Hey guys,
I am just in the process of rebuilding a 1z which Ill be using to swap a AAZ motor currently in my 1988 Toyota truck. Anyways, last night I tried to install the camshaft and followed the FSM procedure (lightly alternating between cap 2 and 4 with cam and crank at TDC)
Well while tightening the cam I heard a crack, sure enough cam cap 4 is cracked, cam cap 2 looks warped and there are hairline cracks where the cam cap studs go into the head. Yikes. This really sucks as the head was rebuilt and I have heard of others having this issue (obviously user error)
So what are my option? Should I rob a cam cap from a different motor and just try to run it as is? I figure there are still 3 other caps holding the cam in place, what is the worst that could happen?
Or should I remove the head and try to weld up the cracks?
Perhaps buying a an unloaded china head and transferring all my internals into it would be a better option?
Also whats the trick to getting these cams in with no damage to the head?
Thanks a ton for any suggestions.
The caps are matched to the head. You'll need to find a machine shop to help you or another head. Swapping everything to a bare China head is viable.
Do you want it right or hillbilly style? If you have a good casting I would take it to a machine shop where they can take a little off the seat of anther cap and line bore it to match.
last night I tried to install the camshaft and followed the FSM procedure (lightly alternating between cap 2 and 4 with cam and crank at TDC)
Well while tightening the cam I heard a crack, sure enough cam cap 4 is cracked, cam cap 2 looks warped and there are hairline cracks where the cam cap studs go into the head. Yikes.
Either the cam or the crank was not at TDC while you were tightening it down or the valve setup is wrong. If you have the cam oriented correctly (camlock in) and the crank at TDC, you will *not* get piston/valve contact while tightening the cam. Regardless, I always rotate the crank CCW from TDC a few degrees in order to be safe.
As others have said, get a couple caps, get the cam line bored.
The real point that everyone missed it that you NEVER install a cam on one of these with the motor at TDC. I don't care what anyone says, ALWAYS roll the motor a little off TDC when installing he cam. (Or the head with the cam in it.) You can roll it back AFTER the cam is installed. This prevents any kind of damage.
FWIW: You need to be more careful when assembling things. You would have to have tightened the cap nuts long after it was obvious that there was a problem.
thats why i mark the pulley, and turn it back a 1/4 turn; just as easy you could have had cam, what is it, 180dg out and at cam #4 tdc, looks like #1tdc if you use the timing slot to determine is your at #1.
The real point that everyone missed it that you NEVER install a cam on one of these with the motor at TDC. I don't care what anyone says, ALWAYS roll the motor a little off TDC when installing he cam. (Or the head with the cam in it.) You can roll it back AFTER the cam is installed. This prevents any kind of damage.
FWIW: You need to be more careful when assembling things. You would have to have tightened the cap nuts long after it was obvious that there was a problem.
Bah... There's no issue with the crank being at TDC as long as you have the cam lock in the end of the cam. There's nothing wrong with rolling off TDC either, but if you can't get inserting the cam lock correct, you're hopeless and shouldn't work on engines, ever.
As others have said, get a couple caps, get the cam line bored.
I should have also mentioned to identify which valves got mashed and replace those as well.