull the valve cover and what I find is the intake valve lobe all the way down when the mark is lined up. Am I missing something here? I checked what is going on with my car against a spare cylinder head and find the same situation. Is there a difference between the n/a cam sprocket and the turbo? I would presume based on other engine experiences that the valves on #1 should be shut. Any help would be appreciated.

Geoff
_________________
2005 C230K
2002 grand cherokee with 4.7L

Paul · Posted: Thu Aug 28, 2008 12:26 pm Post subject:

Is the camshaft pulley installed backwards?

Are you using the correct mark on the camshaft pulley?
_________________
White 87 924S "Ghost"
Silver 98 986 3.6l 320 HP "Frank N Stein"
White 01 986 "Christine"
Polar Silver 02 996TT. "Turbo"
Owned and repaired 924s since 1977
Porsche: It's not driving, it's therapy.

Paul · Posted: Thu Aug 28, 2008 12:31 pm Post subject:

_________________
White 87 924S "Ghost"
Silver 98 986 3.6l 320 HP "Frank N Stein"
White 01 986 "Christine"
Polar Silver 02 996TT. "Turbo"
Owned and repaired 924s since 1977
Porsche: It's not driving, it's therapy.

462avi · Posted: Thu Aug 28, 2008 1:11 pm Post subject:

Thats the thing, the dot is actually on the front of the pulley not on the back. Also the spare head I have is assembled the same way. The other thing I notice is that on you timing sprocket your mark is in a valley while mine is on a tooth.

Geoff
_________________
2005 C230K
2002 grand cherokee with 4.7L

462avi · Posted: Thu Aug 28, 2008 1:23 pm Post subject:

Got it. The pulley on the spare head actually has the dot on the rear. I am going to swap them out. The one on the car is spotless but no dot so out it comes. I guess this one was an odd ball.
Thanks Paul!

Geoff
_________________
2005 C230K
2002 grand cherokee with 4.7L