I'm looking for a way to preoil a flatty before a fire up. I have a motor that has been setting for many years and would like to get some oil in there before I fire it. I have heard of guys hooking up external devices through the oil port in the rear of the block but I've never actually seen one. In the past, I've popped the rod and main caps and did the STP thing. I'd rather keep this one unmolested. I'm thinking of rigging a Chevy oil pump to this port and just letting the oil run out the plug in pan into a scavenge pan to be recirculated through the rear port. I believe this will run oil through everything except the rear main, (?). I'll drive the pump with my cordless drill. I've tried the search and can't come up with anything. Also my engine is a '48ab if that matters, which it shouldn't.
Years ago the machinist at the local parts store used an old pressure bleeder tank for a pre-oiler. Dumped 5 qts. of oil in the bleeder tank which was connected to the engine with an oil fitting on the block and a shut off valve, pressurized the tank to 40 psi, opened the valve and instant oil pressure at start up. I made one for my 8ba start up from an old paint pot. For some reason didn't work as well as the brake bleeder set up but it got the job done. I've also heard of using a hand pump garden sprayer to achieve the same results.
I too have done filling through the pressure port, once, many years ago. I just set up a funnel and let it drain slowly through on it's own (overnight I think). Not sure if I did a full fill or just a couple quarts worth. I did not hook any sort of pump to it.
Why not just pull the plugs, squirt some oil down each one and crank it for a moment? Low speed and zero load, so the bearings etc. don't need much lubrication for the time it takes for oil to go everywhere.
The bearings are what needs the oil, particularly the rods on a full floating motor. If I'm correct, I should be able to pressurize the crank from the rear port. I'm not sure if I will lose most of it through the flattys oil pump though.
I'm using a 1 gallon garden sprayer with the wand modified to first go through an oil filter, and then into the back of the block or remote filter. I pump it up to about 15 (engine) psi and push 1 quart or so of oil into the engine. This takes a few minutes, so you have time to rotate the crank a couple of times to ensure good circulation.
All good comments here. I'm going to make a pressure vessel with about two quarts. Let you know how I make out here.
I used an old oil pump and plumbed it into the rear oil galley and used my electric drill. Pumped about 2 gallon of oil throughout the whole engine. Worked great! Walter
Cleaned it up a bit, not much. Looks damn nice on the bottom end. Just a little attention on the valves and we'll see what she sounds like,.