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Home » Public Forums » GMCnet » [GMCnet] Simple way to check the condision of your timing chain
[GMCnet] Simple way to check the condision of your timing chain [message #329437] Fri, 23 February 2018 11:48 Go to next message
BobDunahugh is currently offline  BobDunahugh   United States
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Registered: October 2010
Location: Cedar Rapids, IA
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But it takes two people. Unless you have an inspection camera. Pull off your distributor cap. Get a 1-1/8 socket, and breaker bar. Put the socket on the bolt that's holding the crankshaft harmonic dampener on. Rotate the crankshaft clockwise a little. Then rotate the crank counterclockwise. As it just starts to rotate in the counterclockwise direction. Use a hammer to tape on something to indicate when the crank started to turn. The person that's watching the distributor rotor then can note if there is any delay between the tap, and the movement of the rotor. The amount of delay will give you an IDEA of the condition of the cam chain. There should be no delay. Using an inspection camera for the person doing the rotating while looking at the rotor with the camera is best. These cameras are to me a must have tool. Bob Dunahugh
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Re: [GMCnet] Simple way to check the condision of your timing chain [message #329438 is a reply to message #329437] Fri, 23 February 2018 11:57 Go to previous messageGo to next message
jhbridges is currently offline  jhbridges   United States
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Registered: May 2011
Location: Braselton ga
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I have one on order from the heathen chinese, I haven't traced it. Due in a couple weeks.

--johnny


Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons. Braselton, Ga. I forgive them all, save those who hurt the dogs. They must answer to me in hell
Re: [GMCnet] Simple way to check the condision of your timing chain [message #329442 is a reply to message #329437] Fri, 23 February 2018 13:42 Go to previous message
Dave Stragand is currently offline  Dave Stragand   United States
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Registered: October 2017
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On my '68 Caddy (472ci) I could simply reach in with a finger and feel
the slop in the chain (engine OFF, of course). I was watching a youtube
video on replacing the chain on the 455 and it looks like it's similar.

https://www.youtube.com/watch?v=B6rb5igyBWo

It looks like on my 403, I could even check this from inside the coach
by just removing the fuel pump. Not as good as Bob's more exact method,
but do y'all think it may be a good idea to check this way while you're
changing the fuel pump?

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1978 Transmode (403) Pittsburgh, PA
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