VCCA Home Forums TECHNICAL - 1945 AND NEWER 1949-1954 Oil Filter how does it operate

I am cleaning up the engine compartment in my 53. I was looking at the oil filter and wonder how it works. Along the pipe that comes up the center of the filter is a small hole maybe 1/16 in size about 1.5 to 2 inches from the top of the pipe. Is that the only exit path that the oil must follow?

The incoming oil is taken from the main oil gallery (lower side of engine-left) and pumped into the (side) of the filter. This builds up pressure in the filter causing the oil to pass through the filter element and returns to the oil pan via the little hole in the center tube.. If you were to remove the return hose on the bottom and run the engine you would be amazed how much oil would be coming out, especially with the full pressure oiling of your 1953 235 engine.
The filter is rated as being able to filter 20 gallons of oil per hour.(from Chevrolet literature).
This is called a by-pass filter because just some of the oil passes through it. Some think it is not worth while as in a modern engine all the (hot) oil passes through the full flow filter.
Years ago when your 1953 was new the filter change was recomended every 6000 miles. Oil was usually changed every 1000 or 2000 miles back then. At 6000 miles it was common to find a couple inches of sludge on the bottom of the filter can along with what was trapped in the filter element - so they do work. In the manner most of our old cars are driven it would probably take 10,000 miles or more to see any acculation of sludge in the bottom of the filter.

Thanks for the information. I thought something like that was occurring but I am surprised to see that the hole in the center tube is so small.

If it were too large it would steal too much oil pressure from the main oil gallery......especially on the low pressure dipper engines.

Gene you wrote:

"If you were to remove the return hose on the bottom and run the engine you would be amazed how much oil would be coming out, especially with the full pressure oiling of your 1953 235 engine."

My questions:

a. How does it "build up" pressure. I thought the pressure to the filter was constant and rerouted if not flowing to the filter and, thus, not capable of being accumulated. How high a pressure would it accumulate to? Please explain.

b. Although 53 235 had full pressure oiling, I didn't think that included pressure TO THE FILTER as in say a 261. What about that?

c. 6k miles for a recommended change of filter says a heap about the efficiency of that trickle pressure filtering system. Doesn't it? Why even bother having it on there in the way if that's oil changes make it just another quart of oil to buy.

d. Was the 53 a babbitt engine?

e. Did the 53 have the oil distribution valve cover on the lower left side?

Thanks,

Charlie

I just wrote a reply and it all disappeared.....will do it again later.

There is oil pressure to the inlet hose when the engine is running. The oil is being forced into the filter under pressure (what ever pressure shown on the oil gauge). The oil is forced under pressure into the filter and exits through the small center return hole. It drains back into the oil pan from there.

The oiling system on a 1954 -1958 261 is the same as a 1953 PG or any later 235 engine.
In 1959 the oiling system was slightly redesigned on the 261 engine so the main feed was routed through a full flow oil filter, externally mounted with large lines. The filtered oil was then passed through the main oil gallery.

The US 235 engine for the Power Glide cars had the full pressure and drilled crankshaft and rod inserts.
The stick shaft cars and all trucks had the low pressure oiling, rod dippers and babbitt directly on the conn. rod. The person that made the original post is from Canada. ALL 1953 Canadian engines had full prsssure oiling.
Full pressure oiling should not be confused with a full flow oil filter.

The old by-pass filter passes 20 gallons of oil per hour. So in an hours time at least 90% of the oil passes through the filter and gets filtered in that hour.. Dirt takes a lot longer than that to accumulate. The amount of dirt found in a bypass filter under normal service is proof that it "works".


The 1953 dipper engines (216 qnd 235) had the metal plate. The US Power Glide and Canadian engines and later did not as they had the full presasure engine oiling. The full pressure oiling engines had full pressure to all points but was metered to the rocker arms where as the low pressure engines had high direct pressure to the main bearings only and low pressure to the other open ended oil lines. If the lines would have had the high pressure it would have robbed all the pressure from the main bearings. The oil pressure regulator (divider) was under the plate.

I think I answered all your questions but probably not in proper order.

Excellent information Chev Nut, thanks.

Thanks Gene.

I just can't seem to get it straight about the 53 235 PG engine and how to identify it. I had a chance to buy a complete 53 235 engine a couple years ago for a hundred bucks but turned it down owing to the oil distribution plate on the left side. I thought that because of that it would not be a full pressure engine as in the 54. I hope I didn't make a mistake. I think it came out of a 53 Bel-Air he was restoring but may have opted for a different engine. I don't remember if it was a PG 53 or not.

I guess that the 53 235 PG engine was just like the 54 235 engine and hard to tell the difference physically, so to speak.

Thanks again,
Charlie

The 1953 Power Glide block and all 1954 blocks will look the same. There are some internal changes in the "interior" of the 1954 blocks.
The 1953 stick shift block will have the tin plate because it has splash oiling..
If the block has the original head the 1953 will have the old style two center stud valve cover and the 1954 block will have the for screw valve cover.