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I have the cylinder head and manifolds off my '32 900 series to do some valve work. Someone told me to replace the studs with new ones. Is this necessary? Recommended? I have about 8 of them out already but the others are pretty stubborn. Is this a waste of time? Thanks for your advice.
Allen

I've done plenty of valve jobs on these engines and don't routinely replace the cylinder head studs unless the threads have been damaged or if they had significant corrosion on them. If you had noticed that one or more showed signs of stretching (failure to hold torque) of course it should be replaced but that's extremely uncommon.

Clean the threads on both the studs and nuts before reinstalling the head, and leave them dry. Torque in a couple of increments to the final torque value; check and retorque as needed within an hour or so of running, and again after a few hours.

Thanks, Owen.
Our clubs resident adviser told me that to check cylinders for broken rings without removing the pistons, one way is to pour an equal amount of Marvel Mystery Oil into each cylinder and see how long it takes for the oil to drain through to the crankcase. Any that drain significantly faster than others probably have broken rings. I tried this and cylinder number two emptied in about a half hour, while all the others had drained very little in two hours.

Have you ever heard of this?

I am planning on dropping the pan and pulling number two piston and rod. Will the rod big end pass up through the cylinder?

Thanks so much for your help and advice.
Allen

Have you ever heard of this?

Yes, but never done it.

Will the rod big end pass up through the cylinder?

No. Turn the crankshaft so the counterweight is out of the way, then remove the rod bearing cap and push the piston and rod far enough up so the piston pin can be removed. Then piston out from the top, the connecting rod out from the bottom. When reinstalling if you will be using a new piston, pin and rod bushing you'll want to heat the piston in hot water first as the pin fit is a 160? F. push fit. For clumsy me it was a 3-man job; one under with the rod, one above with the piston pin, and one manning the stove, hot water and the piston placement. No doubt others have found an easier way.

If a ring has broken, I'd strongly suggest checking carefully the ring grooves for wear as that's often the reason for ring breakage. If worn they can be cut oversized and wider rings or rings + a space installed. Important to install the spacer above the ring in question.

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Thanks for this great information, Owen. Can you tell me what publication contains the pages you attached? I really would like to get a copy of it, if available.
Allen

Can you tell me what publication contains the pages you attached?

First image is from the Packard Service Letters; a reprint of selected snipets from the 7th thru 12th Series Packard Service Letters is available from PAC. If you can find them the full set of Service Letters for your specific year and model has more complete information. Second image is from Glenn's Auto Repair Manual which is among the best if not the very best book on automotive servicing, especially engine service and rebuilding. Long out of print but copies do surface from time to time.

I found a copy on Amazon pretty readily.

Two additions that have good info.

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Abe's Books appears to have used books of Glenn's for less than $5.00

Thanks again for your good advice. I have ordered Glen's Cyl Head and Engine Rebuilding and also the Sunnen book from Amazon. I have located the full text of the other Glen book on line.
I'm progressing along on the engine work. I measured the dimensions of all cylinder bores and was surprised to find that taper and out-of-round seem to be within five thousands of standard. Number two cylinder did not pass the Marvel Mystery Oil test. I'm dropping the lower crankcase and will pull that piston to see if there are broken rings. Should I pull them all and re-ring all the pistons?

Also pulling all valves to check condition of valves, seats and guides.
What am I missing?
Thanks again.
Allen