Re: C engine?

Posted by HH56 On 2024/6/19 10:39:59

Quote:
There is a C used as a suffix to the engine number stamped on the block and that C indicates a different piston and ring combo was used in that engine from those spec'd or installed when the engine was introduced. If your engine number is not followed by the C the rings you found may not work. Here are the details of the C change. There may be other letters as suffixes used in combination with the C. There were other changes to those engines and here is a chart showing those major changes. The other suffixes usually had a service bulletin or article issued detailing what was different.

In addition to suffix letters, there may be symbols such as stars or hashmarks etc used before or after the engine number. Those often indicate a change somewhere else in the car that is different than what was originally built or spec'd. Trying to remember the meaning of a suffix, symbol, or varied colors of dabs of paint here and there must have truly tested the memory of a Packard mechanic.

As far as the low compression issue don't forget the valves. Rusty and sticking valve stems is a common problem after a long sit and those engines also needed a periodic valve grind as miles accumulated. Be very careful of the gas used while you try to start the engine. If you are using old stale gasoline that might have been in the tank or lines, a few minutes of engine running on that old deteriorated gas and additives deposits a substance on the valve stems. Turning the engine off and letting it cool down and sit for a time has been known to stick the valves so completely it took major disassembly and brute force to free them.