Packard Forum Index » Post-War (1946-54)

Well, they delivered my 49 Limo yesterday and after fighting the beast off the trailer she is now safely ensconsed in my friends pole building. Spent a few hours today unpacking boxes of parts and pieces and looking things over and am now having a severe case of "what the heck did I do" syndrome!! My best guess is that it does not have its original engine. I knew the head said "Thunderbolt" on it and it appears to have a casting date of 10-28-53 on it, i just thought someone had replaced the head at one time. But, on further examination, the engine number is stamped on a boss on the rear left corner of the engine block. Doing some homework on this site, that is not where they had the numbers on the 49 blocks. Also the engine number does not mesh with the numbers listed in the tables on the site. the engine number does match the number listed on the old title I got which was issued in Feb. 1969, so if the engine was swapped it was done a long time ago. There also appears to be a casting date on the block below the starter which indicates 12-18-53. My question is, are there any major differences between the 49 series engine and a 1953 model. This engine is a 327 CU inch engine so at least that is correct. Any input would be greatly appreciated, Thank you!
Kevin

Various heads were interchangeable and swapping heads was factory sanctioned as the way to change compression ratios. Just having a late head is not really indicative of the rest of the engine. The casting date on the lower engine just above the oil pan and not the head would let you know for sure when the engine was made.

Except for some added mounting bosses for the later engines, the basic engines are the same externally but in a 53 engine possible internal differences from the standard for a 49 could be main bearings and the valve lifters. 49 327 engines did not offer the 9 main and were usually solid lifters -- although hydraulics were an option on some models.

You will have to look at your engine number to determine how it might be equipped. If it was a 53 327 from another car, engine numbers starting L3 L4, or L6 would be expected and the chart will help you determine how it was equipped. If it was a service engine installed by a dealer I am not sure if the same numbering system was used on those to immediately tell how lifters were equipped. On unnumbered engines it would be easy to count the plugs in the oil gallery to determine the main bearings but you might have to visually check the lifters.

In addition to the just mentioned different method of engine mounting, another significant difference between the early and later 327 engines is the style of the waterpump which also gives a different fan location corresponding to a different radiator size and position. I don't know if the water pumps are actually interchangeable, though I suspect they may be. And the method of motor mounting can be swapped.

Hi everyone. I just wanted to post a quick update on my engine question. I decided to pull the front clip off to get better access to the engine and front suspension for cleaning and inspection. . After a better view and cleaning of the boss on the block I was able to make out the whole engine number, it was "M306451". a quick check of the engine number list shows that this engine is from a 1954 Clipper DeLuxe. I was a little disappointed that I don't have the original engine in my car, but it's still pretty much the same 327 engine and it has 10 horsepower more than the '49 version so I can live with it! What makes me feel a lot better about things is what I found when I pulled the head and valve covers- Nice new .030 oversize pistons and exhaust valves!! The valve bay was completely cleaned and primed and new valve springs installed! It looks like this engine has had a pretty major rebuild and it has been run very little, if at all. I don't know why they didn't replace the intake valves as well but it looks like there are new seats or at least they were reground. The engine is pretty stiff when turning over by hand. I can manage it with a two foot breaker bar on my ratchet, so I'm hoping the bearings are all new as well, but I haven't pulled the pan yet. The plan for right now is a lot of cleaning and getting a gasket set for the engine. Unfortunately whoever did the work on this engine used silicone in place of gaskets . they also painted the engine in Packard green instead of gray, so I'm on the fence as to repainting the engine in gray or just touching up the green.

I don't know why they didn't replace the intake valves as well

Intake valves have a much easier life than exhaust valves; it's fairly normal for one set of intakes (with a grind or two) to outlast exhaust valves by a wide margin. Ditto for the guides.