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It's amazing that my 32 ran well despite a shoddy rebuild. Today I found this out from the engine rebuilder. The balancing weights bolts were only securing them by about 4 threads instead of 2 inches. Luckily one didn't break loose and sent it flying through the crankcase. Even though the rebuilder had epoxied and welded the bolts, one weight still was a little loose. Hopefully it will be done right this time.

What is the size and threads per inch of the bolts????

The normal engineering rule of thumb is the diameter of the bolt x 1.5 or simply put, one and a half times the diameter of the fastener.

You may want to call Art Brummer Packard Parts @ 207-743-5001.
They were making the correct bolts to secure the counter weights on the '32 crank. The P/N for these was P111.

If they do not carry these anymore, use a grade 8 socket head cap bolt and tack weld the head of the bolt to the weight to make sure it doesn't loosen up. The head of the bolt may have to be turned down to fit into the c'bore on the crank weight. A little Locktite 271 on the bolt threads would be an added safety measure. Do this after the bolts are torqued down.

I recall there was approx. 1-1.5 inches of thread engagement of these bolts into the crank.

The counter weights on the '32 overhang the rod journals. so if the crank needs to be ground all the weights on the crank usually need to be removed before grinding the journals.

Bottom line - you don't want these coming loose!

Good luck,

Dave

Dave,

Thnaks for the tips on the bolts. This isn't the first Packard engine they have done so I expect it will be done right. It's amazing that they were only secured by 4 threads. And after the previous guy had used epoxy and welded them, one weight you could move with your hand. Hopefully all things bad done to the engine on the previous rebuild will be corrected.

I'm still anxious to see how it performs after a correct rebuild has been done.

One addition comment that may be helpful when having the engine rebuilt:

I had a reputable engine builder bore & pour the major stuff so I could finish the job and save some $$$$. The engine builder looked at the camshaft. They polished the cam lobes, no wear was evident thanks to the roller rockers.

I finished assembling the engine and couldn't get it to run right. I finally ended up measuring the cam lift per lobe as I rotated the cam because of difficulty adjusting to .006 clearance.

I discovered a few of the cam lobes were not located on the center axis of the camshaft. Even though the cam lobes looked perfect, because they were bent off center it was impossible to adjust to .006 tappet clearance. As I rotated the cam I was getting some valve lift even when I wasn't on the cam lobe.

This required I pull the block off the crankcase and remove the cam, which was sent out for straightening and re-grinding.

Lesson learned - DO NOT let any machine shop tell you your cam is OK just because they don't see or measure wear on the cam lobes.

Lift for each lobe can be determined by measuring the base circle of each lobe and subtracting it from the overall lobe height.

The lift per lobe on my cam was within .002, but since some of the lobes were off center .011, it was impossible to adjust to .006 tappet clearance.

If you're not having your camshaft re-ground ask your engine re-builder to inspect the cam and give you base circle and lift measurements for each lobe with the cam set on vee-blocks and rotated on it's journal's.

This is the only way you will know each lobe has the correct lift and is positioned correctly to the center of the camshaft journal bearings.

Dave

Dave,

Well I guess I had the good fortune to have a seized roller on the lifter which create dthe need for the cam to be reground.