why can't I time my truck??

[tomslik]

Well I spent some more time on the timing, the mechanical advance works and as you rev the motor you can see the timing mark move also the weights are free to move and return to the center, I removed the dist cap and rotor, I turned the engine over well my boy did and felt for compression stroke and for the rotor to point to the number one plug as it did I looked for the timing mark no were to be found at least not near the tdc pointer and the piston was near the top I can not get an exact tdc on the piston till I can get the truck on the lift and turn the flexplate back and forth till I get the highest point for the piston, but it is obviously not where it belongs.  So all indications are that the harmonic balance has slipped on the the crank pulley.  That is all I can come up with and I thank all of you for your help and suggestions and I will need to find the time to replace the damper pulley.  Thanks Ed

do it soon.
the outer ring can walk inward and make ugly noises when it contacts and rubs thru the timing cover.
the pulley will keep it from going the other way.

[Ed ke6bnl]

Well I spent some more time on the timing, the mechanical advance works and as you rev the motor you can see the timing mark move also the weights are free to move and return to the center, I removed the dist cap and rotor, I turned the engine over well my boy did and felt for compression stroke and for the rotor to point to the number one plug as it did I looked for the timing mark no were to be found at least not near the tdc pointer and the piston was near the top I can not get an exact tdc on the piston till I can get the truck on the lift and turn the flexplate back and forth till I get the highest point for the piston, but it is obviously not where it belongs.  So all indications are that the harmonic balance has slipped on the the crank pulley.  That is all I can come up with and I thank all of you for your help and suggestions and I will need to find the time to replace the damper pulley.  Thanks Ed

do it soon.
the outer ring can walk inward and make ugly noises when it contacts and rubs thru the timing cover.
the pulley will keep it from going the other way.

thanks for the advice there is no evidence of it moving or dislodged from its normal location, I had a jeep cherokee that right after changing the serpentine belt the belt was torn when I looked further I had notice that the pulley had moved to the point that it was not aligned with the other pulleys and shredded the belt, so I do know somewhat what you are saying thanks Ed

[Ed ke6bnl]

well I took the forums advice and I made a tool to find tdc in the number one cyl and on the compression stroke, turned the engine over with the flex plate till I found tdc and marked it on the harmonic balancer, I then had my boy fire up the engine and I put the timing light on and NO SIGN of the timing mark, that can't be right, turned motor off and my boy crawled under and said the mark is still there and while I was loooking I notice some shiny stuff behind the damper pulley, the pulley not only spun but had worked its way over to ride against the pulleys. The last time I wrote the damper was still in the original location all I did was drive it to the gas station to get the gas tanks filled.  When we removed the pulley the outer ring of the balancer just slid off.  We installed a new damper and seal and timed the truck and all is ok.  So I want to thank all of you that helped me throught this ordeal and all your usefull suggestions and we solved the problem about 6 days before I leave on my two week vacation feeling a little better about making it to the Sierras.