Ural Lubrication System

I've procrastinated long enough and finally took on the rear main bearing. I didn't have a socket the correct diameter to fit in the rear bearing carrier. But today I found an axle nut socket from a Jeep front axle in the toolbox and it fit perfectly. I didn't think it was heavy enough to get the bearing out but it came out with only a few taps from the dead blow plastic hammer. This bearing feels really rough and may have been the source of most of the bearing noise.

Sufficiently motivated, I took on the front main bearing retainer and tapped it out using a ½" extension and the dead blow hammer. Once it was out, I blew out all of the oil passages with compressed air to clear out any leftover solvent or metal chips. Thanks to a video just posted by Van Le, I knew were all of the passages were. There is still one broken screw in the front timing cover that I haven't been able to get out. I am thinking of looking for a small reverse drill bit to use.

Here are a couple of photos of the interior of the block. The upper one is from the bell housing through the opening that holds the rear main bearing carrier. One of the two small pipes (the right one) takes the flow from the oil pump out to the oil filter. After the filter, the oil flow splits to the front main bearing, the timing gear, the left cylinder and the other pipe to the rear main bearing. After the oil flows through the main bearings, it is caught by the slingers attached to the crank and oil is funneled into the big end rod bearings. After the oil goes through the rod bearings, it is splashed around the inside of the engine onto the cam lobes, rear cam bearing, the lifters and into the right cylinder and both wrist pins. Some of the oil that hits the lifters flows down along the push rods to lubricate the rocker arms in the head before draining back into the crankcase through small drain holes.

Most of this is a note to myself explaining the oil flow within the engine. The second picture is the view of the bottom of the engine with the oil pan removed. Full oil level is roughly at the bottom of the opening next to the oil pump mount. Those openings are how oil returns to the sump.

We are driving to Delta this afternoon to pick up the parts from Mickey! Assembly can begin...