human-potato_hybrid

It broke trying to remove it to do this exact test 😂😭 and yes I have removed piston rings before but this one "got me". 2nd compression ring. I do need to remove all the rings anyway in the process of de-gunkifying this engine. Pistons look good; I measured one and the skirt is 3 thou below nominal; they are 1-1.5 below when new. I really doubt they are almost new. Though the ridges on this engine were already reamed, so who knows. New set is only like $150 from Egge so it's not the end of the world to buy a new set. Also I noticed cylinder #2 looks a bit off. It doesn't feel as bad as it looks and I had no more trouble pulling the piston out than on the others. But I think honing all the cylinders could be beneficial.

Ok so I have 1 broken piston ring. Does anyone hone / replace for just one cylinder or do you need to do all cylinders?

Update: I measured the #1 main and #3 rod bearings, and the clearances are 2.2 and 1.7 thou, respectively. The spec is 0.5 to 2.5. So we're good to go there.

Yeah Plymouth had a very interesting and detailed logo back in the day.

Saw this for sale recently. Owner said "ran when parked" and it hadn't been sitting that long. Seriously.

Well said. I am well-acquainted with some people who literally have no discernable hobbies besides drinking, drinking at the bar, and watching a certain fairly biased news channel. Then they wonder why I'm not "in touch with current events" because I don't spend 20 hours a week watching programming specifically designed to get me mad and addicted to the drama that is politics at a national level. Obviously these people are neither happy nor healthy; though there are certainly worse vices to be addicted to (like gambling), it's unfortunately hard to get these people to change in the slightest towards healthier behaviors when this is what they have done for years. What can be additionally frustrating is that these male Baby Boomers that I am referring to are, without a doubt, the generation and sex on average most interested in old cars of anyone around, yet my hobby of 50's Packards does not seem to hardly interest them in the slightest. And my stories are only slightly long and boring. 😉 Hope this isn't too personal or off topic but your comment (well, the reverse of it) rang as really on the nose for some of the people in my circle. ☹

@kgreen That's still only about 0.13 cu ft. so assuming it takes a typical amount of time to operate, I don't see it being any worse than vacuum wipers. I would check that the piston seal itself is not leaking. If you have the piston out of the car, depress the piston nearly all the way and plug the depressed side. You should be able to pull the piston away some and it should spring back. If it loses "springiness" quickly then it is leaking.

The main problem was the oil pump being so high made air get sucked in from the driveshaft. There was also no weep hole to lubricate the driveshaft from the pressure feed. A number of retrofits etc. have been made to these over the years to combat this issue, with varying degrees of success.

Yeah, the 55 Packards I have from the factory came with an auxiliary pump mounted under the oil pump. Other cars, and the same engines used on Hudson and Nash, used an auxiliary pump combined with the fuel pump. I have heard that the engines (320/352) are big enough that wipers etc. will still work fine without the auxiliary pump, but I plan on adding mine back anyway.

Now that you mention it, why does running lean make the engine run hotter?

Good point. A 1949 carb manual gives this blurb.

Thanks @joe_padavano. So my understanding about the device operation was correct, it's just that the air volume is small enough that the engine doesn't really notice/care about it. The pressure difference at idle is only like 5 PSI as I understand (30 inHg atmosphere -> 20 inHg manifold absolute pressure) so it's understandable that 5PSI times the volume of a wiper motor or brake booster is really not that much air. As a point of comparison, a 350 ci engine idling at 400 RPM will pull in its displacement once per 2 rotations, so it sucks in about 40 CFM, or 27 NCFM.

If you give me ID, OD, and thickness I can find a replacement seal.

Yeah felt seals are garbage. Even say in the 50's they had these felt seal + single lip seals; single lip for grease retention and felt to keep out the dirt. These can be replaced with a single modern seal. Example modern seal. Called an auxiliary lip seal or something https://www.skf.com/my/products/industrial-seals/power-transmission-seals/radial-shaft-seals/productid-20059

I know, but the vacuum port on the carb goes to below the throttle plates. So that's after the carb.