Differences in the original oil pumps

[modela@aol.com]

Help! I have questions that can not be answered by the Judging Standards or Les Andrews Red Book in my preliminary research. Any pump experts out here?


I have 3 oil pumps that I am restoring and all of them are slightly different. The oil output opening is either a small round hole, an oval slot hole, and a big round hole. My questions are:
What are the years of the engines that they should match up to?
Is one better for supplying the maximum oil output or psi pressure?


Other differences are the cans are either soldered on, or held on by two slotted bolts. The soldered can version of the oil pump also has a idler gear that has a concave machined at the gear botttom and the other two pumps have square cut gears that are flat on both ends without the concave.

Out of these three pumps is there one that might be slightly better to use? Please inform me on these pumps. Thank you.
Dave

 

[emf]

I looks like the one on the left with the soldered can has already had the output opened for more flow. According to the Burtz guide, this one is not a good candidate for increased oil flow/pressure. The center one and the right hand one should be about the same for modifying.



Frank

 

[oldspert]

When I pulled the oil pan off of my engine number matching 29, the oil pump had the soldered on can. the solder had broken loose and the can was loose. I ordered a new pump. The new one had the slotted exit holes that were 1/8" by 1/4", so I opened both sides up to 1/4" diameter for more flow. The new one also had a slot machined like the third one in your pic. My car was built in Canada if that makes any difference.

 

[modela@aol.com]

A buddy also has a 1929 with the soldered can oil pump. Also was told that one is actually a Model B engine oil pump. Place your guesses now on which one…

 

[J Franklin]

The differences are most likely due to where the pump was made and what any rebuilder has done to it. Early pumps had a smaller bore.

 

[rotorwrench]

I've found several cracked cast iron bodies over time. I like the old forged ones. They don't crack.