Oil pump differences

[markb]

I am in the process of rebuilding some oil pumps.  Here’s a pic of six that I have.  The top row is from diecast engines and the bottom row is from sandcast engines.  The one on the lower right is from E100.  I didn’t see a thread about this so before I started taking them apart I carefully looked them over and made some interesting observations.  There are four different versions that I see.  I’ll call them early sandcast (E100), later sandcast (E1490 & E1789), early diecast and later diecast.


The early sandcast pump has “8” bolts on the oil stopper valve cap, the others do not.


Both early and later sandcast pumps (like the one on the left) have a rougher sandcast-like finish than the diecast versions, especially on the right and left end plates.


This view shows a plug that is on all pumps except the later diecast (shown on the right).


This picture shows a later diecast on the left, early diecast in the middle and a sandcast on the right.  Notice the lack of a plug in the upper right area of the later diecast pump and the cover is different.


There is a difference in the casting of the later diecast (on left).  All the others are like the pump on the right.


I saved the best for last.  The early sandcast pump (on the right) has a relief valve cap that is tapered down from the hex.  All others are just flat.  I definitely have to save that piece.

[greggo325]

Thanks for posting this Mark!  I can't wait to see what comes out of #371 

[kmb69]

Thanks Mark. Very interesting.

Keith

[kenhan]

Thanks! Looking forward for more!
I´m currently into restoring E1007384 and need to know differences like this.

Keep on!

/Ken

[markb]

I found another difference between sandcast pumps and diecast pumps.  All of the sandcast pumps have a number stamped on them.  They happen to be in order of age, in other words the bigger the number the newer the motor.  Maybe a coincidence.  The diecast pumps had no numbers.

[kp]

All very interesting stuff Mark, so much so I'm going to delve into my boxes of stuff and be surprised 

[markb]

Another difference.  The #136 pump out of E100 did not have any punch marks on the rotors. 

[Sgt.Pinback]

So are there differences from diecast to K1-K6?

Regarding pic no. 4

http://cb750sandcastonly.com/coppermine/albums/userpics/10002/CIMG3393.JPG

My oil pump has the cover of the early diecast but no plug as it should have.. Can you please identify that one ?

[markb]

Unfortunately I don't know the VIN's that the diecast pumps came from.  I'm pretty sure the earlier ones were from K0's.  The only thing I know for sure is that they didn't come from sandcast engines.  And I really don't know much about engines later than K0's.  Sorry I can't help.

[greggo325]

The pump from 371 has the 8 bolts, tapered plug, and the number stamped appears to be 719

[markb]

Here are some oil pumps posted by member dirfri#69.  Notice the stamped numbers.

Hallo, die frühen Öilpumpen waren alle mit Nummer.

[Steve Swan]

looking at all these pictures, appears the stamped numbers go higher as the Evin goes higher... ?  and every number seems like it is probably different.  i think this shoots my "inspector/batch theory" to hell.  looks like these oil pumps had a vin of their own.....

[markb]

Here's a chart of the engine numbers with their pump numbers from dirfri#69, greggo325 and me.
E53 - #84
E100 - #136
E371 - #719
E376 - #582
E1490 - #1880
E1789 - #2138
E2577 - #2578
They do tend to get bigger with the later engines but E371 and E376 are out of order.  I'm guessing the match up is like the engines to frames.  Kind of in order but random.