Hot Rods Cadillac 331 Oil lines

Can anyone direct me to an oil line diagram for a 55 Cadillac 331 motor?

Even some pictures of the passenger side of the block would help and how the oil lines run up to the heads.

I bought my motor in pieces and some of the plugs on the side of the block were removed and some had flared fittings in them. I bought a 331 manual but must have got a bootleg copy because it is not covered in the book I have. I know its a silly question but any help is appreciated.

 

Can you find an old Motor Manual for that time period?

 

I found on on CD that does not have much info in it

 

Post pictures of both sides and front of the block and I will explain them to you.

 

The plug fittings holes are circled in red., Thanks dude ,Any help is appreciated

 

Good pics.
First pic. Left - oil filter inlet, 1/8" pipe thread (pressure). Right - oil passage to rockers 1/8" pipe thread, need to be plugged. Behind the fan on the right side there is an opening in the block that is the return for the oil filter, 1/8" pipe thread.

Second pic. Left - vacuum fitting (goes to vac pump, attached to oil pump) Plug with 1/8" pipe plug. Right pic - water jacket, plug with 1/8" pipe plug.

Third pic. The two 1/4" pipe openings on the left are oil, one is used for the gauge, one is plugged.
Right side is oil for the rockers, should be plugged with an 1/8" pipe plug. Although something is odd, with the stud & nut, Maybe drilled out & plugged with stud ?

Fourth pic. Water jacket - 1/8" pipe plug.

I hope this helps.

 

Hell Yes!!! thanks you made my day!!

 

Nice. Amazing knowledge base, here on the HAMB

 

The blue thing is a hydraulic style cap I reckon capping off an SAE fitting,you guys refer to as an AN fitting I think. I don't know why it would be there though.
IMHO

 

I just had it in there as a plug while sorting things out

 

Quick question, I've seen multiple times the oil filter return line is referenced as being in the block near the timing cover. I have a 1955 331 and I don't see anything like that on it. However, my fuel pump stand has an 1/8 pipe thread in the top that I believe was where the oil filter return was located. Does this sound correct?

Also, does the oil filter feed line have a restriction in it like a flathead?

 

Yes and yes, incorporated in the brass 90 fitting in let inlet of your filter I believe.

 

From a motors manual The rear main gets oil first 1 and 3 main gets oil from the right lifter gallery 2 and 4 from the left . the cam journals from the corresponding mains the bypass filter from the front of the left lifter gallery

 

I checked and I don't have the original fittings. Do you know the restriction size so I can make my own? Thanks!

 

The steel line is only 3/16” OD and the orifice in the fitting is drilled 7/64”(.109”) as shown in one of the pics.
It’s almost like the line itself is acting like an orifice though as the ID of it would be about the same.

 

Thanks for that, so it's not as small as a flathead that's for sure. I'll dig around I may have a fitting like that after all.