Re: 6th Series Bearings

Posted by Jim On 2009/12/27 2:02:04

Converting to inserts is a very complex process. There is a lot of machining involved. I converted mine about 2 years ago. I did not convert because of fear about babbited rods, but because my factory inserts had been re-babbited at some point, and were suffering from massive failure. My personal research and discussions with very knowledgeable individuals led me to the conversion to modern inserts. I agree with O-D on the blobs of brass being filed not sounding all that good. Mine were welded full circle and machined to size for factory specified connecting rod side clearance. This ensures the rod will not knock from excess side play, and also ensures the proper amount of oil can push past the side clearance to stay cool by allowing new oil to enter the clearance, yet ensure enough oil remains in the working clearance of the rod to maintain an adequate lubrication boundary layer.

Many people involved with Packards said this was a tried and true method. Some thought I should have just converted to babbit. One fellow who has had about 20, maybe 30 different user accounts on this, and the AACA site gave me no end of grief, basically predicting doom and apocalyptic failure. The car presently runs fine.

At the time, these were my only options because the bearings had not been available for years. At present time, to the good fortune of 320 owners, David Schumacher had these bearings reproduced. Had that been an option when my situation arose, I am almost sure I would have used those bearings due to the intense amount of work in converting.

Many, including O-D, Tbirdman and others here that obviously put responsibly driven miles on their cars report little issue with babbited rods. In the end, you will have to gather the opinions of those who have had experience in this area and decide.

The one thing that is very surprising to me is how common this question / situation seems to be. I am very surprised how little is really known about what bearings interchange, and who is tooled up to do the conversion. It always seems like a new and unexplored frontier (with the exception of some known info such as the article O-D has mentioned).

I will follow your thread with interest, as I am interested to see what innovative fixes fellow Packard owners might employ in order to stay on the road.

Best of luck,
Jim