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Hey joeyearl,
All I can figure is I have them in the wrong spot. But, when I compared new to old, that is how it looks like it should go. The rear cylinders appear larger in size next to the front. I'm not sure if there would be any harm done in putting larger wheel cylinders up front, and smaller in back. I just know when it comes to brakes, you better get it right before you get out on the road.

GearRat52,

The larger cylinders should always be at the front.

My '48 had adapters on the original rear cylinders- the adapters are the same size, but went from a flare (brake line) to a deep fitting with a copper gasket at the cylinder. My new rear cylinders that I sourced from NAPA ($8 each) took similar adapters, but used a flare connection on both male and female and stepped down one size. See photo. The fronts changed from the flare fitting (hose) to the adapter which went from a flare (hose side) to the deep 3/16" with a copper gasket. See photo.

My car originally had 1-1/16" fronts and 15/16" rears- the new ones from NAPA are 1' rears and 1-1'8" fronts. That shouldn't matter. But the larger ones are always at the front.

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Hey thanks,
I was talking about the length of the body of my wheel cylinders. I hadn't checked the bore, but I'm pretty sure I have it backwards. The fittings don't make sense to me in the position they are in now. But, reversed it makes plenty of sense. The only thing that threw me off was the length of the rear compared to the front. That is why I put them in that orientation. Once the weather clears up here, I will switch the wheel cylinders around. It also didn't make sense to me that the rear would be larger than the front, as the front takes all the abuse. I'll try to get some photos too.

-Garrett

The rears may look longer because the diameter is less. Pop off a rubber cup and check the bore size to be sure.

Hey Joeyearl,
Man! I can't believe myself. I don't know how I could overlook something like that. I'm glad I had a hard time finding those fittings, or I'd be driving it around like that. Once off, I compared the bore sizes, and realized I had them backwards. I want to thank you, and Ross for pointing that out to me. It was a big time rookie mistake! I'll definitely check everything over several times before I get out on the road.

-Garrett

Hey Garrett,

Glad it worked out for you. I know you and I will both be happy to get our cars on the road! It will be the first time for me, driving a Packard, and I can't wait.

My master cylinder should arrive tomorrow, and I ordered a water pump rebuild kit today from Max. I may make a short test drive with the water pump leak if I get the brakes finished before the pump kit gets here.

I also ordered a one piece oil pan gasket from packardp@aol.com, as per BigKev's suggestion. Spoke with Phil (packardp) on the phone, and he tells me he makes them to order. Nobody else sells a one piece gasket. This guy drives a '51, so he's familiar with the L-8.

Tonight I put a quart of diesel fuel in the oil, ran it at idle enough to warm it up, and drained the oil. Maybe that will kick start the cleaning process. I don't look forward to pulling the pan, but I'm kind of excited about getting it all cleaned out. Mine has a big dent in the bottom, and I'll fix that once I get it off.

Yeah, I am chompin' at the bit to get this car out on the road. This is my first Packard, and first car. I started getting to work on it back in October, when nothing on the car worked. I've come quite aways with it; and by no means is it a showcar. I have really tried to focus on functionality with this car, trying to stay within some sort of budget. As for the oil pan gasket, I did mine a few months ago. It took a couple of days to complete, and there was plenty of sludge in the pan. I'll list the link below, so you can check it out. And, it sounds like we may end up getting these things out on the road close to the same time.

https://packardinfo.com/xoops/html/modules/newbb/viewtopic.php?topic_id=8586&forum=2&post_id=92279#forumpost92279

Just doing a bit of math on your new wheel cylinder diameters. The areas in square inches are:

15/16 = .6903
1 = 0.7854
1-1/16 = .8868
1-1/8 = .9940

Assuming I did my math correctly, these differences are about 12-14%. Though I doubt you'll have any problems with these larger cylinders, you may experience some differences from the stock diameters. Since the cylinder volumes are larger, it will take a longer stroke of the master cylinder to move the shoes the same distance, and it will take more pedal pressure to achieve the same force on the shoes.

I'd be interested in hearing of your evaluation after you get some road miles.

Does that mean I'm going to have to do some right leg strengthening exercises?

Actually, never having driven a Packard with brakes before, (or any Packard for that matter), I won't be able to make an educated comparison. I just hope she stops!

Owen,

So that means... if I can find some smaller than stock cylinders, the stroke distance will be shortened, and less pedal effort will be required?

I'm not too hydraulitically edumacated, but it would seem to me that if I had to perform a longer stroke action, the effort would be reduced on the stroker (my leg), resulting in more pressure on the strokee (brake shoes). Kinda like adjusting a fulcrum?

Just thinking.

J