Oil bypass routing

Welcome to the Pierce-Arrow Society Forums Engine Oil bypass routing

Viewing 10 posts - 1 through 10 (of 10 total)
  • Author
  • #427307

    Does anyone have picture or diagram of the external oil piping for a ’33 836.

    I have a 2 outlet bypass valve coming out of the block. One goes to the oil filter and I guess the other “T”‘s into the outlet pipe from the oil filter to the block return?

    Thanks in advance



    I can send pictures of my ’33/836 piping.  I don’t however know if it is authentic.  I have cleaned the whole area and reinstalled the oil cooler, etc. exactly as it was when I got the car about a year ago. Those parts appear to be as original.  The car is relatively low millage at 50,000 miles.  Regards,  Don




    Thanks for the offer, I will take you you up on it.

    Sate safe and thanks again.




    oil bypass routing #1



    Ok, that gives me my answer. I don’t know that the parts are authentic, but I can follow the flow.

    Thanks for the help.



    Hi Bill,

    Attached is a photo of the correct full-flow oil circuit with horizontal filter on an original 836 (Larry Smothers’).



    PS: John Cislak makes the correct lines.


    Thank you Bob and Don,

    Here are the 2 relief valves I have.  The top is supposedly ’33 and the bottom is ’35 and has a small fitting out of the top right angle elbow.


    Based on the picture of Larry’s car. This valve is directly under the oil filter but has only one opening. The 2 I have have 2 outlets and a sliding cap and sleeve internally which I think bypasses the oil if there is too much pressure to the filter (clogged?)

    There are 2 part numbers and there appears to be a break at engine 235121.


    Hi Bill,

    The bypass valve (“oil relief valve”) has an internal spring and piston which opens if the OIL COOLER is clogged. (The oil flows first from the oil pump outlet under the water pump to the filter, then to the “T” where it goes to the cooler and the bypass valve simultaneously.)  I see no part number break in the 1933 parts book.  My ’33 sedan has the single outlet valve like Larry’s and is engine #235328. Here is a picture of the four types of relief valves known (courtesy of John Cislak).  Your two appear to be identical to each other (with slightly different fittings) and are the Seagraves 8-cyl type on the left (without the small oil gauge fitting shown in the pic.)  (1933 P-A 8-cyl oil gauge tube comes off at the back of the block, while the rest come off the valve body.)  If you want to be absolutely authentic, you need the one on the right.  Otherwise, just use the side connection on your two and plug the straight connection (or vice versa, whichever lines up or appeals visually).  If you block off the oil cooler like some of us, you can remove the spring and piston in the valve so the oil flows thru the valve a little quicker on startup.



    Thanks Bob,

    I guess I am looking for one of those on the right. Put an ad in the Emporium.

    Anyone need a later 8 valve. Probably ’34/35 on?


Viewing 10 posts - 1 through 10 (of 10 total)
  • You must be logged in to reply to this topic.