I apologize for starting a new thread to post this but I felt it important enough that everyone see this who may have never heard of this happening and if I buried it in my other post alot would miss it.......Mavrocket wins the Matchbox Maverick for the correct guess, do they make a hardened pin to go here, if so I want it. And I really appreciate all the support and offers of help I sincerely do, ya'll are a great bunch but I'm afraid, it's down to a money thing.....it's gonna be down awhile I'm afraid, I hope the heads can get away with just replacing the valves but as much shock as the whole system took, I can't see not replacing the rotating assy. and of course pushrods are bent which brings into question the rockers, etc. I have a feeling this motor is somehow going to end up a 347
What was bugging me so much was we had taken care when building the motor, had been driving it and even running it hard so I'm trying to think what could I (have done) to cause this, well now knowing what happened I admit I have never seen or heard of this on a fairly mild engine anyway......as I ask already what can be done to avoid this, hardened pin, multiple pins, etc.? Also for what it's worth the timing chain has about 1/2 inch slack, I don't recall it being that loose when installed, is that normal?
seeing that kind of thing break is always scary..... I'm sorry to hear about your motor. making it a stroker will definitely be making the best of a bad situation. and I'm not 100% on this but i don't think that pin is replaceable though. but i am not at all sure on that. i sincerely hope to see you up and running again!
Yeah a $0.50 pin sure caused a hell of alot of damage, thanks for the well wishes and we will be running again but it will be awhile......money And I may be the first but I might just see about drilling another pin hole in cam and gear for a two pin set up, I just can't believe such a weak link, especially one that can wipe out the whole motor..Damn
Was the bolt that holds the gear on, still tight? I did some searching, since I was interested in this, this is from Crane Cams: "The dowel pin or Woodruff key does not drive the cam; the torque of the timing gear bolt, or bolts, against the front of the cam drives the cam. Some reasons for the dowel pin or key failing are: Bolts not being torqued to correct specs; Incorrect bolts of a lower grade being used; Stretching and losing torque; Not using the correct hardened washer that may distort and cause torque of the bolt to change; LocTite not being used; Or some interference with the cam and lifters or connecting rods causing the cam to stop rotation"
"some interference with the cam and lifters or connecting rods causing the cam to stop rotation" that was my thinking...something else locked up and broke the pin. what does your...oil pump drive shaft... look like?
I agree with Dave, my first thought was the bolt not being tight that attaches the top sprocket to the cam..... I have seen this happen before.....
The ignition timing may have been really early and caused a shock in the rotating assembly strong enough to break the pin.
Ok this is an answer to all the above questions, the bolt was tight, it has the correct washer and Loc-tite was used....NOW since Mavrocket mentioned this it is possible since I had pulled the disty that I stabbed it wrong but don't think so but I would have never thought timing could do that and as for the other questions I am pulling the motor this evening and get into the bottom, I'll let ya'll know if I find anything else.
I feel bad for your loss, but you will get through this. I know it sucks for your kid, but maybe it's better it came apart now rather than while he was driving it.
