56 265 oiling system

[tkrphxr]

I need some info on the oiling system. I have a friend building the engine for his 56 and is having a problem with the oil system. I understand from him that this is what is called a late 56 265 block. The first time they put the engine in they could get no oil to the lifters or the cam bearings. I have been told that on this particular engine the rear cam bearing is supposed to have three oil holes in it and I have looked at the block and you can see three distinct oil galleries. There is on for each side for the lifter galleries and one in the middle for the cam bearings. I was also told that the rear cam journal is supposed to have a grove around it to let the oil pass from the block throught the bearing to the Lifter galleries. The machine shop insist that the cam bearing is only required to have two hole. Can any one please help me. I hate to see them put this engine in and have more problems. Please please help Thanks in advance Charlie

 

[JohnZ]

265's take a special wide rear cam bearing with two oil holes in it, that line up with two oil holes in the block; the later (narrower) cam bearing can be used instead, but it only has one hole in it, which must be filed into a 1/2"-long fore-aft slot (1/4" forward of the center of the hole, and 1/4" rearward of the center of the hole). In either case, the holes/slot in the bearing must be aligned perfectly with the oil holes in the block when it's installed.

The other half of this 265 oiling issue is the camshaft rear journal - it has a flat milled across it (not a groove around it), which allows the two oil holes in the bearing to communicate once each cam revolution to get oil to the lifter galleries.

If you don't have the correct (or modified) rear cam bearing AND the flat on the rear cam journal, you won't get any oil to the lifters. This all changed for 1957, using the conventional one-hole bearing and plain cam journal.

 

[Tom Bryant]

Hi Charlie,

Here is a picture of a 1956 265 cam rear journal. You can see the flat milled into the journal that connects the 2 oil holes as John has discribed. This particular cam is a 240 horsepower 1st design sevice package cam that preceeded the famous "097" Duntov. Any cam you use in a 265 must have this flat. It can be milled into newer cams with no problem.

Tom

 

[JohnZ]

I should also have mentioned that the distributor housing configuration (just below the hold-down clamp flange) is unique to the '56, and includes a cast-in groove which forms an oil passage to the lifter galleries; use of a later distributor without this partial groove configuration will also result in a major internal oil leak and low oil pressure.

 

[old-hot-rodder]

One more thing! If your distributor is installed "not" in the exact position as original the oil can't come up the shaft. I was off one tooth and even though the wires were in the correct order the dist. was off one tooth and NO OIL!
Al Whittier