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I have the 48 custom eight. But my question is can you pull the oil pan off with out pulling the motor. I would love to replace the rings but don't really want to pull the engine. And since I am ok and small stuff and I know that there are many that have great advice I would love to hear from you.
Thank
J

Sure, I re-ringed by 48 Custom 8 years back with the engine in the car. The forward pan bolts are pretty close to the cross member and even with small hands you may have to jack the front of the motor up a bit to get access. You may also have to rotate the crankshaft after the pan is loose to rotate the counterweights to a position that allows the pan to be withdrawn.

You'll of course have to hone the cylinder walls and there is considerable risk, if you don't take elegant precautions, of getting the grit into the engine. So super cleanliness during and after honing is essential. Also might be a good time to take a close look at the rod bearings and wrist pins, assuming you'll be reusing the old pistons. If so, perhaps you should read up on piston ring groove wear, resizing, ring spacers and possibly expanders, etc.

When I did my Custom 8, I cut the ridge, honed the cylinders, replaced the pistons with new, replaced rod, main and cam bearings, all with the engine in the car. It's still happily purring along to this day.

Maybe a bit more detail on the above job will be helpful. The engine had perhaps 100,000 miles on it and was burning a bit of oil, a quart every 400-500 miles or so. But what forced the issue, and something all flathead owners should note, was that when removing the spark plugs for cleaning a pebble that was in the spark plug well but not seen fell into the cylinder and efforts to remove it failed. The lesson - when changing plugs on these engines ALWAYS use an air gun to blow the plug wells clear before removing the plugs!! Cylinder wall taper was about 0.004 inch, within reasonable range for replacement with new standard pistons and rings. No appreciable crank wear, standard size main and rod bearings fitted.

"...when changing plugs on these engines ALWAYS use an air gun to blow the plug wells clear before removing the plugs..."

That's the best advice on tune up procedures ever given. I'll second it for ANY engine flat head or otherwise. A highest tune up precaution priority that i forget to do from time to time.

PackardV8, thanks for the nice words! Back when I had that Custom 8 I was young and poor, barely had two dimes to rub together and didn't relish having to buy a head gasket; after failing to get the pebble out, I took a chance and started the engine, hoping it blow out past the exhaust valve. Of course it didn't, it was on the top of the piston where there is no clearance to the head and it blew a hole in the piston and blew the oil filler cap into the yard next door (good thing the hood was open). Not that the engine didn't need some work anyway - but lessons learned that way are not easily forgotten.

I performed a driveway overhaul on our 49 with the 288 years ago. One of the pistons had broken between the rings. I ordered one replacement and while waiting for the new piston I reassembled the rest of the engine. I was very careful to put all parts back the way they came apart. (#1 piston-#1 cylinder; #3rod cap- #3rod etc.) When I received the new piston for #2 cylinder which just happened to be directly above the cross frame and difficult to access, I installed the piston and rod assembly from the top and tried unsucessfully for about 1 hour to fit the rod cap on the rod. I took the #2 piston and rod out of the engine and tried again to install the rod cap. This was attempted on the work bench unsucessfully. While waiting 2 weeks for the new piston the rod journal had expanded enough that the rod cap would not go on. A local machine shop refit the rod and cap. We have logged over 100,000 miles since with no problems. I would advise that if your engine will be apart for any length of time to place the rod caps on the rods while stored.

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How is this even possible? I've had rods apart for years and never had this problem.