The Stovebolt Site Forums The Shop Area Engine Shop Not enough oil in 261

Hey guys, so I'm getting back into trying to get the 261 in my '55 6500 running. But one issue has me scratching my head, when I drained the old oil, I only got 4 qts out of the engine, even though the dipstick read full. I know the proper amount should be 5 qts.

The engine has a '59 block, and the prefix code on the block ends with "L" (6000 series truck engine).

Could it have been re-assembled with different parts? I did some browsing through the forums here and decided to take some measurements:

Dipstick (take these with a grain of salt) from cap to end - 15 11/16", from cap to FULL line - 13 29/32"
Dipstick tube - 7 1/8"
Oil pan, mounting flange to plug (measured from outside) - 8" deep

Any help would be appreciated

There are so many possible combinations of oil pans, dipsticks, and dipstick tubes that it's hard to say what's right. As long as the crankshaft and connecting rods don't dip down into the oil sump and whip the oil into foam at highway speed, adding another quart above the "full" mark probably won't hurt anything if it makes you feel better. The only way to be sure of the oil quantity matching the dipstick mark would be to pull the oil pan, measure the depth of the pan and the dipstick, and see how close to the crankshaft the level would be with 4, and then 5 quarts in the pan. Then mark the dipstick accordingly.

A bypass oil filter will add one quart to the capacity, and only about half a quart will drain back into the oil pan within about an hour after the engine stops.
Jerry

When was the last time the oil pan was off? You could have a quart of sludge adhering to the oil pan. I had that happen on a new-to-me 216.
The view of the oil pan from above looked like a satellite view of the Amazon river. I wish I had taken a picture.

Very good point Jerry, honestly it doesn't matter to me how much oil is in it, I was just worried that there wouldn't be enough. Once I pull the pan I'll take the measurements and go from there!

52Carl - Probably before I was born! Supposedly the trucks been sitting since the 80s. The old oil was a little sludgy when I got down to the last bit when draining.


I originally wanted to get the engine running, then pull it....but I'm tempted to go vice versa now.