Harmonic Damper question
Thread Starter
Pro
Joined: Apr 2005
Posts: 603
Likes: 2
From: Illinois, USA
Harmonic Damper question
I'm working on an RPM related vibration at 3500 and up and it gets worse the higher I go (most noted under load).
In order to see if the damper rotated, do I have to pull off the crank pulleys? Can it be inspected without major disassembly?
Thanks in advance.
Brian.
In order to see if the damper rotated, do I have to pull off the crank pulleys? Can it be inspected without major disassembly?
Thanks in advance.
Brian.
Melting Slicks
Joined: Nov 2001
Posts: 2,668
Likes: 43
From: Eastern US XX
Yes. Find top dead center of #1 cylinder (both valves closed) - the timing pointer should then point to 0 degrees. If not, it slipped.
Thread Starter
Pro
Joined: Apr 2005
Posts: 603
Likes: 2
From: Illinois, USA
That sounds good. What trick do you use to locate TDC on a cylinder? I would think that I'd be pulling the valve cover and dist. cap to get in the area -- unless you know of a method more precise that you've used.
Brian.
...and thanks.
Brian.
...and thanks.
Instructor
Joined: Apr 2006
Posts: 114
Likes: 0
From: Spring Texas
What you want to do is to make a ‘stop’ for the number 1 piston that will keep it from traveling all of the way up to the head.
They make a tool for this but can make one using an old spark plug and a bolt.
After breaking all of the ceramic material out of the sparkplug and breaking the tang that the spark jumps from, run the bolt down the sparkplug. The bolt should be big enough so it won’t come out.
Place the sparkplug tool in far enough in to stop the piston. Mark the HB. Then ‘By hand’ turn the crank all of the other way around till it touches again. Mark the HB. Now half way between the marks is TDC.
Good luck.
Race Director
Joined: Sep 2004
Posts: 11,874
Likes: 263
From: Arlington Va Current ride 04 vert, previous vettes: 69 vert, 77 resto mod
my home made TDC finder, these are anti foul extenders that you tap the inside for the carriage bolt to thread into from a local auto store
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