List:
I must rotate the two camshaft sprockets in order to install the remaining two setscrews in the sprockets. Although the starter is in place, both the intake and exhaust manifolds, as well as the alternator are sitting loose in the engine bay. The head is in place although the cam covers are not, , and the castle nuts on the had were used to torque the head studs to 54 lbs. I have yet to do a second round stud torquing, as I understand the studs do stretch.
Is there anything wrong with using a box wrench on the front of the crankshaft to turn over the engine and to get the sprockets in place for the setscrews?
Thanks
Lou
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Re-torquing is to be done after driving some 1000 miles, Lou - not as part of the installation process…
When retorquing; back off the nuts half a turn, the torque to spec value - one nut at a time in the prescribed torqueing sequence. Otherwise, the nuts bind - giving wrong torque readings…
And, of course, having moved the engine to place the sprockets; move it back to TDC and recheck valve timing…
Frank
xj6 85 Sov Europe (UK/NZ)
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Frank
xj6 85 Sov Europe (UK/NZ)
And it is possible that valve timing isn’t good anymore after you tightened the chain. No problem, just get it close on the second try.
Also, Lou, check the tolerances after installing the cams. They might have changed, we went back in to get things perfect!
You ideally use the nut on the pulley; I need a footlong bar to turn an engine.
David
Frank:
Thank you for the guidance. It does make sense to do the re-torque after some use. I would imagine that the heat of the engine as well as the pressures put on the head and block in normal operating could have an affect on the torque.
I will modify your suggestion and do the re-torque after a few hundred miles. I have owned the car since 1978 and thus far have only driven 5,000 miles. 
Regards
Lou
David:
Thanks for your suggestions. I’m afraid my brain is not firing on all six cylinders this morning. Could you clarify a few things for me.
Valve timing- My Autobooks repair manual says that the 4.2 liter engine, with Stromberg carburetors, fires at 5 degrees before top dead center. I usually set that by turning the distributor with the engine running until the ignition timing scale on the crankcase damper points to 5, which I have marked with some red nail polish. Is there a way to do that without the engine running?
Next, you suggest “checking the tolerance after installing the cams.” With four children and fifty years of marriage, I have learned the important of tolerance, and/or a large bottle of Jack Daniels. However, i’m afraid that I don’t understand that in an automotive context? Would you please elaborate.
Thanks
Lou
Might be your timing.
You don’t need to know when the engine fires (yet).
You needed to know where top dead center is - put a screwdriver in a spark plug hole of the frontmost cylinder, number 6. and carefully turn the engine until it peaks at the top. Now, verify that the markings on the crank damper align with the pointer at 0°.
Then you made sure both camshafts were at top dead center on the firing stroke. That is when both valves are closed and the cam lobes are pointing ‘up’ at the frontmost cylinder.
Next up you oriented the notches on the camshafts with the sheet metal stamped tool. They fit well enough, so you slid the sprockets on the camshafts and fastened them together.
With the camshafts in place and their rotation fixed to the crank, you can use the feeler gauges to make sure all valve clearances are to spec., because later you’ll have to remove the whole operation should one be out of range. Ideally, you can reassure yourself that things are okay.
Now, you must tighten the upper timing chain with this other tool we were talking about. When you have the chain snug, re-insert the stamped tool and check if both chains still line up in terms of cam timing. Don’t forget the securing nut and safety wire or tabs before you put on the valve covers (I only used sealant at the back).
As you verified your timing marks on the damper earlier, you’ll have no problems setting up the distributor later, when things are back together.
One trick to crudely check timing; with points you can align the distributor to the point at which the points open, but either re-check with the timing gun or drive it uphill in top gear and advance until the engine starts pinging and then back off a little bit.
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Do not(!) mix ign timing with valve timing setting, Lou…!
Valve timing is set with the engine at TDC - using the valve setting tool. What David stresses is to verify that the pointer and markings on the damper really points to ‘true’ TDC…
Frank
xj6 85 Sov Europe (UK/NZ)
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Frank:
Thanks for clarifying that, I assumed that was what David was getting at, but I am not experienced enough with the relationship between the position of the valves and the TDC markings to visualize how they are related. Your comments help.
Thanks
Lou
C3993 (the setting tool) and TDC #6 (with whatever you have, a screwdriver or rod,…) take care of valve timing. The problem with the damper is that the bond between the rubber and the steel can fail, and then the markings are no longer trustworthy.
