I have been doing the header/cam thing and need some advice doing the reinstall. I read old threads here about placing the motor at tdc before removing balancer, hub, ect, and to the best of my knowledge I am ok to put the new cam in.

Can you guys look at the few pics I took with my camera during teardown to see if I have everything postioned right. (cam pin, hub, gears, ect) ?? http://community.webshots.com/user/poormanz28

I tried to feel for the #1 piston with a pen in the plug hole and believe I felt it. BTW, I am also doing rocker arms. One thing I didn't do was mark the hub and the crank before removing the hub. I didn't know it was not keyed. This is a concern now because my hub and balancer both have drillouts on them. I can get it on to were it is close but I do not know were perfect is. I think I can use the crank gear dot to line the hub up. I would hate to have a shakey motor. Still uneasily about getting it back together correctly.

Thanks for the help AGAIN
Jeff Dobbins

 

The timing marks on the crank gear and the cam gear should face each other at #1 TDC. If you have the timing cover off, line up the marks, and put it together. When you put the crank hub on, make sure the arrow is up.

FYI - I'm nearly positive that the balancer isn't keyed because it doesn't really matter how it goes on the crank. It is actually a vibration dampner, not a balancer. A dampner is not wieghted in any specific way to balance the motor.

 

I forgot to mark mine when I removed it but I was able to see where it was aligned by the mark left on the hub from the key indentation in the crank. I got it as close as I could see but I read that it isn't really important since the hub is neutrally balanced. When installing the crank gear if you used a timing set that only has one setting for the gear like the stock one does all you have to do is install the gear and turn the crank so the dot is at the 12 oclock position then instal the cam gear (which will only go on one way) and align it along with the chain so that dot is at 6 oclock. They should both be exactly oposite from each other. I had to do it a couple times to get it exactly right, you'll see what I mean, had to play with just the cam gear to get it exact. If you had it aligned like this before you removed it you shouldnt have to turn the crank again obviously. I used this guide when doing mine recently, it was pretty complete. Cam is done and running great! Good luck

 

Maybe a bit late but I'd recommend calling Thunder Racing and ordering one of their keyed crank hubs. Made my life easier and is extra piece of mind as well.

 

Thanks for the reply guys. Because the hub is not keyed I wouldn't think it would matter either. If the pulley is drilled out just to balance its own rotation then it really wouldn't matter how it went on. I posted a pic of my hub and pulley below. Both have drill holes in them of various deeps that I was assuming are for balance with the crank. If this is true then it would seem then that it would be important to get it on exactly how it came off, if the pulley and hub were drilled out for rotational balance that is.
Anyone know for sure??

http://photos.yahoo.com/jeffdobbins2000

Jeff Dobbins

 

Just get it as close as you can. If you want a for sure thing get a keyed hub. I had mine off / on many of times and got close to where the key way and the mark on the hub. I don't have any strange vibrations at all.

As for installing the crank / cam just line up the dot's to dot's on the crank and cam.

FYI the dot to dot method lines up #6 as TDC. You must still find TDC for #1 before you start to do your valve lash setting. When I did it in the car I used a pencil or something in the plug hole to determine when I'm at TDC. (Kind of crud but it works)

 

Oh great. I thought the dot to dot with the cam pin at 3 o'clock was TDC on #1. Thanks, I'm glad someone told me this. I did a search and found out that it is 12 and 12 for tdc#1 and not 6 and 12 which is tdc #6. This was answered by Shoebox in another thread so I fell pretty good about it.
Thanks

Jeff Dobbins